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Interpreting dragonfly diversity to aid in conservation assessment: Lessons from the Odonata assemblage at Middle Creek, north-eastern Victoria, Australia
Abstract
In order to evaluate single-occasion sampling in compiling inventories for Odonata, larvae were sampled on 20 occasions from 1987–1990 at a site on Middle Creek, north-eastern Victoria, and adults sought also on each visit to more fully evaluate the diversity of the asemblage, and limitations of depending on a single life stage for this purpose. A total of 18 species (7 Zygoptera, 11 Anisoptera) included 15 species collected as larvae and 16 as adults. Few species were common as larvae, and about half the 2806 specimens identified were Austrogomphus cornutus Watson. Orthetrum caledonicum (Brauer) and Ischnura heterosticta (Burmeister) were also abundant, and these three species were also the most common as adults. The number of species obtained ranged from 2–9 on different occasions, and represent different 'habitat groups' within the local fauna. The Middle Creek odonate fauna appears to be much richer than that of a nearby site on the Kiewa River (12 species), and reasons for this are discussed. Seasonal variation in species representation and relative abundances are noted. Any single sample occasion provided insufficient knowledge of the total assemblage to interpret odonate diversity reliably.
... There is value in knowing which adult male Odonata species are resident, to characterize a habitat in terms of the species that occur there in the highest numbers and breeding there regularly (Hawking & New 2002). Furthermore, resident adults would be more affected by changes in the immediate environment than would tourist species, and would therefore be of the greatest value as indicators. ...
... Monitoring abundant resident species may be important for detecting early decline of the habitat (Hawking & New 2002). However, monitoring rare species is also important as they can be indicative of relict or undisturbed conditions and used to rate the importance of any site within its biotope groups (Eyre et al. 1986). ...
... Furthermore, Hawking and New (2002) found that the diversity and abundance of larvae varies considerably, even on consecutive dates. This shortcoming is partly overcome by the SASS5 method which specifies the habitats to be sampled, so that there is no 'chance' 88 sampling of different substrates. ...
... For lentic-breeding adult odonate communities, there seems to be little if any justification for the temporal design of orderly surveys in applied research (Osborn & Samways, 1996;Rith-Najarian, 1998;Hawking & New, 2003;Hornung & Rice, 2003;D'Amico et al., 2004;Kadoya et al., 2004Kadoya et al., , 2008Bried & Ervin, 2005;Foote & Hornung, 2005;McCauley, 2006;Bried et al., 2007a;Butler & deMaynadier, 2008;Reece & McIntyre, 2009;Raebel et al., 2010;Samways & Sharratt, 2010). The general recommendations of Schmidt (1985) are often cited, but to our knowledge there have been no attempts to quantify diversity information biases at competing levels of temporal survey effort for odonates. ...
... Surveys spanned all of or a significant portion of the optimal recording period for teneral and reproductive adults in temperate zones (Schmidt, 1985). The sampling objective was to survey for 1 h at weekly intervals for at least 15 weeks (20 preferred), which exceeds the effort typically applied in formal adult odonate studies (Osborn & Samways, 1996;Rith-Najarian, 1998;Hawking & New, 2003;Hornung & Rice, 2003;Kadoya et al., 2004Kadoya et al., , 2008Bried & Ervin, 2005;Foote & Hornung, 2005;McCauley, 2006;Bried et al., 2007a;Butler & deMaynadier, 2008;Reece & McIntyre, 2009;Raebel et al., 2010;Samways & Sharratt, 2010). Most sites retained for analysis were surveyed on an approximate weekly basis (Table 1); exceptions were dealt with at the analytical stage (see Data analysis). ...
1. Repeat surveys are needed to capture a representative spectrum of adult odonate richness at a site, but specifics on frequency and duration of surveys and associated inferential biases are poorly understood.
2. Weekly 1 h surveys of mature male dragonflies and damselflies were repeated at least 15 times at 19 ponds, lakes and wetlands scattered throughout North America. For each site, we tallied the data remaining when the weekly frequency was reduced to 75% (every 1.5 weeks), 50% (biweekly), 33% (triweekly), and 25% (monthly) and the 1 h survey to 50, 40, 30, 20 and 10 min subsets.
3. Reducing the original effort by half (i.e. to 30 min biweekly) retained about 80% of the species on average. The smallest effort (10 min monthly) retained about 49% of species. The greatest rate of information loss occurred between 20 and 10 min.
4. Across‐site analysis found that data subsets correlated to the original data set ( r > 0.81) despite up to 50% species loss. Strong correlations ( r ≥ 0.98) remained with 10–15% species loss.
5. Biweekly surveys lasting 20–40 min each may provide a representative and cost‐effective sample of adult odonate richness in lentic study sites. Losing a handful of species should not greatly undermine richness and compositional comparisons among sites.
... SARIMAX allowed us to use past changes in male assemblage structure for forecasting future insect abundance. Ecological forecasting can be useful for the development of early warning systems interested in detecting population trends of threatened, endangered, keystone, or common species and detecting the early decline of habitat suitability 65,66 . Together, with other modeling techniques, previous studies have proven sensitive to environmental variables and are increasingly used by land managers to monitor ecosystem conditions 66,67 . ...
Forecasting insect responses to environmental variables at local and global spatial scales remains a crucial task in Ecology. However, predicting future responses requires long-term datasets, which are rarely available for insects, especially in the tropics. From 2002 to 2017, we recorded male ant incidence of 155 ant species at ten malaise traps on the 50-ha ForestGEO plot in Barro Colorado Island. In this Panamanian tropical rainforest, traps were deployed for two weeks during the wet and dry seasons. Short-term changes in the timing of male flying activity were pronounced, and compositionally distinct assemblages flew during the wet and dry seasons. Notably, the composition of these distinct flying assemblages oscillated in consistent 4-year cycles but did not change during the 16-year study period. Across time, a Seasonal Auto-Regressive Integrated Moving Average model explained 75% of long-term variability in male ant production (i.e., the summed incidence of male species across traps), which responded negatively to monthly maximum temperature, and positively to sea surface temperature, a surrogate for El Niño Southern Oscillation (ENSO) events. Establishing these relationships allowed us to forecast ant production until 2022 when year-long local climate variables were available. Consistent with the data, the forecast indicated no significant changes in long-term temporal trends of male ant production. However, simulations of different scenarios of climate variables found that strong ENSO events and maximum temperature impacted male ant production positively and negatively, respectively. Our results highlight the dependence of ant male production on both short- and long-term temperature changes, which is critical under current global warming.
... Yet, there are many risks associated with sampling endangered native species such as that they may derive from non-viable or sink populations [26]. On the other hand, monitoring the most abundant species of an ecosystem can be critical for the early detection of disturbance signs [27]. Despite the fact that non-indigenous species may generally lack high specificity of a unique system, by being the most abundant and wide-spread species within the assemblages they have high probabilities of being sampled and could provide information relating to their inhabiting area [28]. ...
Studies of plastic contamination in freshwater ecosystems and their biota remain scarce, despite the fact that the vast majority of plastic waste initially passes through lotic ecosystems. Biomonitoring provides valuable information regarding plastic pollution and microplastic threats to biota and human health. The aim of this study was to explore the potential use of a non-indigenous fish species as a bioindicator of microplastic pollution in an Eastern Mediterranean River. Our study area is located in a heavily modified and vastly impacted urban river which flows through the largest part of the Metropolitan area of Athens, Greece. We used an introduced chub species (Squalius vardarensis) to assess microplastic ingestion in the river. The results indicated moderate occurrence and abundance of microplastics in the fish gastrointestinal tracts; one-third of specimens (35%) contained microplastics, although the average number of microplastics per specimen was relatively low (1.7 ± 0.2). Overall, the abundance of microplastics in the water confirmed the moderate level of microplastics contamination in our study area. The major polymer types of microplastics identified by FT-IR analysis were: polyethylene (PE), polyvinyl alcohol (PVA) and polypropylene (PP); reflecting the fragmentation of larger litter from industrial packaging and/or household goods. Surface runoff of the urban environment, via motorways and major road networks, could be the contributing factor to the reported microplastics. Our results suggest that generalist's non-indigenous species such as chubs could be used as bioindicators of microplastics in inland waters. Introduced fishes can be a feasible, nondestructive, and cost-effective option for the assessment of microplastics in freshwater ecosystems, while freshwater chubs' high abundance and omnipresence in European rivers further serve this scope. However, it is worth noting that the suitability of any particular species as a bioindicator of microplastics may depend on a variety of factors, including their feeding behavior, habitat, and exposure to microplastics in their environment.
... Selain itu, penelitian yang dilakukan di beberapa kawasan di Malang Raya oleh (Albab, Leksono, & Yanuwiadi, 2019;Rahadi, Feriwibisono, Nugrahani, Dalia, & Makitan, 2013) untuk mengetahui keanekaragaman, komposisi, dan struktur komunitas odonata di ekosistem dataran tinggi dan dataran rendah pada perairan lotik dan lentik. Dengan demikian, perubahan kualitas lingkungan dapat diketahui dengan pemantauan berkala terhadap kelimpahan 394 Jurnal Pendidikan, Vol. 6, No. 3, Bln Maret, Thn 2021, Hal 393-397 capung lokal (Hawking & New, 2002). Berdasarkan hal tersebut, bioekologi capung dapat dikembangkan sebagai bahan ajar bagi mahasiswa Biologi dalam mempelajari materi struktur komunitas. ...
p> Abstract: This research has been conducted to develop a Bioecology e-book based on research of the dragonfly community structure around the springs in Malang Raya. The type of research is research and development.The research used ADDIE development model includes stagesof analyze, design, develop, implement, and evaluate. Research data collection used the validation sheet of material expert, the validation sheet of learning expert and the practicality sheet. Product trials were conducted in the Deaprtment of Biology, State University of Malang with 28 students. The results of evaluation by material expert validator showed that the e-book was quite valid (76%), results by learning expert validator was very valid (98,5%) and field trials by students that e-book was very practical and could be used with e few revisions (88%).
Abstrak: Penelitian ini telah dilakukan untuk mengembangkan e-book Bioekologi capung berbasis penelitian struktur komunitas capung di area sumber mata air Malang Raya. Jenis penelitian ini merupakan penelitian dan pengembangan. Penelitian ini menggunakan model pengembangan ADDIE dengan tahap menganalisis, merancang, mengembangkan, mengimplementasi dan mengevaluasi. Pengumpulan data menggunakan lembar validasi ahli materi, lembar validasi ahli pembelajaran, dan lembar kepraktisan. Uji coba produk dilakukan di jurusan Biologi FMIPA Universitas Negeri Malang dengan 28 mahasiswa. Hasil penilaian oleh validator ahli pembelajaran menunjukkan e-book dinyatakan valid (98,5%), penilaian oleh ahli materi cukup valid (76%) dan uji coba di lapangan oleh mahasiswa menyatakan e-book sangat praktisdan dapat digunakan dengan sedikit revisi (88%).
... Few data are available from which to infer a sampling frequency and sampling visit duration that will detect all or nearly all species that occupy even a small and limited habitat. Sites could be sampled as infrequently as once, which would be clearly insufficient to interpret odonate diversity at a site (e.g., Hawking and New 2003), to many dozens of times. As alluded to earlier, DuBois et al. (2020) were still finding new species after 36 visits over 18 years to a relatively small and simple pond, and Buchsbaum et al. (2016) had a similar result after 400 visits to a much larger and more complex suite of habitats. ...
Various logistical questions must be addressed when surveying or monitoring dragonflies and damselflies (Odonata) in Wisconsin. These include: 1) when, how often, and for how long the sampling should be done, 2) what sampling gears and how many observers should be used, 3) what habitats should be sampled, and 4) on what life stages a survey should focus. In this report I review and synthesize the relevant literature on Odonata sampling protocols to provide guidance for Odonata surveys in Wisconsin. Any survey design should be driven by the goals for the effort including the levels of accuracy and thoroughness the investigators are willing to accept; no single survey design will meet all possible goals. Obstacles to survey goals include complications with species identification, difficulties in detecting rare species, influences of season, weather, time of day, and habitat, limitations of sampling gear, issues related to sampling frequency and duration, and the peculiarities of various species. Surveys should primarily target adults, usually males, but nymphs and exuviae should be sought for some taxa, particularly if confirmation of reproduction at a site is needed. All aquatic habitats should be targeted in property surveys. The most effective way to increase the detection of rare species is to increase effort. Recommendations for survey timing and sampling frequency are provided.
... van Lexmond et al., 2015;Zeng et al., 2013). Dragonflies and damselflies (Odonata) are regarded as important indicators of the ecological quality of aquatic environments (Hawking and New, 2002;Kadoya et al., 2011;Steytler and Samways, 1995). Several investigations have reported the negative effects of pesticide application on Odonata communities. ...
The negative influence of agrochemicals (pesticides: insecticide, fungicide, and herbicide) on biodiversity is a major ecological concern. In recent decades, many insect species are reported to have rapidly declined worldwide, and pesticides, including neonicotinoids and fipronil, are suspected to be partially responsible. In Japan, application of systemic insecticides to nursery boxes in rice paddies is considered to have caused rapid declines in Sympetrum (Odonata: Libellulidae) and other dragonfly and damselfly populations since the 1990s. In addition to the direct lethal effects of pesticides, agrochemicals indirectly affect Odonata populations through reductions in macrophytes, which provide a habitat, and prey organisms. Due to technical restrictions, most previous studies first selected target chemicals and then analyzed their influence on focal organisms at various levels, from the laboratory to the field. However, in natural and agricultural environments, various chemicals co-occur and can act synergistically. Under such circumstances, targeted analyses might lead to spurious correlations between a target chemical and the abundance of organisms. To address such problems, in this study we adopted a novel technique, "Comprehensive Target Analysis with an Automated Identification and Quantification System (CTA-AIQS)" to detect wide range of agrochemicals in water environment. The relationships between a wide range of pesticides and lentic Odonata communities were surveyed in agricultural and non-agricultural areas in Saga Plain, Kyushu, Japan. We detected significant negative relationships between several insecticides, i.e., acephate, clothianidin, dinotefuran, flubendiamide, pymetrozine, and thiametoxam (marginal for benthic odonates) and the abundance of lentic Epiprocta and benthic Odonates. In contrast, the herbicides we detected were not significantly related to the abundance of aquatic macrophytes, suggesting a lower impact of herbicides on aquatic vegetation at the field level. These results highlight the need for further assessments of the influence of non-neonicotinoid insecticides on aquatic organisms.
... Monitoring abundant resident species in the studied wetlands, e.g., L. macrostigma in Psili Ammos, may be important for detecting the early decline of a habitat (Hawking & New 2002). Additionally, resident stenoecious species, e.g., E. fatime, Chalcolestes parvidens (Artobolevskij, 1929), and Cordulegaster sp. ...
Dragonflies (Odonata) are considered to be valuable indicators of hydroecosystems. This study reports the composition of the dragonfly assemblages in four wetlands of Samos Island, Greece, in a geographic area especially vulnerable to climate change where a trend towards a drier climate has been observed in the last decades. Dragonfly assemblages have not yet been studied on Samos. The analysis based on the number of different species and their autochthony revealed clear differences among the wetlands. The eutrophic Glyfada Lake, despite its variable hydrology resulting from drought-the seasonal decrease in water availability-harboured the largest diversity of dragonflies, larger than the oligotrophic Mesokampos Lake. The assemblage of the spring and rivulet at Mytilini, although also influenced by drought, had its own set of species of high autochthony. The seasonal brackish lake and marsh of Psili Ammos had the lowest number of species and was dominated by one very abundant breeding species. Drought was the main factor affecting the number and composition of species. The collected data create a reference for the future monitoring of trends in the composition of odonatofauna under the changing climate of Samos Island.
