Project

Inventories and distributional data on the biodiversity of Sri Lanka

Goal: Here I collate various biodiversity inventorying expeditions conducted in various corners of Sri Lanka together with short communications on opportunistic distributional records of interesting species.

Date: 1 January 2000

Updates
0 new
1
Recommendations
0 new
0
Followers
0 new
33
Reads
0 new
350

Project log

Sandun J. Perera
added a research item
Belihuloya situated in a biogeographical transition zone in south-central Sri Lanka is being threatened by land-use changes. Establishing baseline biodiversity knowledge of an indicator taxa within this lesser explored area, the present study systematically assessed Odonates fauna in different habitat types through a transect survey supplemented with incidental observations. Further, the morphology of larvae and exuvia of some Odonates were opportunistically documented from selected water bodies. Transect survey and opportunistic observations identified 36 species of Odonates (22 dragonflies and 14 damselflies) representing ten families, with ten Sri Lankan endemics. Four species of dragonflies and eight damselflies are nationally threatened, including critically endangered Elattoneura centralis and endangered Libellago greeni. The calculated species richness (R), Shannon-Wiener diversity (H’), evenness (E) and Simpson’s diversity (1/D) values were, 3.51, 2.40, 0.85 &7.90, and 2.85, 2.36, 0.92 & 8.68 respectively for dragonflies and damselflies, while two groups show vertical niche segregation. Low Odonate community similarity coefficients among habitat types indicate they are complementary for conservation planning. Out of ten Odonate species for which larval stages were recorded, the larval morphology of Anax indicus and Gynacantha dravida are described for the first time in Sri Lanka. Baseline data herein are used for evidence-based conservation recommendations.
Pradeep Samarawickrama
added a research item
The Sinharaja Forest Reserve is located in the Southern as well as Sabaragamuwa provinces in the wet zone, between latitudes 6 o 21-6 o 26 N and longitudes 80 o 21-80 o 34 E is one of the biologically unique Tropical Forest in Sri Lanka. Although Sinharaja is considered a lowland rain forest, the Eastern part of the forest consists montane and sub-montane forests. Many scholars have already researched on reptiles in the lowland rain forests of Sri Lanka including Sinharaja, however, they have not significantly attended to the diversity of reptiles in the Eastern and Southern parts of the Sinharaja forest. Considering this gap, the research focuses on studying diversity of reptiles in diverse lowland rain forests, montane and sub-montane forests in the Southern and Eastern parts of Sinharaja. Giguruwa-Kosmulla and Pitadeniya sites in the Southern part, and Hadpanella and Morningside in the Eastern part are selected as study areas of the research. 16 line transects (as four from each site) and quadrate 16 samples (as four from each site) are used for primary data collecting. Lowland rain forests, montane and sub-montane forests are identified as biologically sensitive habitats of reptiles. High number of native reptile species are recorded in lowland rain forests than in montane and sub-montane forests. 36 reptile species are identified in Southern and Eastern parts of the Sinharaja forest and 19 species of them are endemic to Sri Lanka. Among them, 05 vulnerable species, 04 endangered species, 05 critically endangered species are recorded. Many threats have been found, however, among them issues of bio piracy loss of forest genetic resources and wildlife smuggling, illegal forest utilisation practices, gem mining, illegal forest encroachments and unethical tourism practices are major issues. Thus, state forest department and other responsible authorities must attend to minimize the effects of these negative human impact on these vulnerable areas to protect sensitive reptile species in their habitats in order to conserve their diversity.
Mendis Wickramasinghe
added 2 research items
Fernando, Samantha Suranjan, Wickramasingha, Mendis, Rodirigo, Roshan K. (2007): A new species of endemic frog belonging to genus Nannophrys Günther, 1869 (Anura: Dicroglossinae) from Sri Lanka. Zootaxa 1403: 55-68, DOI: 10.5281/zenodo.175474
Pradeep Samarawickrama
added 2 research items
Abstract The Knuckles Forest Range (KFR) is distinct morphological unit of the central highland of Sri Lanka. A survey was carried out using 10 × 10 m plots in two major habitats, namely Montane forest (MF, >1300 m a.s.l.) and Sub montane (600 – 1300 m a.s.l.) forests (SMF) in the Dothalugala MAB reserve in the Knuckles Forest Range in order to evaluate its herpetofaunal diversity. Distribution and abundance of amphibians and reptiles in their microhabitats were recorded during the study. A total of 30 species in 18 genera in 7 families were encountered during the study. This includes two unidentified amphibians as well. Among herpetofauna endemic and threatened Ceretophora tenenntii (Leaf Nosed Lizard) and Nannophrys marmorata (Kirtisinghe’s Rock Frog) are restricted to KFR. Of these 14 species were amphibians and 16 were reptiles. Comparison of herpetofaunal diversity among two forest habitats showed that SMF habitats supported higher diversity for amphibians. According to Shannon index (HI) amphibian diversity in SMF was 1.05 whereas low diversity was recorded from the MF for amphibians (H’ = 0.40). Shannon evenness for SMF was 0.42 while this value for MF was 0.21 for