... Dragonflies are often used as bio-indicators of the status, stability and integrity of freshwater ecosystems. Because of the complex habitat requirements of the individual species, their presence and abundance indicate the wealth and favourable conservation status of the freshwater ecosystem they inhabit (Corbet 1999, Hawking & New 2002. Additionally, their conspicuousness and sensitivity to small-scale changes in environmental conditions make them extremely valuable for a rapid assessment of the freshwater ecosystem's quality (Moore 1997, Mortimer et al. 1998). ...
Data related to the 41 species of the dragonfly fauna of central and southwestern Republic of North Macedonia and nearby Albania, gathered during the post European Congress on Odonatology 2012 fieldtrip on July 6-13th, 2012 are presented. The Ohrid-Prespa region was particularly investigated. The majority of previous data available for this area is old and outdated. Additionally, recent degradation of habitats, combined with sporadic records of some patrimonial species made new surveys necessary. The presence of Gomphus schneiderii Selys, 1850 and S. flavomaculata in the region was confirmed whereas L. pectoralis was not found again. Conversely, Coenagrion scitulum (Rambur, 1842) was observed in Albania for the first time. The national Odonata checklists contain now 63 species in Republic of North Macedonia and 59 in Albania.
... First, we generated a morphological and life-history traits-by-species matrix from collected specimens to compute a principal component analysis (PCA) prior to the construction of the functional hierarchical classification. Second, the different components (axes) of the PCA were used as combinations of traits to define a Euclidean functional space with reduced uncorrelated dimensions, where each species is represented by its PCA axis scores (Hawking and New, 2002). This approach is an efficient way to produce high quality functional spaces where the weight of each synthetic trait is relevant to the fraction of the total trait variance it explains Maire et al., 2015). ...
Research has repeatedly shown that ongoing habitat loss and the increasing frequency of extreme climatic events have altered fundamental biological processes, threatening biodiversity and ecosystem functioning worldwide. However, the multitude of interacting factors underlying the impacts of these threats remain poorly understood in tropical forests. This is unfortunate because the majority of terrestrial biodiversity resides in these habitats. The responses of organisms to environmental changes are often studied indirectly, for example, using discrete snapshots at different time periods at the same location. This is due to the challenges of compiling long-term data, especially for invertebrates. Evaluating how functionally important species assemblages will respond to anthropogenic threats requires continuous long-term monitoring. This is vital for arthropods because they are responsible for crucial ecosystem services and human food security. Here, we review existing arthropod monitoring schemes and consider some innovative avenues for future research that promise to improve monitoring of this important group in tropical systems.
... The impacts of systemic pesticides, including neonicotinoids and fipronil, on biodiversity and ecosystems are a global concern (van der Sluijs et al. 2015;van Lexmond et al. 2015). Dragonflies (Odonata) are regarded as important indicators of aquatic environments (Steytler and Sanways 1995;Hawking and New 2002;Kadoya et al. 2011;Kasai et al. 2016;Baba et al. 2019). ...
The impacts of systemic pesticides on biodiversity are a major ecological concern. Rapid population declines of Sympetrum species (Odonata: Libellulidae) have been reported in various localities in Japan beginning in the 2000s. Several studies suggested that nursery box use of fipronil in paddy fields to prevent insect feeding on rice seedlings negatively impacts Sympetrum larvae. Although several other Odonata species are suspected to have declined significantly in recent decades, accurate evaluations of their population declines and identification of the causes are difficult due to limited data on population density prior to the declines. In addition, a recent study revealed that herbicide use negatively affects phytophilous species, but positively impacts benthic populations of lentic Odonata by reducing the prevalence of macrophytes. To evaluate the changes in the abundance of Odonata during recent decades, we conducted line transect observation of Odonata populations at one site along the Tafusegawa River in Saga Plain, northern Kyushu, Japan in 2000 and 2015–2016, before and after the use of fipronil in paddy fields in this area. We identified that Sympetrum eroticum eroticum (Selys) (Libellulidae) populations have significantly decreased in recent years. In addition, prevalence of a lotic benthic species, Asiagomphus pryeri (Selys) (Gomphidae), has significantly decreased in this time period. Other lotic benthic species have also declined in this area, suggesting that benthic environments might have degraded in recent years. In contrast to the decrease of the abovementioned species, prevalence of the lentic and benthic species Orthetrum melania melania (Selys) and Rhyothemis fuliginosa Selys (Libellulidae) (Libellulidae) significantly increased. The densities of lentic phytophilous species appear to have decreased, suggesting that reduction of macrophytes in surrounding lentic environments could be involved in these changes.
... Population trends of particular species are further affected by their respective ecological and life-history traits (Melero et al. 2016), with multivoltine insect species experiencing steeper population declines than uni-or bivoltine ones (Börschig et al. 2013). Also, moths and dragonflies are highly sensitive to changes in ecological parameters and environmental quality (Erhardt and Thomas 1991;Hawking and New 2002;Kadoya et al. 2004). Their declining abundance can thus be ascribed to multiple factors, including human-driven land-use change, agro-chemical pollution, and global warming (Wilcove et al. 1998;Conrad et al. 2006;Hahn et al. 2015;Sánchez-Bayo and Wyckhuys 2019). ...
Vast numbers of insects annually engage in trans-latitudinal migration and thereby impact structure and functioning of natural and man-made ecosystems. In eastern Asia, long-distance migration has historically been studied for single insect species rather than diverse species complexes. Here, we assessed migration dynamics of multiple economically important migratory species on an island in the Bohai Strait, China. Drawing upon 15-year trapping records of > 2.5 million specimens, we unveil inter- and intra-annual shifts in the species composition and abundance of migrant individuals. Migrants belonged to 9 orders and 36 families, primarily consisting of Lepidoptera (79% individuals), Odonata (8%), and Coleoptera (4%). Seven crop-feeding noctuids, e.g., Helicoverpa armigera (Hübner), Mythimna separata (Walker), represented 54% of the total trapping records. Trap catches exhibited marked seasonal variation, with the highest capture rate during early fall. Yearly abundance of migratory noctuids was coupled with that of their associated natural enemies. Although overall trap catches did not decrease over the monitoring period, the entire order of Odonata experienced a 14.1% annual rate of decline. Furthermore, 19 out of 108 species exhibited a progressively declining abundance over time, including the cosmopolitan cutworm Agrotis ipsilon (Hufnagel) and the insectivorous dragonfly Pantala flavescens Fabricius. Our work provides unprecedented insights into insect migration dynamics in eastern Asia, helps fine-tune forecasting and early-warning systems of crop pests, and thereby guides integrated pest management within local agro-landscapes. Also, a long-term tracking of migrant insect populations can shine light on the fate of (insect-mediated) ecosystem services and trophic dynamic processes at a macroscale.
... On the other hand, anthropogenic activities not only influence soil, yet also degrade the aquatic environment and significantly affect the existence of dragonfly species and community within that area (5). It is stated that regular monitoring on the abundance of local dragonflies can reveal the degradation of environmental quality (6), while the well-organized monitoring on rare dragonflies and damselflies can provide a reliable indicator on the habitat sustainability as well as become the significant factor in assessing the importance of that habitat (7 (11). The lack of research on Odonata in Sumatra has created some difficulties in species identification, as this process should be ideally assisted by the guidebooks made specifically for this island, instead of by ones purposed for other localities. ...
Odonata, which consists of true dragonflies and damselflies, is considerably understudied in Sumatra, especially in West Sumatra region. While the campus area of Andalas University in Limau Manis provides many suitable habitats for dragonflies and damselflies, the least has been done in learning these organisms. In this paper, we intend to conduct the inventory of Odonata in Limau Manis area by using photography approach (by taking decent pictures only, without sampling the animal). After spending 14 days of data collection which spanned from October 2017 until February 2018), we listed 27 Odonata species. Of which, 11 species belong to four families under suborder Zygoptera and 16 species grouped into four families under suborder Anisoptera. Libellulidae is a family under Anisoptera that was found with most species members. Photography approach promises an immense help in doing species inventory for this animal group for its reliability in determining species identification without harming species’ population.
Keywords: damselflies, dragonflies, Libellulidae, Limau Manis area, photography approach
... On the other hand, anthropogenic activities not only influence soil, yet also degrade the aquatic environment and significantly affect the existence of dragonfly species and community within that area (5). It is stated that regular monitoring on the abundance of local dragonflies can reveal the degradation of environmental quality (6), while the well-organized monitoring on rare dragonflies and damselflies can provide a reliable indicator on the habitat sustainability as well as become the significant factor in assessing the importance of that habitat (7 (11). The lack of research on Odonata in Sumatra has created some difficulties in species identification, as this process should be ideally assisted by the guidebooks made specifically for this island, instead of by ones purposed for other localities. ...
Odonata, which consists of true dragonflies and damselflies, is considerably understudied in Sumatra, especially in West Sumatra region. While the campus area of Andalas University in Limau Manis provides many suitable habitats for dragonflies and damselflies, the least has been done in learning these organisms. In this paper, we intend to conduct the inventory of Odonata in Limau Manis area by using photography approach (by taking decent pictures only, without sampling the animal). After spending 14 days of data collection which spanned from October 2017 until February 2018), we listed 27 Odonata species. Of which, 11 species belong to four families under suborder Zygoptera and 16 species grouped into four families under suborder Anisoptera. Libellulidae is a family under Anisoptera that was found with most species members. Photography approach promises an immense help in doing species inventory for this animal group for its reliability in determining species identification without harming species’ population.
... Dragonflies have been repeatedly suggested as flagship species for ponds or other aquatic habitats (Hawking and New 2002;Clausnitzer et al. 2012). Compared to other surrogate species concepts, flagship species do not necessarily need to be ecologically significant but should be charismatic and conspicuous animals that engage the public (Caro and O'Doherty 1999;Verissimo et al. 2011). ...
Ponds are home to a diverse community of specialized plants and animals and are hence of great conservation concern. Through land-use changes, ponds have been disappearing rapidly and remaining ponds are often threatened by contamination and eutrophication, with negative consequences for pond-dependent taxa like amphibians or dragonflies (Odonata: Anisoptera and Zygoptera). Increasingly, restoration measures such as removal of shading terrestrial vegetation or submerged organic matter are implemented to counteract current threats, but how these measures affect the target taxa is rarely assessed. We tested if and how simple pond restoration measures affectionate diversity. We propose that pond restoration influences the light regime, which promotes aquatic and riparian vegetation important for different dragonfly life stages, thus increasing their diversity. Additionally, we assume that this changes dragonfly species composition between restored and unrestored ponds. We surveyed exuviae in the riparian and aquatic vegetation along the shore of 29 (12 restored, 17 unrestored) man-made ponds in southwest Germany and assessed environmental variables known to affect dragonfly diversity. We identified the cover of tall sedges and submerged macrophytes as the driving biotic variables for dragonfly diversity and species composition, with restoration measures affecting submerged macrophyte cover directly but tall sedges indirectly via available sunlight. This study demonstrates that simple restoration measures not only have a positive effect on overall dragonfly diversity, but also increase habitat suitability for several species that would otherwise be absent. We therefore propose dragonflies as a suitable flagship group for pond conservation. © 2018 Springer Science+Business Media B.V., part of Springer Nature
... Yoccoz et al., 2001) and forecasting future change in community structure and ecosystem function (Dornelas et al., 2014). Monitoring abundant resident (common) species may be crucial for detecting the early decline of habitats (Hawking & New, 2002). ...
In tropical rainforests, most assassin bugs (Hemiptera: Reduviidae) represent important predators preying on other arthropods. Apart from the hematophagous Triatominae of medical importance, Reduviidae remain poorly known.
Here, we address the importance of Reduviidae for long‐term monitoring of secondary consumers in tropical rainforests, using data from Barro Colorado Island ( BCI ), Panama. First, we demonstrate that light traps allow catching a wide and representative diversity of Reduviidae, and are more efficient than other collection methods tested.
Second, we present one of the very first checklists of Reduviidae for a tropical locality, including 118 species. These baseline data will be necessary for interpreting any long‐term changes in reduviid populations on BCI .
Last, we show that the low abundance of Reduviidae collected at light remains challenging for statistical analyses of long‐term population trends. During a 7‐year period (2009–2015), we observed no significant changes in the short‐term population dynamics of most reduviid taxa, although these results do not account for the complexity of the intra‐annual population dynamics of each species. In particular, the population of the rather abundant Panstrongylus geniculatus , which is a known vector of Chagas’ disease, appears to be fluctuating but so far is stable.
Daily maximum temperature and rainfall were negatively correlated with the overall abundance of Reduviidae during light traps surveys. During the past 25 years, global warming has induced significant increases in annual temperature and rainfall in Panama. Therefore, we conclude that reduviid populations on BCI may be vulnerable in the future to these global effects.
... Thus, many aquatic organisms in paddy fields need to escape the temporary dry conditions. Dragonflies (Odonata) have been regarded as an indicator of the ecological quality of aquatic environments [4][5][6][7] . In environments with no large fishes, both the adults and nymphs of dragonflies occupy a relatively high trophic level 8 , and thus cause top-down effects on paddy biological communities. ...
Several reports suggested that rice seedling nursery-box application of some systemic insecticides (neonicotinoids and fipronil) is the cause of the decline in dragonfly species noted since the 1990s in Japan. We conducted paddy mesocosm experiments to investigate the effect of the systemic insecticides clothianidin, fipronil and chlorantraniliprole on rice paddy field biological communities. Concentrations of all insecticides in the paddy water were reduced to the limit of detection within 3 months after application. However, residuals of these insecticides in the paddy soil were detected throughout the experimental period. Plankton species were affected by clothianidin and chlorantraniliprole right after the applications, but they recovered after the concentrations decreased. On the other hand, the effects of fipronil treatment, especially on Odonata, were larger than those of any other treatment. The number of adult dragonflies completing eclosion was severely decreased in the fipronil treatment. These results suggest that the accumulation of these insecticides in paddy soil reduces biodiversity by eliminating dragonfly nymphs, which occupy a high trophic level in paddy fields.
... This is highlighted by the presence of distinct or increased numbers of certain food items in the diet of M. ikei in different seasons. Examples of this include Mus musculus, which were only collected in winter samples when they are expected to be at their highest abundance following their peak breeding period in late summer and autumn (Saunders & Giles 1977), and an increase in the presence of aquatic insect larvae such as Hemicordulia spp. in summer as would be expected (Hawking & New 2002). ...
The diet of the endangered eastern freshwater cod Maccullochella ikei Rowland, 1985 was studied over 2 consecutive years in the Mann and Nymboida River system, Australia, to determine summer and winter feeding habits. Food items were extracted using non-destructive gastric lavage. In total, 268 M. ikei were gut-flushed over the 2 yr of the study; 191 contained at least 1 food item. A large variety and broad size range of items were recovered, from small aquatic insects to relatively large terrestrial animals. We found significant differences between the food items consumed by M. ikei in summer and winter. Seasonal differences related to the increased occurrence of crustaceans, small fish and terrestrial animals in the diet of M. ikei during winter, and more aquatic insects and molluscs in summer. Food items differed significantly among size classes, with larger M. ikei consuming fewer crustaceans and more large fish and terrestrial animals. Our study revealed that M. ikei displays high plasticity in seasonal dietary habits, changes diet and foraging tactics as it grows, and appears to not always consume what would be considered optimal forage. While many of the issues surrounding the conservation of M. ikei initially appear to be localised, aspects of its biology including its dietary habits also have context across broader scales.
... Odonata are sensitive and reliable indicators of environmental disturbance to forests and a variety of aquatic habitats (e.g. Chovanec et al. 2004;Stewart & Samways 1998;Hawking & New 2002;Lee Foote & Hornung 2005;Osborn 2005). For example, Stewart and Samways (1998) considered that a higher proportion of Anisoptera to Zygoptera species is an indication of a disturbed river. ...
Hydrophylita neusae n. sp. is described and illustrated. Hydrophylita is a small genus of Trichogrammatidae which now includes four species, all known to attack eggs of damselflies (Odonata: Zygoptera). A key to species is included and those known from the Neotropics are illustrated.
... They have significant potential as bio-indicators as their conspicuousness and sensitivity to small-scale changes in environmental conditions (MOORE, 1997;MORTIMER et al., 1998) makes them invaluable for a rapid quality assessment of freshwater ecosystems. The number of dragonflies can provide a quick indication of the health or richness of freshwater ecosystems (HAWKING & NEW, 2002). To maintain high species richness, it is essential to maintain a variety of biotopes (SUH & SAMWAYS, 2005). ...
... Freshwater habitats are severely threatened by multiple factors, including resource extraction, introduction of alien species, pollution, changes in land use, anthropisa-tion, urbanisation, and climate change (Clausnitzer et al., 2009;McGeoch et al., 2011;Simaika et al., 2013). Consequently, researchers have increased their efforts to evaluate the conservation status of invertebrate taxa (Hawking & New, 2002), mollusks (R egnier et al., 2009), and water beetles (Abell an et al., 2005). Odonates (dragonflies and damselflies) are ecologically important insects in freshwater habitats. ...
1. We assessed the conservation status of the three Mexican Paraphlebia damselflies based on the criterion B of the Red List of the International Union for Conservation of Nature’s (IUCN): P. hyalina, P. quinta, and P. zoe. According to this List, P. hyalina has not been evaluated, P. quinta appears as least concern, and P. zoe appears as Vulnerable. Geographical records were taken from literature, enquiries to specialists and field visits. We also projected the future potential geographical range area.
2. We generated species distribution models (SDM) for P. quinta and P. zoe (as there were not enough records for P. hyalina) as a surrogate of the extension of occurrence (EOO) and also calculated the area of occupancy. Future distributions were projected for years 2020, 2050, and, 2080 based on predicted
changes in climatic conditions.
3. Species distribution models predicted current EOO areas for P. quinta and P. zoe as 18 860 and 16 440 km2, respectively, and around 50% of their distribution coincides with agricultural, pasture or urban sites.
4. Our SDM results indicate that IUCN-based conservation status of the three species should be changed as follows: P. quinta and P. zoe moved to endangered category, and P. hyalina to data-deficient category based on the reduced EOO areas and the historical loss of habitat.
5. For P. quinta, future climatic projections suggest an initial reduction (2020) followed by an expansion (2050 and 2080) in suitable areas, whereas for P. zoe there will be a decrease in predicted area for the three time periods. Preserving areas that provide shade, high humidity and perching sites seems to be
a key for Paraphlebia species survival.
... Freshwater habitats are severely threatened by multiple factors, including resource extraction, introduction of alien species, pollution, changes in land use, anthropisa-tion, urbanisation, and climate change (Clausnitzer et al., 2009;McGeoch et al., 2011;Simaika et al., 2013). Consequently, researchers have increased their efforts to evaluate the conservation status of invertebrate taxa (Hawking & New, 2002), mollusks (R egnier et al., 2009), and water beetles (Abell an et al., 2005). Odonates (dragonflies and damselflies) are ecologically important insects in freshwater habitats. ...
We assessed the conservation status of the three Mexican Paraphlebia damselflies based on the criterion B of the Red List of the International Union for Conservation of Nature's ( IUCN ): P. hyalina , P. quinta, and P. zoe . According to this List, P. hyalina has not been evaluated, P. quinta appears as least concern, and P. zoe appears as Vulnerable. Geographical records were taken from literature, enquiries to specialists and field visits. We also projected the future potential geographical range area.
We generated species distribution models ( SDM ) for P. quinta and P. zoe (as there were not enough records for P. hyalina ) as a surrogate of the extension of occurrence ( EOO ) and also calculated the area of occupancy. Future distributions were projected for years 2020, 2050, and, 2080 based on predicted changes in climatic conditions.
Species distribution models predicted current EOO areas for P. quinta and P. zoe as 18 860 and 16 440 km ² , respectively, and around 50% of their distribution coincides with agricultural, pasture or urban sites.
Our SDM results indicate that IUCN ‐based conservation status of the three species should be changed as follows: P. quinta and P. zoe moved to endangered category, and P. hyalina to data‐deficient category based on the reduced EOO areas and the historical loss of habitat.
For P. quinta , future climatic projections suggest an initial reduction (2020) followed by an expansion (2050 and 2080) in suitable areas, whereas for P. zoe there will be a decrease in predicted area for the three time periods. Preserving areas that provide shade, high humidity and perching sites seems to be a key for Paraphlebia species survival.
... Uno de los aspectos ecológicos más trabajados ha sido el de su potencial como bioindicadores, analizando la tolerancia de algunas especies a factores fisicoquímicos (Ferreras-Romero, 1988;Carchini & Rota, 1985;Rodríguez, 2003, Remsburg et al., 2008, acumulación de metales en larvas de algunas especies (Gupta, 1995); efecto del aumento en la temperatura del agua provocado por reactores nucleares (Gentry et al., 1975;Thorp & Diggins, 1982), efecto provocado por descargas directas de drenaje a ríos , efecto por contaminación de pesticidas (Takamura et al., 1991;Hurtado-González et al., 2001), impacto provocado por el pastoreo bovino sobre las asociaciones de odonatos adultos (Hornung & Rice, 2003;Lee Foote & Rice, 2005), relación de los ensamblajes con las características del hábitat (Castella, 1987;Bulánková, 1997), uso de las larvas como indicadores de calidad del agua (Trevino, 1997), indicadores de riqueza total (Sahlén & Ekestubbe, 2001), indicadores de calidad riparia (Smith et al., 2007), estudios recientes han sido realizados con un enfoque de diversidad y conservación (Hawking & New, 2002;Clausnitzer, 2002;Bried et al., 2007). ...
... Assim, uma espécie que tenha ocorrido somente em duas das três veredas não-queimadas apresentará a métrica de fidelidade já reduzida em um terço e, de acordo com o método de A B C IndVal, não seria uma espécie indicadora, ainda que ocorra apenas em um dos tratamentos. Adicionalmente, o número de dias de amostragem em cada vereda deve ser aumentado para que seja possível a eliminação de registros casuais de espécies de Odonata devido à visitação temporária de corpos de água (Schmidt 1985, Hawking & New 2002. ...
As veredas são fisionomias abertas do bioma Cerrado, que desempenham papel essencial na proteção de nascentes. Por outro lado, as veredas também são consideradas de grande importância para uso direto das populações rurais que habitam o Cerrado brasileiro. Estes conflitos de utilização das veredas são hoje um grande desafio para a conservação da biodiversidade. Neste estudo objetivou-se testar o efeito do fogo sobre a riqueza e composição de Odonatas (libélulas) em veredas queimadas e não-queimadas na Estação Ecológica Serra Geral do Tocantins (EESGT). A riqueza foi estimada para cada uma das veredas amostradas através do método não-paramétrico Jackknife de primeira ordem. A análise de espécies indicadoras foi feita pelo IndVal. A similaridade na composição da comunidade de Odonata foi obtida através do índice de Chao. No total foram amostradas 33 espécies de Odonata, distribuídas entre cinco famílias. Nenhuma das espécies de Odonata esteve associada especificamente a ambientes queimados ou não queimados. As veredas queimadas apresentaram uma maior similaridade na composição das comunidades de Odonata do que as veredas não queimadas e o mesmo padrão pode ser observado quando considerada apenas a subordem Zygoptera. Este trabalho com comunidades de Odonata demonstrou que há impacto do fogo sobre a composição de espécies da subordem Zygoptera que possui menor capacidade de dispersão. Isso reforça a idéia de que o fogo é conhecidamente uma das principais ameaças sobre as áreas protegidas do Cerrado e uma ameaça à manutenção da biodiversidade de veredas da EESGT. Caso decisões de uso e manejo do fogo sejam tomadas, que estas sejam, imprescindivelmente, acompanhadas de pesquisas de monitoramento de veredas na EESGT.Â
... They have significant potential as bio-indicators as their conspicuousness and sensitivity to small-scale changes in environmental conditions (MOORE, 1997;MORTIMER et al., 1998) makes them invaluable for a rapid quality assessment of freshwater ecosystems. The number of dragonflies can provide a quick indication of the health or richness of freshwater ecosystems (HAWKING & NEW, 2002). To maintain high species richness, it is essential to maintain a variety of biotopes (SUH & SAMWAYS, 2005). ...
This study presents the results of dragonfly fauna research in the Turopolje region of Croatia. Faunal analyses were conducted in the period from 1986–2009, with some interruptions, while an ecological analysis (composition of dragonflies according to habitat characteristics such as vegetation structure, air temperature, cloudiness) was conducted in the period 2007–2009. Faunal and ecological analyses were carried out at seventeen and nine localities, respectively. A total of 35 dragonfly spe-cies was recorded, indicating high species richness in comparison to the total number of 67 species known in Croatia. Zoogeographic analysis of the recorded dragonfly species showed the domination of the Holo-Mediterranean element which indicates complex glaciation and interglaciation processes during the geological past in Europe, when the Croatian territory served as a refugium. The results show that the distribution and abundance of dragonflies are indicative of habitat characteristics (veg-etal structure, cloudiness and air temperature). Dragonflies prefer mosaic habitats (diverse vegetation structure) with average air temperatures ranging from 26–28°C and sunny weather. Since this re-search was conducted in only a part of the whole Turopolje region, and only adult specimens were sampled, further research should be focused on the life cycles of dragonflies and their distribution throughout the entire Turopolje region.
... Because of the habitat richness and good conservation state of the forests, meadows, rivers and streams, this area should be preserved in its natural state, and the stability, health and integrity of freshwater ecosystems can conveniently be indicated by dragonfly populations. Due to their sensitivity to human disturbances such as forestry and farming and due to the species' complex habitat requirements, their presence and abundance can indicate the value and conservation status of the sites they inhabit (Corbet, 1999;Franković, 1999;Hawking & New, 2002;Sàhlen, 2005;Bogdanović et al., 2008;Koch et al., 2013). Their conspicuousness and sensitivity to small-scale environmental changes makes them valuable for the rapid assessment of freshwater ecosystem quality (Moore, 1997;Mortimer et al., 1998) and thus they have been widely used to monitor habitat and water quality as well as the extent of the recovery of restored habitats (Clausnitzer, 2003;Suhling et al., 2006;Simaika & Samways, 2008). ...
45 original scientific paper / izvorni znanstveni rad In all, 32 dragonfly species were recorded between August 2010 and September 2011 at 21 localities in the Banovina region of Croatia, almost half of the total number known in Croatia. The most abundant species was Platycnemis pennipes while the rarest was Coenagrion ornatum. Ten of the recorded species are at a certain level of conservation concern and thus it is important to protect their habitats in region. U razdoblju između kolovoza 2010. i rujna 2011. godine na 21 postaji na području Banovine utvrđe-ne su 32 vrste vretenaca, gotovo polovina broja vrsta prisutnih u Hrvatskoj. Najčešća zabilježena vrsta je Platycnemis pennipes dok je najrjeđa Coenagrion ornatum. Među zabilježenim vrstama vretenaca, deset ih je pod određenim stupnjem zaštite zbog čega se ističe važnost očuvanja i zaštite njihovih staništa na području Banovine.
... They have significant potential as bio-indicators as their conspicuousness and sensitivity to small-scale changes in environmental conditions (MOORE, 1997;MORTIMER et al., 1998) makes them invaluable for a rapid quality assessment of freshwater ecosystems. The number of dragonflies can provide a quick indication of the health or richness of freshwater ecosystems (HAWKING & NEW, 2002). To maintain high species richness, it is essential to maintain a variety of biotopes (SUH & SAMWAYS, 2005). ...
This study presents the results of dragonfly fauna research in the Turopolje region of Croatia. Faunal analyses were conducted in the period from 1986–2009, with some interruptions, while an ecological analysis (composition of dragonflies according to habitat characteristics such as vegetation structure, air temperature, cloudiness) was conducted in the period 2007–2009. Faunal and ecological analyses were carried out at seventeen and nine localities, respectively. A total of 35 dragonfly spe-cies was recorded, indicating high species richness in comparison to the total number of 67 species known in Croatia. Zoogeographic analysis of the recorded dragonfly species showed the domination of the Holo-Mediterranean element which indicates complex glaciation and interglaciation processes during the geological past in Europe, when the Croatian territory served as a refugium. The results show that the distribution and abundance of dragonflies are indicative of habitat characteristics (veg-etal structure, cloudiness and air temperature). Dragonflies prefer mosaic habitats (diverse vegetation structure) with average air temperatures ranging from 26–28°C and sunny weather. Since this re-search was conducted in only a part of the whole Turopolje region, and only adult specimens were sampled, further research should be focused on the life cycles of dragonflies and their distribution throughout the entire Turopolje region.
... Odonates have become a valuable instrument for assessing aquatic systems (Girgin et al., 2010;Chovanec et al., 2014), habitat quality (Chovanec and Waringer, 2001;Harabis and Dolny, 2012), vegetation modifications (Foote and Rice, 2005) or influence of river structural characteristics in the species distribution (Smith et al., 2007;Jones, 2013) essentially because of (i) taxonomically well known; (ii) easily recognized; (iii) occupying a spectrum of habitats; and (iv) sensitive to alterations in water quality and ecological conditions of their habitats. Monitoring abundant resident species may be significant in the early habitat decline's assessment (Hawking and New, 2002), whereas rare species can be found out to characterize undisturbed conditions (Eyre et al., 1986). ...
Monitoring changes of anthropogenic impacts from a broad scope of species in biodiversity research require practical, easy‐to‐use and efficient assessment as well as monitoring methods. Odonates (Insecta: Odonata) are a valuable tool for assessing freshwater systems' quality and have been used as bioindicators of environmental variety.
The Águeda watershed, located in the central west of the Iberian Peninsula, shows an exponential increase in the last 60 years of natural resource exploitation coupled with alterations in consumer habits, causing significant environmental changes and deferred direct effects on the natural habitats.
Fourteen river sites, selected a priori , were sampled. Adult odonates were collected using standardized methods. Selected environmental variables and water quality parameters were evaluated in situ . Precipitation and altitude were the most important physical, environmental variables in explaining the assemblage structure. Meaningful abiotic–biotic as well as biotic–biotic relationships were set up. Furthermore, situations in the urbanized watershed area showed to be highly impacted and closely related with damselfly Ischnura graellsii , which should be targeted as a possible vulnerability indicator for polluted fresh waters.
A probability map for Ischnura graellsii distribution was performed using indicator kriging with external drift and spatial uncertainty obtain through the calculation of two categorical maps (binary), corresponding to the mean (0.485) and the trimmed mean by discharging the 10% lower distribution tail (0.533). The subsequent overlapping of both categorical maps (binary) allowed the definition of the higher spatial uncertainty map for surface water contamination. Copyright © 2014 John Wiley & Sons, Ltd.
... Species could be absent or uncommon at sites that are predicted to be environmentally suitable due to dispersal constraints, biotic interactions, unsuitable micro-habitats and stochastic effects (Heikkinen et al., 2006) or human habitat modification (Mangiacotti et al., 2013). For example, SDMs predicted 26 species could occur at Middle Creek in Victoria where Hawking and New (2002) sampled odonates (larvae and adults) intensively on 20 visits over three years. They found fine-scale patterns in sediment composition affected species composition, allowing 18 species to occur in the creek, four more in the nearby river and at least nine more in the surrounding area (Hawking & New, 1999), including all those species predicted by the models. ...
Aim
Invertebrates are often overlooked in assessments of climate change impacts. Odonata (dragonflies and damselflies) are a significant component of freshwater macroinvertebrate diversity and are likely to be highly responsive to a changing climate. We investigate whether climate change could lead to significant alteration of continental patterns of diversity and whether vulnerable species are taxonomically clustered.
Location
Australia.
Methods
Habitat suitability of 270 odonate species was modelled, and a simplified phylogeny was developed based on taxonomic relationships and expert opinion. These maps were then combined to compare species richness, endemism, taxonomic diversity ( TD ) and taxonomic endemism ( TE ) under climate change scenarios, and estimate turnover in species composition. Based on the concentration of vulnerable species in regions associated with Gondwanan relicts, we tested the possibility that a focus on species loss would underestimate loss of evolutionary diversity.
Results
Species richness of Australian Odonata is concentrated in the Wet Tropics, central‐north Australia and south‐east Queensland. Several additional regions support endemic assemblages, including the Victorian alpine region, the Pilbara and far south‐western Australia. Major shifts in composition are expected across most of the east coast in response to climate change, and Tasmania has the potential to become a major refuge for mainland species. For many regions, the loss of TD is greater than expected based on the changes in species richness, and the loss of suitable habitat was unevenly distributed among families. However, the potential loss of evolutionary diversity among vulnerable species was not significantly different from random.
Main conclusions
The major shifts in the distribution of Australian odonate diversity predicted to occur under climate change imply major challenges for conservation of freshwater biodiversity overall. Although major evolutionary losses may be avoided, climate change is still a serious threat to Australia's Odonata and poses an even greater threat to Australian freshwater biodiversity as a whole.
... Amongst freshwater invertebrates, the dragonflies (Order: Odonata) receive the same 'flagship' recognition that butterflies offer for terrestrial ecosystems (Hawking & New, 2002;Fleishman & Murphy, 2009). In comparison with other freshwater invertebrates, dragonflies have a long history of research that provides a solid basis for understanding the implications of climate change (Corbet, 1999;Có rdoba-Aguilar, 2008;Hassall & Thompson, 2008). ...
Freshwater ecosystems are highly vulnerable to the effects of climate change. Where long-term datasets are available, shifts in species phenology, species distributions and community structure consistent with a climate change signal have already been observed. Identifying trends across the wider landscape, to guide management in response to this threat, is limited by the resolution of sampling. Standard biomonitoring of macroinvertebrates for water-quality purposes is currently not well suited to the detection of climate change effects, and there are risks that substantial changes will occur before a management response can be made. This study investigated whether dragonflies, frequently recommended as general indicators of ecological health, are also suitable as indicators of climate change.
Data were analysed from standard bio-assessment monitoring at over 850 sites spanning a 9° latitudinal gradient in eastern Australia.
Using variation partitioning, we analysed the proportion of assemblage turnover in dragonflies and other macroinvertebrate assemblages that can be explained by climate and other environmental drivers. We also tested whether the utility of dragonflies as indicators improved at higher taxonomic resolution and whether the turnover of dragonfly assemblages was congruent with that of other groups.
Climate explained three times as much variation in turnover of dragonfly species than dragonfly and other macroinvertebrate assemblages at family level. The dissimilarity of dragonflies and varying turnover in each macroinvertebrate assemblage meant surrogacy amongst groups were low.
On the basis of the influence of climate on turnover of macroinvertebrate assemblages, dragonfly species distribution appears highly sensitive to climatic factors, making this taxon a potential useful indicator of climate change responses. However, the low surrogacy amongst assemblages also suggests that a shift in the focus of conservation management from specific taxa to the functional composition of assemblages across a diverse range of habitats is needed.
... Las comunidades bióticas tanto de ecosistemas terrestres como acuáticos, son muy sensibles a las alteraciones del medio, sean éstas de origen natural o antrópico. En ecosistemas acuáticos; la cantidad de materia orgánica, el estado trófico del agua, la productividad, la sedimentación, el uso de fertilizantes y la contaminación química, entre otros procesos, determinan la composición, abundancia y diversidad de las comunidades acuáticas asociadas (Hawking & New 2002). La alteración de cualquiera de estos procesos, produce cambios en las características físicas y químicas del agua, y en consecuencia, cambios drásticos en las características ecológicas de las mismas. ...
Population structure of Polythore gigantea (Odonata: Polythoridae) in lotic systems with differ-ent conservation states in Antioquia-Colombia. The knowledge about population structure and dynamics of some neotropical species, especially those living in lotic systems is still barely studied. This study had the aim to assess if the conservation status of some lotic systems, is related to some demographic variables of P. gigantea, so this may be used as a model for ecological monitoring. For this, we evaluated the population structure of P. gigantea three times per month (almost one sampling event every eight days) in four streams of the state of Antioquia, Colombia, from March-June 2009. The specimens were collected using entomological nets along a transect of 200m in the littoral zone of each stream. The insects were marked on the wings and the population size was estimated with the mark-recapture method. Our results showed that the largest population size was recorded for the stream "La Catedral" with aprox 299 individuals, followed by the stream "La Doctora" with 218 individuals. Nevertheless, no significant differences in population size among the evaluated streams were found; and no statistical relationships were found between vegetation variables and the population size of P. gigantea. However, taking into account the limited dispersal capacity of P. gigantea, its survival in the studied streams was considered to be at risk, due to the continuous modification of large riparian forest areas, which cause the increase of forest patches, with different levels of interconnection, and hinder long-term permanence of populations. Rev. Biol. Trop. 60 (3): 1205-1216. Epub 2012 September 01. Las comunidades bióticas tanto de eco-sistemas terrestres como acuáticos, son muy sensibles a las alteraciones del medio, sean éstas de origen natural o antrópico. En eco-sistemas acuáticos; la cantidad de materia orgánica, el estado trófico del agua, la pro-ductividad, la sedimentación, el uso de fer-tilizantes y la contaminación química, entre otros procesos, determinan la composición, abundancia y diversidad de las comunidades acuáticas asociadas (Hawking & New 2002). La alteración de cualquiera de estos procesos, produce cambios en las características físicas y químicas del agua, y en consecuencia, cambios drásticos en las características ecológicas de las mismas. En ecosistemas acuáticos, lóticos en particular, la deforestación, la destrucción del hábitat y el grado de intervención sobre las comunidades vegetales ribereñas, alteran las condiciones microclimáticas específicas de los cuerpos de agua, y por lo tanto, conllevan también, cambios en la composición, abundan-cia relativa y diversidad de las especies de este tipo de comunidades. Esta alteración y grado de intervención de la vegetación ribereña en eco-sistemas acuáticos lóticos, pueden tener efectos posteriores drásticos sobre todo el ecosistema (Thorp & Covich 2001).
... Amongst freshwater invertebrates, the dragonflies (Order: Odonata) receive the same 'flagship' recognition that butterflies offer for terrestrial ecosystems (Hawking & New, 2002;Fleishman & Murphy, 2009). In comparison with other freshwater invertebrates, dragonflies have a long history of research that provides a solid basis for understanding the implications of climate change (Corbet, 1999;Có rdoba-Aguilar, 2008;Hassall & Thompson, 2008). ...
Aim Freshwater ecosystems are highly vulnerable to the effects of climate
change. Where long-term datasets are available, shifts in species phenology,
species distributions and community structure consistent with a climate change
signal have already been observed. Identifying trends across the wider
landscape, to guide management in response to this threat, is limited by the
resolution of sampling. Standard biomonitoring of macroinvertebrates for
water-quality purposes is currently not well suited to the detection of climate
change effects, and there are risks that substantial changes will occur before a
management response can be made. This study investigated whether dragonflies,
frequently recommended as general indicators of ecological health, are
also suitable as indicators of climate change.
Location Data were analysed from standard bio-assessment monitoring at over
850 sites spanning a 9° latitudinal gradient in eastern Australia.
Methods Using variation partitioning, we analysed the proportion of
assemblage turnover in dragonflies and other macroinvertebrate assemblages
that can be explained by climate and other environmental drivers. We also
tested whether the utility of dragonflies as indicators improved at higher
taxonomic resolution and whether the turnover of dragonfly assemblages was
congruent with that of other groups.
Results Climate explained three times as much variation in turnover of
dragonfly species than dragonfly and other macroinvertebrate assemblages at
family level. The dissimilarity of dragonflies and varying turnover in each
macroinvertebrate assemblage meant surrogacy amongst groups were low.
Main conclusions On the basis of the influence of climate on turnover of
macroinvertebrate assemblages, dragonfly species distribution appears highly
sensitive to climatic factors, making this taxon a potential useful indicator of
climate change responses. However, the low surrogacy amongst assemblages
also suggests that a shift in the focus of conservation management from specific
taxa to the functional composition of assemblages across a diverse range of
habitats is needed.
... Among threatened wetland organisms, dragonflies (Odonata) have been widely proposed as indicators of the ecological quality of land-water ecotones, aquatic habitat heterogeneity (e.g., bank morphology and aquatic vegetation), and the hydrological dynamics of water bodies (e.g., Steyler and Samways, 1995;Clark and Samways, 1996;Chovanec and Waringer, 2001;Hawking and New, 2002;Schindler et al., 2003;D'Amico et al., 2004;Kadoya et al., 2004); thus, dragonflies are viewed as bio-indicators for the diversity and structure of the broader aquatic community (Briers and Biggs, 2003;Bried et al., 2007). The 200 resident dragonfly species in Japan are a major taxonomic component of floodplain wetlands (Sugimura et al., 1999). ...
Many Japanese dragonfly species depend on habitat complexes maintained in rice paddy systems. We postulated that recent alterations to habitat complexes in paddy systems have had adverse effects on dragonfly populations, especially those ‘once common species’ that have come to depend primarily on paddy systems following losses of natural floodplain habitats. A high proportion of Japanese lentic dragonfly species depends on paddy fields or agricultural ponds that have been extensively degraded, while lotic species can often use both paddies and natural river systems. Thus we also postulated that lentic species are more susceptible to changes in agricultural habitats and are subject to higher extinction risks than lotic species. We aimed to extend previous work on estimating dragonfly extinction risk by developing mechanistic insights into the processes involved. Postulates were tested by analyzing relationships between (1) previous quantitative extinction risk assessments for dragonfly species and (2) species’ ecological characteristics (i.e., distribution range and habitat type [lentic or lotic]). Lentic species were disproportionately represented among those with elevated extinction risk. Species with large distribution ranges were also subject to higher extinction risks than those with narrower ranges, reflecting a driving force acting at a national scale (i.e., intensive degradation of paddy systems).
... Monitoring goals may be diverse, including detecting population trends of threatened, endangered, keystone, or common species. Monitoring abundant resident (common) species may be crucial for detecting the early decline of habitats (Hawking & New, 2002). In this study, we focus on monitoring the abundance of common species locally (see further discussion on this issue in Appendix S1). ...
1. Standardised transect counts of butterflies in old-growth rainforests in different biogeographical regions are lacking. Such data are needed to mitigate the influence of methodological and environmental factors within and between sites and, ultimately, to discriminate between long-term trends and short-term stochastic changes in abundance and community composition.
2. We compared butterfly assemblages using standardised Pollard Walks in the understory of closed-canopy lowland tropical rainforests across three biogeographical regions: Barro Colorado Island (BCI), Panama; Khao Chong (KHC), Thailand; and Wanang (WAN), Papua New Guinea.
3. The length and duration of transects, their spatial autocorrelation, and number of surveys per year represented important methodological factors that strongly influenced estimates of butterfly abundance. Of these, the effect of spatial autocorrelation was most difficult to mitigate across study sites.
4. Butterfly abundance and faunal composition were best explained by air temperature, elevation, rainfall, wind velocity, and human disturbance at BCI and KHC. In the absence of weather data at WAN, duration of transects and number of forest gaps accounted for most of the explained variance, which was rather low in all cases (<33%).
5. Adequate monitoring of the abundance of common butterflies was achieved at the 50 ha BCI plot, with three observers walking each of 10 transects of 500 m for 30 min each, during each of four surveys per year. These data may be standardised further after removing outliers of temperature and rainfall. Practical procedures are suggested to implement global monitoring of rainforest butterflies with Pollard Walks.
... Las comunidades bióticas tanto de ecosistemas terrestres como acuáticos, son muy sensibles a las alteraciones del medio, sean éstas de origen natural o antrópico. En ecosistemas acuáticos; la cantidad de materia orgánica, el estado trófico del agua, la productividad, la sedimentación, el uso de fertilizantes y la contaminación química, entre otros procesos, determinan la composición, abundancia y diversidad de las comunidades acuáticas asociadas (Hawking & New 2002). La alteración de cualquiera de estos procesos, produce cambios en las características físicas y químicas del agua, y en consecuencia, cambios drásticos en las características ecológicas de las mismas. ...
The knowledge about population structure and dynamics of some neotropical species, especially those living in lotic systems is still barely studied. This study had the aim to assess if the conservation status of some lotic systems, is related to some demographic variables of P. gigantea, so this may be used as a model for ecological monitoring. For this, we evaluated the population structure of P. gigantea three times per month (almost one sampling event every eight days) in four streams of the state of Antioquia, Colombia, from March-June 2009. The specimens were collected using entomological nets along a transect of 200m in the littoral zone of each stream. The insects were marked on the wings and the population size was estimated with the mark-recapture method. Our results showed that the largest population size was recorded for the stream "La Catedral" with aprox 299 individuals, followed by the stream "La Doctora" with 218 individuals. Nevertheless, no significant differences in population size among the evaluated streams were found; and no statistical relationships were found between vegetation variables and the population size of P. gigantea. However, taking into account the limited dispersal capacity of P. gigantea, its survival in the studied streams was considered to be at risk, due to the continuous modification of large riparian forest areas, which cause the increase of forest patches, with different levels of interconnection, and hinder long-term permanence of populations.
... Insects belonging to Order Odonata (commonly known as dragonflies or odonates) are among the most suitable subject for any kind of nature observations and research (Corbet and Brooks 2008). Due to specific morphological characteristics, as well as behavioural and ecological peculiarities, they are often among the top selected invertebrate groups for environmental appraisals, wetland management plans preparation, monitoring programmes development and implementation (Clark and Samways 1996, King et al. 2000, Armstrong 2002, Chovanec et al. 2002, Hawking and New 2002, Briers and Biggs 2003, Clausnitzer 2003, Davies et al. 2003, Chovanec et al. 2004, Hadrys et al. 2005, Oertli et al. 2005, Scher and Thièry 2005, Thomas 2005. Below are some of the features that make dragonflies a priority group for nature conservation programmes and rapid biodiversity assessments: ...
A total of 32 Odonata taxa were found during the RAP-Fiji in the Nakorotubu range, Ra and Tailevu Provinces, Fiji. These taxa represent more than 50% of the all species recorded for the whole Fijian archipelago and about 78% of the species established for Viti Levu. The significance of the group for environmental appraisals is discussed, individual behavioural traits and short ecological information are provided for each species observed during the investigation, and a preliminary habitat classification scheme is suggested for the species collected from the study area. Due to problems with species taxonomy only general conservation recommendations are proposed without specifying local management actions that need to be taken.
INTRODUCTION
Insects belonging to Order Odonata (commonly known as dragonflies or odonates) are among the most suitable subject for any kind of nature observations and research (Corbet and Brooks 2008). Due to specific morphological characteristics, as well as behavioural and ecological peculiarities, they are often among the top selected invertebrate groups for environmental appraisals, wetland management plans preparation, monitoring programmes development and implementation (Clark and Samways 1996, King et al. 2000, Armstrong 2002, Chovanec et al. 2002, Hawking and New 2002, Briers and Biggs 2003, Clausnitzer 2003, Davies et al. 2003, Chovanec et al. 2004, Hadrys et al. 2005, Oertli et al. 2005, Scher and Thièry 2005, Thomas 2005). Below are some of the features that make dragonflies a priority group for nature conservation programmes and rapid biodiversity assessments:
Big, colourful insects, easily detectable and recognisable even in flight
Experienced observers could, in well studied regions, identify almost all species using a pair of binoculars only. Odonates cannot fold their wings along the body. That keeps them always above the surface and the researchers do not have to turn stones, chop tree bark, search among the leaflitter or dig into the soil to encounter these insects. Dragonflies can hide among dense vegetation however, their life-cycle always “brings” them close to the water bodies for reproduction.
Very specific behavior pattern, which keeps them close to the water
Dragonflies are easily found around wetlands of any kind. Some limits in their distribution and survival are posed by the areas in higher latitudes, fast flowing mountains streams, cold glacial lakes and highly saline coastal lagoons. Otherwise there could be up to 20–25 species encountered (in extremely good mixture of habitat types) during a single walk around water's edge. Normally much fewer occur near water.
Considerably small species number (compared to other insects groups)
With about 6000 currently described species Order Odonata ranks among the species poor insect orders. Low species number around wetlands is a prerequisite for developing effective monitoring programmes involving volunteers with no significant taxonomic knowledge. It is an important step in wetland management as dragonflies are often used as environmental indicators.
Very important indicators for habitat heterogeneity, pollution, species biodiversity, and global state of the environment
Dragonfly potential as bioindicators has long been recognised and recently assessed in Foot and Hornung (2005). Many aquatic biotic indices, overviewed in Chessman and McEvoy (1998), include odonates as well. Moreover there are biodiversity and habitat indices based entirely on this insect order (Schmidt 1985, Chovanec and Waringer 2001, Simaika and Samways 2009). Some species are very sensitive to habitat fragmentation and special “green corridors” are envisaged to harbour the vulnerable species (Van der Sluis et al. 2004).
This short overview is indicative of the significant role the dragonflies play in environmental studies. The recently prepared global assessment of all odonate species showed that one in 10 species is threatened with extinction (Clausnitzer et al. 2009). That increases the odonates' significance, raises their value in environmental assessments and makes their inclusion in the wetland monitoring programmes imperative especially for poorly studied regions.
The Nakorotubu Range, Viti Levu, Fiji, is among the poorest odonatologically known areas within the Fijian Archipelago. In spite of the 142-years history since the first published record for this part of the world the Odonata knowledge remains insufficient. Map 6 shows the total area coverage of the Fijian Archipelago compiled by published research within the region. A comprehensive literature overview follows, which is necessary for outlining the scientific tasks of the present research. It also acted as incentive for studying dragonflies within the Nakorotubu Range.
Brauer (1867a,b; 1869) appears to be the first recorder of the Fijian Odonata fauna. Six species are reported with no specified localities. Although claimed to be taken from “Viti- Inslen” not all have been sampled from Viti Levu (see Table 98.1). Around the same time Fijian islands appeared in the detailed monographs on the order made by Selys (1871, 1874) and other work of the same author (Selys 1891). He added seven new species with Nesobasis being an endemic genus for the country. Another new genus (Hypothemis) was introduced earlier by Karsch (1889). This monotypic genus is also endemic to Fiji.
Chronologically next in the list is Kirby (1890), however it is not included in Table 98.1 as it does not add new species to the study area. He makes a detailed catalogue of the whole order and refers to previously published records only. Three species (Orthetrum sabina, Pantala flavescens and Diplacodes trivialis) are overlooked and not included in his review. To avoid further misunderstandings and complicated taxonomic discussions other catalogues prepared for the world (Tsuda 1991, Bridge 1994) or regional (Schmidt 1938) fauna are omitted from this analysis.
Two other researchers make important contributions to the knowledge of Odonata fauna of the region in the beginning of the twentieth century. Martin (1901, 1906, 1914) and Ris (1909, 1911, 1916) add two more species to the Fijian Odonata fauna and provide important taxonomic notes on six previously known species. These works contain detailed synonymic lists compiled for the Odonata fauna from various regions worldwide and help in orienting the up-to-date dragonfly taxonomy.
Tillyard (1924) makes the first comprehensive review over the Fijian Odonata. He revises the Mr. Simmonds' (Government Entomologist in Fiji) collection taken mainly from two places on the southern part of Viti Levu Island. Prior to this investigation 17 species had been reported for Fijian islands not 16 as reported by Tillyard (1924) who possibly has overlooked a short note in brackets on Anax guttatus in Ris (1916). The results of Tillyard's study are an updated checklist with 15 new species for Fiji (11 of which were new to science), identification keys and morphological description of the endemic genus Nesobasis, general species distribution records and detailed zoogeographical analysis. The author introduces two more taxa Agriocnemis vitiensis and Nesobasis subhumeralis, however they were later synonymised in Fraser (1925) and Donnelly (1990) with Agriocnemis exsudans and Nesobasis angulicollis respectively and are excluded from Table 98.1.
Analysing the material collected by Miss Cheesman and Mr. Lever from the Pacific islands Kimmins (1936, 1943, 1953) report on 5 species sampled from Fiji. One of them was new to science.
Surprisingly the next new species for the Fijian Odonata fauna were published in a New Caledonian publication (Lieftinck 1975) after more than 30 years with no information about this archipelago. The author does not specifically refer to this fact however, reports about species global distribution reaching as far east as Fijian islands. On the same manner he mentions other 3 previously known species for the country.
About the same time the Fijian Odonata were “rediscovered” thanks to the intensified scientific expeditions within the area. Wise (1978) does not provide any species names and refers to all sampled material by order names only. Wise (1980) makes records on Auckland Museum's Odonata collection and provides accounts for 8 species with 2 new species for Fiji. Haynes (1987) investigated the benthic invertebrates on Viti Levu and reports on dragonfly larvae presented in the freshwater samples. However, the most important contributions came from researchers working in two different directions. They are the vital sources of information for the region and will be reviewed separately.
With a series of publications starting from this period on, Donnelly (1984, 1987, 1990, 1994, 2005) is presently the most recognisable expert on Fijian Odonata fauna worldwide. His contribution towards understanding Fijian Odonata is outstanding with considerable achievements in the taxonomy, chorology and biology aspects. We owe to his studies a new genus created for 3 previously described species and 4 new ones (three of which occur on Fijian islands and one on Vanuatu) (Donnelly 1984) and 10 other new species (Donnelly 1990) as well as detailed morphological descriptions and taxonomical analyses of the genus Nesobasis. The author's short notes about the trips within the Pacific islands (Donnelly 1987, 1994) are a real source of inspiration for further research. Of particular interest are remarks on the possible sex-role reversal and inferred parthenogenetic development in certain species noted in earlier publications and explicitly accounted for in Donnelly (2005). Male rarity is observed in species like N. campioni, N. flavifrons, N. monticola, N. rufostigma with no males encountered in N. flavostigma and N. caerulescens. Females of those species have been discovered establishing territories near the water edge together in the same manner as the males of closely related species.
The idea of sex-role reversal has been developed further and studied in greater detail by a team of co-associates. Their suspicions about parthenogetic development at least in two species (N. flavostigma and N. caerulescens), was firstly expressed in Sherratt and Beatty (2005). Later research paid special attention to Nesobasis species diversity and abundance (Beatty et al. 2007, Van Gossum et al. 2008) and confirm the male rarity in 13 species (Van Gossum et al. 2007). The members of the team also sampled 12 new species (Van Gossum et al. 2006, 2008) however, they had been already collected and were pending description by T. Donnelly. Thus they appear with abbreviations in the above mentioned publications and in Table 98.1.
Further general information on Fijian Odonata could be found in Evenhuis and Bickel (2005) and Evenhuis (2007) with no specific species name given and one molecular study where four Fijian species have been used as outgroups for studying phylogenetic history of the Hawaiian genus Megalagrion (Jordan et al. 2003). Molecular studies, aiming in exploring the evolution of the insular insect radiation, are another aspect of scientific work on Fijian Odonata. Although not officially published yet (only presented during scientific meetings) some research have been done by Chris Beatty on the relationships between Nesobasis and Melanesobasis and with other genera within the Pacific Ocean area.
The literature review revealed no odonatological data on the Nakarotubu Range. The closest region where dragonflies are known from is Wainidruku Creek, 2 km south of Wailotua Village (Donnelly 1990). Thus the Rapid Assessment Programme (RAP) was seen as important step towards contribution to faunal and ecological research of the order on the Fijian main island, Viti Levu. It aimed to establish species lists for the visited regions and make observations on the individual species habitat preferences. Species biology was considered also as highly important, however, for the limited time planned for each of the study areas little attention was paid to the diurnal activities relating to ovipositing, mating or roosting. However, some important data are collected and commented upon in this report.
MATERIALS AND METHODS
Adult Odonata (imago) were collected from three main areas in a total of 40 localities (Map 8) during the period 30 November — 12 December 2009. These include three places outside the Nakorotubu Range. All sites were sampled with aerial nets and captured individuals killed in 90% ethanol. Later, the specimens were dried at room temperature and transferred to paper envelopes. Some of them were prepared for further DNA analyses, the results of which will be published separately. Few freshly emerged individuals (tenerals) were collected together with the larval skin (exuviae). They were preserved for larvae description if it was found to belong to a species with unknown pre-imaginal morphological stage. Larvae were sampled in one locality only (number 25 from the list provided below).
The search for various biotopes and habitat types were planned after consultation with the local guides provided for the RAP. At each site the water edge was checked for flying individuals. The dense vegetation surrounding water bodies made it impractical for special transects to be made unless more time was spent within the study areas (Oppel 2006). The species activity was recorded and compared to what was known from the literature. The same was done for individual occupancy of the sites and observed preferences to sunlight vs shade. Various biotopes were visited with more attention paid to running waters. They were studied for suitable habitats for odonates based on presence/absence data and observed behavioural patterns. The Corbet (1999) system for distinguishing between biotope and habitat was adopted as it makes a clear separation with biotope being the entire ecological system providing specific living environments (habitats) for various living forms. These habitats must be defined by the production rate of the population, which must exceed the death rate in order for a population to be stable even without immigrants from other sources. Population estimations play a crucial role in defining species habitat parameters. However, these are laborious, time consuming and not applicable for rapid ecological investigations. For the purpose of the current research the habitat parameters were established based on records of possible breeding species only. As such, we defined species observed to: a) lay eggs, b) form tandems or copulating wheels, c) defend territories, or d) aggregate in large number. Breeding species (determined upon the larvae skin, newly emerged individuals or larvae prior to emergence) were excluded from the analysis as they need further identification work.
Sampling localities
• Lake by the Raintree Lodge, Colo-i-Suva (178°27′25.6″E; 18°03′30.4″S; 232 m a.s.l.): 30 November.
• Open grass vegetation on the hills above the lake by the Raintree Lodge, Colo-i-Suva (1787deg;27′21.9″E; 18°03′25.9″S; 260 m a.s.l.): 30 November.
• Olou River by Matuku Village (178°22′07.2″E; 17°37′47.0″S; 59m a.s.l.): 30 November.
• Oxbow lake of Olou River 860m straight line from Matuku village (178°21′56.5″E; 17°37′07.9″S; 52m a.s.l.): 30 November.
• Stream about 625m straight line S of RAP-Fiji Camp 1 site (178°21′59.3″E; 17°36′19.0″S; 142m a.s.l.): 30 November.
• RAP-Fiji Camp 1 site (178°21′52.0″E; 17°36′00.0″S; 170m a.s.l.): 01 December.
• Olou River about 280m straight line NW of RAP-Fiji Camp 1 site (178°21′44.3″E; 17°35′54.5″S; 145m a.s.l.): 01 December.
• Olou River about 420m straight line NW of RAP-Fiji Camp 1 site (178°21′41.9″E; 17°35′50.1″S; 145m a.s.l.): 01 December.
• Oxbow lake by Olou River about 455m straight line NW of RAP-Fiji Camp 1 site (178°21′40.8″E; 17°35′49.8″S; 161m a.s.l.): 01 December.
• Olou River about 610m straight line NW of RAP-Fiji Camp 1 site (178°21′39.2″E; 17°35′44.2″S; 165m a.s.l.): 01 December.
• Olou River about 735m straight line NW of RAP-Fiji Camp 1 site (178°21′41.3″E; 17°35′38.4″S; 170m a.s.l.): 01 December.
• Stream 710m straight line NW of RAP-Fiji Camp 1 site (1787deg;21′34.7″E; 17°35′44.4″S; 256m a.s.l.): 02 December.
• 13. Stream 1115m straight line NW of RAP-Fiji Camp 1 site (178°21′34.6″E; 17°35′27.9″S; no altitude recorded): 02 December.
• Olou River about 1925m straight line NW of RAP-Fiji Camp 1 site (178°21′21.7″E; 17°35′04.5″S; 214m a.s.l.): 02 December.
• On the inflow of Wainirea stream to Olou River (178°21′14.9″E; 17°35′00.1″S; 226m a.s.l.): 02 December.
• Stream about 875m straight line NW of RAP-Fiji Camp 1 site (178°21′25.4″E; 17°35′47.5″S; 295m a.s.l.): 02 December.
• Stream about 590m straight line S of RAP-Fiji Camp 1 site (178°21′51.5″E; 17°36′19.2″S; 150m a.s.l.): 03 December.
• Forest stream on the track to RAP-Fiji Camp 1 site at the beginning of the climbing from Olou River (178°21′57.3″E; 17°36′54.1″S; 129m a.s.l.): 30 November and 03 December.
• Pool by the Olou River about 695m straight line NW of Matuku Village (178°21′57.9″E; 17°37′26.3″S; 43m a.s.l.): 03 December.
• Olou River about 465m stream about 875m straight line NW of Matuku Village (178°22′00.9″E; 17°37′33.1″S; 34m a.s.l.): 03 December.
• Stream on the left-hand site on the track from Matuku village to RAP-Fiji Camp 2 site about 725m from the village (178°22′17.8″E; 17°37′25.8″S; 188m a.s.l.): 04 December.
• Stream on the left-hand site on the track from Matuku village to RAP-Fiji Camp 2 site about 1430m from the village (1787deg;22′34.9″E; 17°37′08.8″S; 347m a.s.l.): 04 and 07 December.
• Track from Matuku Village to RAP-Fiji Camp 2 site - top of the ridge (178°22′52.4″E; 17°36′27.7″S; 436m a.s.l.): 04 December.
• RAP-Fiji Camp 2 site (178°23′02.4″E; 17°35′53.4″S; 550m a.s.l.): 04 December.
• Stream passing by RAP-Fiji Camp 2 site about 270m straight line SW from the camp (178°22′59.9″E; 17°36′01.8″S; 499m a.s.l.): 05–06 December.
• Swampy area by the track to the coast about 1050m E-NE from the RAP-Fiji Camp 2 site (178°23′37.0″E; 17°35′45.7″S; 585m a.s.l.): 07 December.
• Namanu Creek about 500m E from Nasau Village (178°25′14.6″E; 17°44′02.6″S; 41m a.s.l.): 08 December.
• Wailotua River and adjacent oxbow lakes about 500m straight line SW from Nasau Village (178°25′20.3″E; 17°44′02.0″S; 40m): 08 December.
• Waimaca Creek about 300m S of Nasau Village (178°25′33.2″E; 17°43′55.2″S; 50m): 08 December.
• Nasau Village (178°25′23.6″E; 17°43′51.7″S; 45 m a.s.l.): 08–09 and 11 December.
• Wainalimata Creek on the track from Nasau Village to RAP-Fiji Camp 3 site (178°25′18.4″E; 17°43′27.6″S; 35m a.s.l.): 09 December.
• Wainamatavia Creek on the track from Nasau Village to RAP-Fiji Camp 3 site (178°25′12.6″E; 17°43′12.4″S; 55m a.s.l.): 09 December.
• Pool within the Nabunavonu area (178°25′18.2″E; 177deg;43′05.9″S; 10m a.s.l.): 09 December.
• Seepage within a densely vegetated area about 150– 200m S from RAP-Fiji Camp 3 site (178°25′19.1″E; 177deg;43′02.0″S; 27m a.s.l.): 09 December.
• Tributary of Wainivana River with a small waterfall (178°25′31.8″E; 17°42′44.5″S; 53m a.s.l.): 10 December.
• Swampy area by Wainivana River (178°25′43.2″E; 17°42′38.3″S; 67m a.s.l.): 10 December.
• Oxbow lake of Wainivana River (178°25′41.8″E; 17°42′42.7″S; 58m a.s.l.): 10 December.
• Tributary of Wainivana River (178°26′07.9″E; 17°42′35.0″S; 70m a.s.l.): 10 December.
• About 150–200 m downstream from the tributary of Wainivana River (178°26′07.9″E; 17°42′35.0″S; 70m a.s.l.): 10 December.
• 40. Suva — city garden (178°27′37.6″E; 18°07′24.4″S; 0m a.s.l.):): 12 December.
RESULTS
Species check list
A total of 32 Odonata taxa were found during the current research. Below is a complete species check list with short behavioural and ecological notes for each of them. It follows Evenhuis and Polhemus (2007) and is updated considering the recent taxonomic findings. Species are also arranged according to the occupancy of the sampling localities (Table 98.2). At least two more species could be added to this list however, their proper identification is pending.
Indolestes vitiensis (Tillyard, 1924)
• Localities: 2, 7, 15, 25, 26, 33.
• The species is confined to standing water bodies. It could be found around marshy areas at the sources of rivers or small vegetated pools formed along river banks by floods. Usually prefers shadow of the bushes and trees, but individuals were observed at areas with slight sunlight.
• I. vitiensis is endemic to Fiji and is widely distributed across the country.
Agriocnemis exsudans (Selys, 1877)
• Localities: 1, 2, 3, 7, 19, 28, 33.
• The species inhabits mainly stagnant waters, but is observed at the river edges in places where the flow is reduced or nearly absent. It chooses submerged vegetation areas and could be present at sunny and shady areas near the water surface. Mating pairs were observed at such locations as well.
• A. exsudans is widely distributed across the Pacific ranging from New Caledonia to Tonga. It is rarely reported for Fiji.
Ischnura aurora (Brauer, 1865)
• Localities: 3.
• It is a delicate species whose females could be overlooked in nature. However, males possess brightly coloured bodies and are easily detected during field researches. Typical inhabiting areas include stagnant waters overgrown with vegetation, but the species was observed along the river bank during this survey.
• I. aurora is an eurytopic species that is well adapted to various environmental situations. It occupies a wide range of the Pacific (Australia to Tonga) and is reported from SE Asia as well. Only five previous records are known for Fiji with just one specified location.
Ischnura heterosticta (Burmeister, 1839)
• Localities: 11, 20, 28.
• The species inhabits stagnant waters. Single individuals were observed during this survey along some of the study rivers without any evidence of breeding.
• I. heterosticta has a wide distribution across the Pacific and is also reported from various locations on the islands of Viti Levu and Vanua Levu.
Melanesobasis corniculata corniculata (Tillyard, 1924)
• Localities: 12, 15, 25, 34, 35.
• This dark bodied species was usually found near the river edge perched on twigs or leaves hanging just above water surface. In those areas it was well concealed and difficult to observe as in some occasions the individuals preferred shady areas.
• M. corniculata is endemic to Fiji. It is widely distributed within Fijian archipelago and is known from various island groups.
Melanesobasis flavilabris (Selys, 1891)
• Localities: 13, 16, 25, 27, 31, 32, 35, 38.
• No preferences were observed for this species. Individuals were encountered in various habitat types ranging from sunny areas near river edges, underside of stones or big rocks away from the water, bushes and grass vegetation around temporary pools, vegetated locations beneath tree canopies, and around small waterfalls. M. flavilabris is endemic to Fiji. It is known from various localities across Viti Levu and a single place from Vanua Levu.
Melanesobasis mcleani (Donnelly, 1984)
• Localities: 12, 15, 34.
• The species was observed only in shady parts of small streams or seepage waters. It was found in three places with single individuals.
• M. mcleani is endemic to Fiji and only reported from Viti Levu. Previous observations are scarce and come from two specific locations only.
Nesobasis angulicollis (Tillyard, 1924)
• Localities: 6, 9, 14, 15, 25, 29, 31, 38.
• The species was observed at various areas along the rivers and streams. No specific requirements were recorded as the individuals were encountered at both sunny and shady regions perching on twigs and leaves or flying around exposed bounders. The stream current seems to be of no particular importance either because N. angulicollis individuals from both sexes (including mating pairs and tandems) were sighted along gradients of stream flows.
• N. angulicollis is an endemic to Fiji. It has been recorded from all over the main island of Viti Levu.
Nesobasis caerulescens (Donnelly, 1990)
• Localities: 22.
• The only record during the current research comes from a shady stream with slow to almost no visible water current. A single female was collected perched about one metre above the ground on a tree twig far from the stream edge. This record is insufficient to make any conclusions about the species preferences to the local environment.
• N. caerulescens is endemic to Fiji. It is known from single locations only and is represented by low numbers of specimens.
Nesobasis campioni (Tillyard, 1924)
• Localities: 21, 28, 32, 35.
• The species was observed only in shaded parts of the streams predominantly flowing on the bottom of deep gullies. A single male and three females were observed without any evidence for autochthonous.
• N. campioni is endemic to Fiji. It is previously confirmed from all over Viti Levu, Ovalau and Wakaya islands.
Nesobasis comosa (Tillyard, 1924)
• Localities: 8, 15, 16, 17, 18, 21, 25, 29, 31.
• Further identification and comparison with N. heteroneura is needed to establish the true status of N. comosa within Nakorotubu Range. Specimens with typical comosa morphological features were collected from lowland areas to mountain regions. However, the species is known as inhabitant of higher regions, while heteroneura is collected mainly from lower altitudes. N. comosa is endemic to Fiji. It is distributed all over Viti Levu.
Nesobasis erythrops (Selys, 1891)
• Localities: 5, 10, 14, 15, 16, 17, 18, 21, 25, 29, 31, 32.
• No preferences to specific habitat type were observed. It was found in both sunny and shady areas along water edge. Tandems and single individuals were encountered perched on exposed boulders at the river bank, high on the tree twigs, or leaves above the water. Males seemed to occupy territories as they attacked other conspecific and heterospecific (N. comosa) males. Underwater oviposition was observed in a single occasion with the female laying eggs in the mosses guarded by its mate. During a night walk a male was detected inside forest about 500 m from the water edge hanging on a leaf edge at about 2.5 m above the ground.
• N. erythrops is endemic to Fiji. It is recorded from all over Viti Levu Island.
Nesobasis flavifrons (Donnelly, 1990)
• Localities: 9, 13, 22, 25 (downstream from this locality).
• Only females collected. Pre-oviposition behaviour and actual oviposition were observed. Both took place in shady areas. Prior to oviposition females were flying about 10 cm above the water surface in slow motion faced towards stream banks. It looked like they checked the banks before made a decision to stay for oviposition. They laid eggs unguarded in the dead plant material floating on the water surface.
• N. flavifrons is endemic to Fiji. It was previously reported from 6 localities only on Viti Levu Island.
Nesobasis heteroneura (Tillyard, 1924)
• Localities: 29, 32, 35.
• This species is listed here based on some females collected during the study however, further confirmation is needed as no sure evidence is known for distinguishing between heteroneura and comosa females. It is possible that all specimens observed within the Nakorotubu Range belong to comosa only.
• N. heteroneura is endemic to Fiji. It is reported from Northern and Southern Viti Levu, Ovalau and Wakaya Islands.
Nesobasis leveri (Kimmins, 1943)
• Localities: 25.
• The species was found in both high mountain regions and lowland areas. More individuals were observed at higher altitudes. It was confined mainly to mixed shadow/sunlight areas of fast flowing streams.
• N. leveri is endemic to Fiji. It was previously reported from two localities only.
Nesobasis longistyla (Selys, 1891)
• Localities: 9, 14, 15, 25, 34, 38.
• The species is a stream dweller found predominantly in shady areas. There was a single observation from an oxbow lake, however no proof of breeding was observed.
• N. longistyla is endemic to Fiji. It is previously reported from all over Viti Levu and Kadavu Islands.
Nesobasis monticola (Donnelly, 1990)
• Localities: 25.
• A single female was observed at a fast flowing section of a mountain stream. No evidence for breeding was recorded.
• N. monticola is endemic to Fiji. It is previously reported from Northern Viti Levu and Ovalau Islands.
Nesobasis pedata (Donnelly, 1990)
• Localities: Not specified.
• Two male specimens obtained only. One of them (A. Caucau leg.) was encountered on 03 December in the forest between localities 3 and 6 at altitude of about 350 m. The second is a dubious young specimen with unclear morphological features. It was found on 04 December close to locality 24 (indicated with a question mark in Table 98.2) along the stream above the RAP_Fiji Base camp 2 site. No coordinates were taken of both localities.
• N. pedata is endemic to Fiji. It is previously reported from four localities.
Nesobasis rufostigma (Donnelly, 1990)
• Localities: 25, 27, 29, 39.
• Females were observed flying in the middle of the streams and rarely in very shady areas. They appeared in sunny parts of the stream.
• N. rufostigma is endemic to Fiji. It was previously reported from a wide range on Viti Levu, Kadavu, Ovalau and Koro Islands.
Nesobasis selysi (Tillyard, 1924)
• Localities: 9, 25, 29, 31, 32, 35, 39.
• This species was observed mainly in lowland areas, flying along stream banks around exposed boulders and between tree branches.
• N. selysi is endemic to Fiji. It was previously reported from all over Viti Levu and Ovalau Islands.
Nesobasis telegastrum (Selys, 1891)
• Localities: 9, 12, 13, 22, 34, 38.
• The species was only observed in shady areas. It occupied slow flowing streams and in a single occasion was located near an oxbow lake.
• N. telegastrum is endemic to Fiji. It was previously reported from 8 localities on Viti Levu Island.
Anax sp
• Localities: 14.
• The species was also observed at many sites along the entire stretch of Olou River within the study area (between localities 6 and 15). Flying individuals were observed only, which made precise identification of the species impossible. Ris (1916) recorded A. guttatus from Fiji without specifying location. Possibly the same species occurs within the Nakarotubu Range however, further prove is needed from collected specimens and proper identification.
Hemicordulia sp
• Localities: 4, 7, 11, 14, 28.
• Flying individuals were encountered also in other sites along the main transect at Olou River. They mainly hovered over the pool-like sections of the river formed by the slow moving waters kept between the large boulders and rocks. No species identification is possible at this stage. Only two males were collected only and they need to be properly keyed out considering previous research done on Fijian Odonata as well as other regions within the Pacific. It is possible that it belongs to an undescribed species.
Procordulia irregularis (Martin, 1906)
• Localities: 25.
• The single location for this species was a fast flowing stream situated at high altitude. Males did not appear to be territorial as they passed over the water surface with a fast flight with short-time hovers. A single ovipositing female was observed. She was laying eggs unguarded by dipping her abdomen into a section of the stream with almost no water current. It was shaded completely by the surrounding vegetation and was close to some large bounders.
• P. irregularis is endemic to Fiji. It was previously recorded from two localities only on Viti Levu and Vanua Levu Islands.
Diplacodes bipunctata (Brauer, 1865)
• Localities: 3, 19, 23.
• The species is known as inhabitant of pools, lakes and other stagnant water bodies. It occupies oxbow lakes and that was naturally seen along rivers and streams during the current study. In these areas it often perched directly on stones, but mainly preferred the bank vegetation.
• D. bipunctata has a wide distribution across the Pacific. It was rarely reported before and is known from Viti Levu and Lau island group with only one specified locality.
Hypothemis hageni (Karsch, 1889)
• Localities: 25, 36.
• Observed on two consecutive days at locality 25. Female laid eggs unguarded near boulders. She chose parts of the stream with visible strong current. Males were observed for a very short period. They appeared to be very shy and stayed perched for few seconds only. Tree leaves were chosen as perching substrate and they kept themselves on about 2 metres above the surface.
• H. hageni is a monotypic genus endemic to Fiji. It has been very rarely reported before and is known from Viti Levu and Vanua Levu with one specified location.
Lathrecista asiatica (Fabricius, 1798)
• Localities: 28.
• The species was collected also from another area - on the track to the Base camp 2 site above locality 21. No coordinates were taken as the single male was obtained far from any typical habitat for the species. It is known as inhabitant of stagnant waters and was confirmed from an oxbow lake of Wailotua River. Observation were made of males defending territories perched on the end of dead tree branches at the lake edge.
• L. asiatica has a very wide distribution from SE Asia across the Pacific. It was previously reported from Viti Levu, Vanua Levu and the Lau group however, only two precise locations are given in the literature and single specimens were collected from those sites.
Orthetrum serapia (Watson, 1984)
• Localities: 2, 3, 7, 15, 17, 19, 28.
• The species status within Fiji must be revised. So far almost all previous records have been on the closer species O. sabina. After the Watson (1984) revision, the new species O. serapia was erected for large number of specimens collected across Pacific. It is likely that all previous records on sabina from Fiji should be assigned serapia. Only O. seraia was observed during the current study. Some locations are given above however, individuals were recorded from the entire stretch of Olou River in various habitat types. Preferences were given to stagnant water bodies and flying individuals were often seen moving between those over the river surface.
• O. serapia is distributed from SW Pacific to the Philippines. It was previously reported only once from Viti Levu, however when the true status is confirmed it may appear that it is more widely distributed. So far O. sabina was collected from Viti Levu, Ovalau and the Lau group.
Pantala flavescens (Fabricius, 1798)
• Localities: 30, 40.
• No specific preferences were observed for this species. Two locations are given here as one is from the city garden of Suva, but P. flavescens could be easily seen in many other areas. Normally individuals chose open areas among the tree and bush vegetation. They could fly well over large open fields and hover above the grasses. P. flavescens is a cosmopolitan species. It was previously only reported from the Lau group.
Rhyothemis phyllis subsp. dispar (Brauer, 1867)
• Localities: 2, 19.
• The species is a typical inhabitant of stagnant water bodies. Males selected sites around the water edge and perched on the top of dead twigs exposed to sunlight. A freshly emerged female was collected from the top of a hill above a large lake. It was perched low on the ground at the base of the grass vegetation.
• R. phyllis ranges widely in the SE Asia and the Pacific. It forms various subspecies as R. p. dispar is endemic to Fiji. Previous records are very rare and no specific location has been ever reported.
Tholymis tillarga (Fabricius, 1798)
• Localities: 37.
• The single observation comes from an oxbow lake of Wainivana River. The individual was observed for few seconds perched on the grass vegetation. No further records were made although the area was investigated continuously during the day.
• T. tillarga is very widely distributed from SE Asia and across the Pacific. A male was previously reported from Viti Levu with no specified location.
Tramea transmarina (Brauer, 1867)
• Localities: 19.
• The species occurred at similar places as P. flavescens, however it is normally observed with fewer individuals compared to cosmopolite species. During the current research Tramea sp. were observed flying together with P. flavescens and were believed to be T. transmarina as that is the only species previously reported from the genus for Fiji and a male of the same species was collected from the above mentioned locality. At that place it chose to perch on the top of dead twigs near water edge.
• T. transmarina is known from other Pacific islands, like New Caledonia and Kermadec. It was previously reported from two authors with no specified locations.
Habitat types
The following types of habitats were considered as odonatologically important within the Nakorotubu Range. They are arranged according to the visual stimuli that are believed to be crucial in habitat selection (commented in Beschovski and Marinov 2007) and this arrangement does not necessarnecessarily reflect the perceived significance of the habitats. A final conclusion must be drawn upon more consistent research involving equal amounts of time and effort for all biotopes and considering the altitude. Each habitat is described with few examples of their occupants and a code name that is used later in the discussion.
H0 Seepage water with almost no visual current flowing through closed forest floor. Inhabited by Melanesobasis mcleani, Nesobasis flavifrons, N. longistyla, N. telegastrum.
H1 Springs flowing at the bottom of shady gullies between boulders and cobbles thus forming small waterfalls downhill. Inhabited by Melanesobasis corniculata, M. flavilabris, Nesobasis comosa.
H2 Streams with scarce submerged aquatic vegetation flowing through regions with mixed shade/sunlight areas between large boulders. Inhabited by Nesobasis leveri, N. longistyla, Procordulia irregularis, Hypothemis hageni.
H3 Permanent pools formed between exposed to sunlight boulders of streams and rivers. Inhabited by Hemicordulia sp., Diplacodes bipunctata, Orthetrum serapia.
H4 Exposed boulders on river beds and large rocks by the banks. Inhabited by Melanesobasis flavilabris, Nesobasis eryhrops, N. angulicollis.
H5 Mixed shade/sunlight vegetated areas by the river banks. Inhabited by Agriocnemis exsudans, Ischnura heterosticta, Orthetrum serapia.
H6 Permanent oxbow lakes by the rivers with partly shaded water edge. Inhabited by Indolestes vitiensis, Agriocnemis exsudans, Lathrecista asiatica.
DISCUSSION
In spite of the long history of studies on Fijian odonates dating back to 1867, the species taxonomy posses serious problems for any investigator. The great diversity of endemic species and morphological forms observed in a comparatively small territory among the members of genus Nesobasis is probably the biggest challenge. It is, perhaps compatible only with the Hawaiian genus Megalagrion (Jordan et al. 2003). This makes it impossible to prepare any final suggestions about the exact species number inhabiting the Fijian archipelago. Moreover, new taxa have been found and are under description at the moment (Donnelly, per. com.). In Table 98.1 they are listed with abbreviation of the possible species name that will be assigned. In the same table it is indicated that at least 61 odonate species are known to occur on the Fijian islands. This number will surely increase in future with more investigations taking place within those interesting areas.
The species list provided above contains more than 50% of the total Odonata fauna known from all islands within the Fijian archipelago, some of which are endemic to islands other than Viti Levu. If however, only Viti Levu taxa (41 species) are included in the analysis the significance of Nakorotubu Range increases significantly to containing about 78% of the odonate species occurring on the island.
It is difficult to classify the habitat types according to their significance for odonates. Some of them were checked for several minutes only on the way to and back from the Base camps while others were investigated over two consecutive days. Moreover, a single locality may support several habitats. Locality 25, for example, was visited twice and it combines habitat types H1, H2 (predominantly) and partly H3, which combined record the highest number of species observed during the investigation (Table 98.2). Species conservation status is another aspect that must be considered for the habitat evaluation scheme. H0, for example, may support low species numbers, but being of high importance (represented with low specimen numbers on other sampling occasions or with limited distribution) those species may increase the significance of the habitat in the generalised classification scheme. That is why a weighted approached is suggested where the habitats gain different values according to various criteria including: a) species population size, b) species global and regional distribution, c) species ecological preferences, d) habitat availability within the investigated region, and e) threats over habitat integrity and heterogeneity. Such estimation is impossible at the present stage. It needs thorough investigation over the region, which to confirm or reject the proposed basic habitat classification scheme. It may or may not be valid for the region in question, however it must be compared with other areas in order to achieve a better understanding of the habitat availability and species occupancy among them.
CONCLUSIONS AND CONSERVATION RECOMMENDATIONS
Future survey recommendations
Based on the results of this survey, the following general recommendations are proposed:
• Intensified taxonomic work for establishing the true specific status of Fijian Odonata. In some occasions a clear separation between species is not always possible in the field and requires further lab work. Identification keys for Fijian species need to be updated with more reliable features for distinguishing between closely related species. They must be combined with detailed investigation on the intraspecies morphological diversity and DNA analysis in order to establish the actual species diversity.
• Re-evaluation of the species diversity of Fijian archipelago. It is necessary that the specimens so far collected from the country to be checked in regard to the new taxonomic findings. Special attention was paid above to the Orthetrum sabina/serapia situation. Other species that must be treated with special attention include Agriocnemis exsudans, Ischnura heterosticta, Tramea transmarina as well as species with unclear taxonomic position, like Hemicordulia sp.
• Mapping odonate distribution within Fijian islands. Visualisation of the data compiled for species distribution always helps in establishing gaps in the research, outlining future initiatives and planning urgent conservation measures. Such a mapping scheme is imperative and must be considered as a baseline for any study.
• Combining the mapping scheme with environmental variables and biological/ecological data for producing predictive habitat models for each species. It is considered as the pinnacle in the preliminary conservation planning process. Predictive habitat models could reveal the landscape features that approach the individual species requirements to the local environment. They, in combination with environmental variables and land use data, would visualise the potential of the local environment for supporting the habitat diversity and related species.
Conservation recommendations
The above points are fundamental questions to be answered for any organisation that plans future Odonata related activities within the Nakorotubu Range. Unfortunately prior to the clarification of these main points no specific recommendations could be made for in situ protection of Odonata species within the Nakorotubu Range. Any specific suggestion requires understanding of the biology and ecology of the species and identifying the potential threats to their natural habitats. The lack of this data makes it very difficult to predict the potential threats to odonates inhabiting the Nakorotubu Range. During the this survey no significant anthropogenic disturbances, like pollution, drainage, intensive harvesting or farming, were recorded. The tracks towards the Base camp sites 1 and 2 were reasonably well maintained however, some parts were hard to follow and according to the local guides were much reduced in size due to under exploration. This is a good indication that the Nakorotubu Range Odonata possibly experience low human pressure. The most worryingsituation was found at the upper section of Olou River near the inflow of Wainirea Stream. Some oil-like spots of unidentified origin were recorded on the water surface. The whole section of Olou River from Base camp 1 site to this point was characterised by intensive algae growth which had developed over the stones and some pool-like sections of the river. It could well be a natural nutrient enrichment or a consequence of effluent waters discharged from tributaries of the main river.
Table 8.1: Chronological literature review of Odonata records from Fiji.
Table 8.1 Contn'd
Table 8.2: Total number of Odonata species per locality.
Table 8.2 Contn'd
Notes
[] Team members: Samuela Mocelutu, Remisio Turaga and Mitieli Luvuluvuwaqa.
REFERENCES
1
2
3
BeschovskiV. M.Marinov 2007Fauna, Ecology, and Zoogeography of Dragonflies (Insecta: Odonata) of Bulgaria.In FetV. A.Popov Biogeography and Ecology of BulgariaSpringer199231Google Scholar
4
5
6
7
BridgesB. 1994Catalogue of family-group, genus-group and species-group names of the Odonata of the world (third edition).Urbana, IllinoisC.A. Bridgesxiv 951Google Scholar
8
9
10
11
12
13
14
15
16
CorbetP. S.Brooks 2008Dragonflies.Collins454Google Scholar
17
18
19
20
21
22
23
24
EvenhuisN. D.Polhemus 2007Checklist of Odonata of Fiji.Bishop Museum Technical Report3515available at: http://hbs.bishopmuseum.org/fiji/pdf/tr38%2815%29.pdf Google Scholar
25
26
27
28
29
30
31
32
33
34
35
36
KirbyW. 1890A synonymic catalogue of Neuroptera Odonata, or Dragonflies with an appendix of fossil species.LondonGurney and JacksonIX+202Google Scholar
37
38
39
MartinR. 1906Collections Zoologiques du Baron Edm. de Selys Longchamps, Catalogue Systematique et descriptif.CordulinesFascicule XVII94Google Scholar
40
41
42
43
RisF. 1909Collections Zoologiques du Baron Edm. de Selys Longchamps, Catalogue Systematique et descriptif. Libellulinen monographisch bearbeitet. Vol. 1.Fascicule IXGoogle Scholar
44
RisF. 1911Collections Zoologiques du Baron Edm. de Selys Longchamps, Catalogue Systematique et descriptif. Libellulinen monographisch bearbeitet. Vol. 2.Fascicule XII, XIII, XIVGoogle Scholar
45
46
47
48
49
50
Selys-LongchampsE. de. 1891Causeries odonatologiques. No. 3. Nesobasis Selys (Nouveau sous-genre d'Agrionines). Comptes Rendus des Seances.Societe de Entomologie de BelgiqueLILVIIGoogle Scholar
51
52
53
54
55
Vander SluisT. M.Bloemmen I.Bouwma 2004European corridors: Strategies for corridor development for target species.ECNCAlterra32Google Scholar
56
Van GossumH. C.Beatty T.Sherratt 2006The Zygoptera of Viti Levu and Vanua Levu, the two larger islands; in the Fiji archipelago.IDF-Report 9114Google Scholar
57
58
59
60
61
Notes
[] Team members: Samuela Mocelutu, Remisio Turaga and Mitieli Luvuluvuwaqa.
... Additionally, climate change may already be forcing changes in odonate distribution and life history (Paulson, 2001;Hickling et al., 2005;Hassall et al., 2007;Flenner & Sahle´n, 2008;Hassall & Thompson, 2008;Ott, 2008). As many researchers (Corbet, 1993;Primack et al., 2000;Sahle´n & Ekestubbe, 2001;Briers & Biggs, 2003;Hawking & New, 2003;Hornung & Rice, 2003;Foote & Hornung, 2005;Bried et al., 2007;Flenner & Sahle´n, 2008;Samways, 2008;Clausnitzer et al., 2009;Reece & McIntyre, 2009) have suggested or shown that the Odonata are valuable as conservation flagships and umbrellas, or as indicators of aquatic biodiversity, habitat quality, and ecological change, one may reasonably expect them to feature prominently in state wildlife action plans. However, even the charismatic and well-studied 'microfauna' are often overlooked or underrepresented in mainstream conservation efforts in the U.S. and abroad (Bossart & Carlton, 2002;Clark & May, 2002;Leather, 2009). ...
1. The overarching goal of United States wildlife action plans is to prevent wildlife from becoming endangered or declining to levels where recovery becomes unlikely. Effective plan implementation depends on establishing Species of Greatest Conservation Need (SGCN), defined as wildlife species with small or declining populations or other characteristics that make them vulnerable.
2. Although nearly two‐thirds of distinct Odonata species known from the U.S. (441 species as of 2005) were appointed as SGCN, over half the states neglected to assign dragonfly SGCN, damselfly SGCN, or both. Western and southern states listed proportionately fewer odonate SGCN than states of the Great Lakes, Mid‐Atlantic, and New England regions, apparently reflecting geographic patterns of legal authority, available information, and involvement by Odonata specialists.
3. Greater consultation of Odonata specialists is encouraged in any revision of state wildlife action plans, along with increased: (i) use of existing conservation lists, (ii) inferences from field guides and major faunal synopses, (iii) recognition of patterns of endemism, and (iv) application of empirical species distribution modelling.
4. Legal and management restrictions aside, insects and other invertebrates are often neglected in mainstream conservation efforts because they are perceived as understudied. It is erroneous to assume ‘not enough information’ exists for well‐studied microfauna such as Odonata and doing so further undermines the conservation of less conspicuous and charismatic taxa.
... We selected aquatic macrophytes, Odonata, and benthic macroinvertebrates as the focal taxa, all of which are considered to be indicators of healthy biodiversity in freshwater ecosystems (e.g., Engelhardt and Ritchie, 2001;Heino, 2002;Heino et al., 2003;Declerck et al., 2005;Ilmonen and Paasivirta, 2005;Kadoya et al., 2009;Simaika and Samways, 2009). In particular, we selected Odonata as a single group from macroinvertebrates because among aquatic organisms, odonates have been widely proposed as indicators of the ecological quality of land-water ecotones, and aquatic habitat heterogeneity (e.g., Steyler and Samways, 1995;Clark and Samways, 1996;Chovanec and Waringer, 2001;Hawking and New, 2002;Schindler et al., 2003;D'Amico et al., 2004;Kadoya et al., 2004). ...
One of the promising approaches to monitoring biodiversity is assessing the status of pressures driving the biodiversity state. To achieve this, we need to identify the principal pressures that cause simultaneous biodiversity loss across taxonomic groups and clarify how multiple pressures act synergistically or at least simultaneously to decrease biodiversity in the focal ecosystem. Here, we used a series of 64 ponds as a case study and we developed a framework for an integrated biodiversity indicator that took into consideration the estimated relative importance of multiple pressures. The indicator is defined as a function of the pressure(s) and is parameterized to explain a number of individual indicators of biodiversity, such as richness, abundance, and functional diversity of focal taxa. We selected aquatic macrophytes, Odonata, and benthic macroinvertebrates as the focal taxa. In addition, we focused on three types of pressure: eutrophication (represented by total phosphorus, total nitrogen, suspended solids, chlorophyll a, and density of cyanobacteria of pond water), habitat destruction (land-use type around the pond and pond bank protection), and invasive alien species (abundance of bluegill, largemouth bass, red swamp crayfish, and American bullfrog). We then evaluated the relationships among direct pressures and the individual biodiversity indicators and used a hierarchical Bayesian approach to calculate the integrated biodiversity indicator. Using this framework, we demonstrated that eutrophication had greater effects on the state of biodiversity of the agricultural ponds than did habitat destruction or the presence of invasive alien species. We also showed that the integrated indicator could well explain the behaviors of several individual biodiversity indicators, including total richness, endangered species richness, and functional diversity of focal taxa. These results demonstrate the advantages of the framework in providing a more practical method for assessing biodiversity, and quantifying the relative importance of the major threats to biodiversity to prioritize strategies in conservation planning and policy making.
... The above mentioned characteristics make dragonflies, especially the adults, valuable candidates for medium to long-term monitoring programs (Smith et al., 2007). Monitoring abundant resident species may be important for detecting the early decline of a habitat (Hawking and New, 2002), while monitoring rare species can be indicative of relict or undisturbed conditions and used to rate the importance of a site (Eyre et al., 1986). ...
Monitoring changes in population levels of a wide range of species in biodiversity research and conservation requires practical, easy-to-use and efficient assessment and monitoring methods. Dragonflies (Insecta: Odonata) are a valuable tool for assessing aquatic systems and have been used as indicators of ecological health, ecological integrity, and environmental change, including climatic change, as well as indicators of habitat recovery. We field-tested a freshwater ecological integrity index, the Dragonfly Biotic Index (DBI), based on dragonfly assemblages at the local scale, and compared the DBI to a biodiversity index (average taxonomic distinctness, AvTD) as well as to a standard freshwater benthic macroinvertebrate-based freshwater health index (South African Scoring System, using Average Score Per Taxon, ASPT). We sampled 20 river sites, selected a priori. Adult dragonflies and benthic macroinvertebrates were collected using standardized methods. Environmental variables were collected in situ, and water samples taken. Temperature and pH were the most important physical environmental variables in explaining the assemblage structure, and we found significant abiotic–biotic relationships, as well as biotic–biotic relationships. Overall, dragonflies were more sensitive to changes in river condition than were macroinvertebrates, in part because they were responding at the species rather than higher taxonomic level. AvTD scores did not show any significant relationship with changes in river condition. Furthermore, sites with low biotic scores (indicating disturbance) had high AvTD values. In contrast, DBI site value and ASPT scores were highly significantly correlated. We conclude that dragonfly assemblages in the form of a DBI are an excellent tool for environmental assessment and monitoring freshwater biodiversity, with the potential to replace labour-intensive benthic macroinvertebrate-based freshwater quality assessments, such as SASS.
Wildlife intrusion into human settlement and residency has long been viewed as a disturbance rather than regarded from other perspectives, such as wildlife welfare or conservation. Insects were part of that wildlife that were considered as pests or nuisances whenever their existence intersected with human livelihood. In this study, we documented a year-round (August 2019 to August 2020) observation of dragonflies intruding into a residence in the densely populated urban area in Padang City, West Sumatra, Indonesia. The study used the descriptive method, where the data was recorded from any occasion an individual or more dragonflies entered the house. The observation recorded the date and time of entry, species identification, and sex which was later analyzed. During the observation, we recorded 41 individuals entering the residence. They were classified into two damselfly species (Zygoptera) and ten valid dragonfly species (Anisoptera). Orthetrum sabina, Tholymis tillarga and Gynacantha dorhni became the most recorded species with 8, 7, and 7 total individuals, respectively. With 12 individuals recorded in a month, February 2020 was the most dragonfly-intruded period, much higher than the intrusion rate of 2.8 individuals per month. Dragonflies were observed entering the residence at midday (10 individuals), afternoon (12 individuals), evening (11 individuals) or night (8 individuals); this might suggest that night lighting might be what caused them to get into the residence. Both sexes were equal (18 females, 20 males, and three unsexed). The availability of tiny prey insects within the settlement area is another causative factor in this phenomenon. This intrusion should be alarming that the urbanization processes need to be reconsidered to be more ecological-friendly.
Hydrophylita neusae n. sp. is described and illustrated. Hydrophylita is a small genus of Trichogrammatidae which now includes four species, all known to attack eggs of damselflies (Odonata: Zygoptera). A key to species is included and those known from the Neotropics are illustrated.
Dragonflies are globally renowned bioindicators, with larvae, exuviae and/or adult life stages used in freshwater quality assessments. However, little is known about the extent to which conspecific adults and larvae occur within close proximity of each other, or how they comparably respond to biotic and abiotic factors. Firstly, we test the extent to which adult male dragonflies are congruent with their larvae at three independent sample unit scales (small 10 m × 3 m, medium 90 m × 3 m, and large 450 m × 3 m) along four rivers, along with a subset of 40 randomly selected small scale sites (small 40) to test for a possible effect of sampling design on the outcomes of the spatial scale analyses. Secondly, we test the extent to which adult males and larvae share similar responses to environmental variables. At medium and large spatial scales, larvae and adults were strongly congruent for abundance, species richness, and Dragonfly Biotic Index (DBI) scores. Despite this, at the small spatial scale, only 15% of observations matched (contained adults and conspecific larvae). This increased to 46% at the medium scale, and 60% at the large scale, neither of which were significantly different from the number of mismatches. Dragonfly species composition differed between larval and adult assemblages at the small, small 40, and medium scales but did not differ at the large scale. Water temperature was the only variable that generally elicited similar responses in both life stages, at all spatial scales. Exuviae here were so under-represented that they provided no extra information. Assessments, where medium or large spatial scales are suitable for sampling, such as measuring the state of a river, can utilize either life stage. However, for comprehensive biodiversity surveys, both larvae and adults should be sampled.
The enormous ecological and taxonomic variety of aquatic insects, many of them endemic and localised in occurrence in Australia, is still to be appreciated fully. Many of the ‘rarer’ freshwater insects in Australia occupy equally restricted habitats, whose loss and degradation pose the most severe threats to those insects, with many of those threats continuing to increase insect vulnerability.
For dragonflies, the final exuviae are the most identifiable nymphal stage, can substitute for lethal processing of live animals, and definitively indicate life-cycle completion or reproductive success. However, dragonfly exuviae are difficult to find and identify relative to adults, and species richness in exuvial surveys is generally biased low. We tested readily acquired information in adult surveys as indicators of exuviae presence and, therefore, species residency. Repeated concurrent surveys of adults and exuviae were completed at 32 wetlands in New York and 30 wetlands in Oklahoma, USA. We modeled the occurrence of exuviae as logit-linear functions of adult abundance, detection frequency (across surveys), teneral frequency, and frequency of breeding behavior while controlling for imperfect detectability. Exuviae occupancy probabilities suggested several reliable indicators of species residency: 1) finding adults on >= 4 surveys, 2) finding tenerals on >= 2 surveys, and 3) counting >20 adults on >= 1 surveys (with caveats). The odds of exuviae occurrence when these conditions were met were similar to 9 to 18x greater than when no adults were detected. Species residency may be accurately inferred during adult surveys, potentially improving freshwater applications and conservation via dragonflies.
The Australian Odonata fauna is reviewed. The state of the current taxonomy and ecology, studies on biodiversity, studies on larvae and the all identification keys are reported. The conservation status of the Australian odonates is evaluated and the endangered species identified. In addition the endemic species, species with unusual biology and species, not threatened yet, but maybe becoming critical in the future are discussed and listed.
Dragonflies are conspicuous insects. Many are large; they fly strongly; most are brightly coloured. As a result, they have been collected extensively. Their larvae are less familiar. 'Mud-eyes', as some are called, are drab, and almost all live in fresh waters, out of sight. They are, perhaps, best known as bait for freshwater fish. The dragonflies constitute a very distinct order of insects, the Odonata. In Australia, two suborders are represented: damselflies (Zygoptera), generally very slender insects, the fore- and hindwings similar in shape and venation and commonly held closed above the body at rest (Figs 46-63), the larvae with external gills on the end of the abdomen (Figs 4A-C, E); and dragonflies proper (Anisoptera), stouter, stronger-flying insects, the fore- and hindwings more or less dissimilar in shape and venation and commonly held spread at rest (Figs 64-101), the larvae with internal, rectal gills (see Chapter 2). Living representatives of the third suborder (Anisozygoptera) are confined to Japan and the Himalayas. The term 'dragonfly' is commonly applied to the entire order.
Zygonix iris is widespread in tropical Asia, and larvae are sprawlers/clingers on rock surfaces in fast-flowing streams and rivers. In the Lam Tsuen River, Hong Kong, this species is univoltine; emergence occurs prior to the summer monsoon and larval recruitment during the wet season. Studies on larval dietary composition in four habitats indicated that Z. iris is a generalist predator, consuming epibenthic prey taxa in proportion to their abundance in the environment. Larval Chironomidae (Diptera) and Baetis (Ephemeroptera) were the commonest food items at all sites and there was little consistent evidence of preference for individual taxa. Larger Z. iris larvae tended to consume more prey taxa than did smaller larvae, and Baetis prey size was positively correlated with predator size. No size selection of chironomid larvae was apparent. Despite its unusual larval habit, Z. iris is a generalist feeder resembling lotic and lentic temperate-zone Odonata.
1. Spatial and temporal changes in larval densities were used to infer patterns of habitat use and survivorship in a fourteen-species assemblage of dragonflies (Odonata: Anisoptera) in a small fishless pond. The density of all species combined peaked at >1000 m−2 in late summer, Most species (e.g. Libellula spp.) were restricted to shallow, nearshore habitats (<1.0m in depth), but a few (e.g. Epitheca spp.) also used deeper areas of the pond. Only Perithemis tenera was most abundant in deep habitats.
2. Because many species exhibited temporal shifts in their use of habitats, it was necessary to estimate survival from changes in population size, calculated as the product of density and habitat area, summed across habitats. In most species, periods of high mortality in autumn and spring were separated by 3–4 months of negligible mortality in winter. Survivorship was linear only in the two species that completed all of larval development in summer (Sympetrum vicinum and Pantala flavescens). Average survival rates for these two species (−0.0049 and −0.0079 log density d−1) were similar to those in previous studies (Lawton, 1970; Benke & Benke, 1975).
3. Survivorship in many species was confounded by other life history phenomena such as (i) mixed voltinism, (ii) overlapping migrant and resident cohorts, and (iii) asynchronous development within species. Asynchrony made it difficult to estimate initial and final population sizes, hence total larval survivorship. However, based on emergence data, only 0.4–3% of larvae survived after peak abundance. None of this mortality can be ascribed to vertebrate predation, and only a little to overwintering stress and starvation. Thus, predation by invertebrates might play a major role in the regulation of these populations.
Euphaea decorata in Tai Po Kau Forest Stream (Hong Kong) was univoltine. Most recruitment took place in summer, and larval growth proceeded throughout the year. Life-cycles recorded in 1977–78 and 1978–79 were similar. Annual production estimates, using the removal-summation, instantaneous growth and size-frequency methods, were more similar for the 1978–79 generation (ranging from 158.7–174.7; mean 1671 mg dry wt m-2) than for the 1977–78 generation (93.9-173-6; mean 131.7 mg dry wt m-2). Mean biomass was similar for both generations (ranging from 33.5–33.9 mg dry wt m-2), and mean P/B ratios were 3.9 1977–78) and 5.0 (1978–79). These are the first estimates of annual production by an Oriental stream insect.
Larvae were most abundant at microsites in the middle of the stream. Multiple regression analysis indicated that substratum characteristics were a major determinant of microdistribution. Euphaea decorata apparently favoured poorly-sorted sediments with highly peaked grain size-frequency distributions, containing few fine particles.
The carnivorous larvae showed ontogenetic changes in diet. Small individuals consumed mainly chironomid (Diptera) larvae; the diet expanded to include (successively) larvae of Ephemeroptera and Trichoptera as E. decorata grew. Seasonal changes in diet were also apparent, although larval diets during spring and summer were similar. There was also considerable overlap between autumn and winter diets. Ontogenetic influences upon prey consumed were not sufficient to account for the observed seasonal differences.
Sampling of larval and adult Odonata from 16 sites along the Kiewa River, Victoria, yielded 34 species: 10 Zygoptera, 24 Anisoptera.
Patterns of larval and adult incidence were appraised, and showed that most species were restricted in incidence to several
consecutive sites along the river, and that there is clear distinction also between the faunas of the potamon, rhithron and
eucrenon regions. Different species of some genera of Anisoptera displayed different zonational distributions, and patterns
of incidence and relative abundance of larvae and adults confirmed zonational occupancy. For larvae, these distribution patterns
transcended the mode of collection, although many species were found most abundantly in one microhabitat or by one of several
sampling methods employed at each site. Sampling of the two stages separately showed considerable concurrence of distributional
patterns, so that either stage alone may provide data of value in faunal and conservation assessment.
The Aus-tralian Dragonflies. A guide to the identification, distributions and habitats of Australian Odonata Spatial distribution, life history and estimates of survivorship in a fourteen-species assemblage of larval drag-onflies (Odonata: Anisoptera)
- J A L Watson
- G Theischinger
- H M Abbey
- Csiro
- Melbourne
- S A Wissinger
Watson J.A.L., Theischinger G. and Abbey H.M. 1991. The Aus-tralian Dragonflies. A guide to the identification, distributions and habitats of Australian Odonata. CSIRO, Melbourne. Wissinger S.A. 1988. Spatial distribution, life history and estimates of survivorship in a fourteen-species assemblage of larval drag-onflies (Odonata: Anisoptera). Freshwater Biology 20: 329– 340.
A survey of threatened dragonfly habitats in cen-tral Europe, especially bogs and bog management Proceedings of the in-ternational symposium on the conservation of dragonflies and their habitats
- E Schmidt
Schmidt E. 1995. A survey of threatened dragonfly habitats in cen-tral Europe, especially bogs and bog management. In: Corbet P.S., Dunkle S.W. and Ububata H. (eds), Proceedings of the in-ternational symposium on the conservation of dragonflies and their habitats. Japan Society for the Preservation of Birds, Kushiro, pp. 45–68.
Dragonfly larvae of the River Murray System. A preliminary guide to the identification of known final instar odonate larvae of south-eastern Australia
- J H Hawking
- J.H. Hawking
Hawking J.H. 1986. Dragonfly larvae of the River Murray System. A preliminary guide to the identification of known final instar odonate larvae of south-eastern Australia. Technical Report No.
Larval dragonfly communities in different habitats of a Mediterranean running water system
- P Schridde
- F Suhling
- P. Schridde
Schridde P. and Suhling F. 1994. Larval dragonfly communities in different habitats of a Mediterranean running water system. Adv. Odonatol 6: 89–100.
A survey of threatened dragonfly habitats in central Europe, especially bogs and bog management
- E Schmidt
- E. Schmidt
Status survey and conservation action plan
- N W Moore
- N.W. Moore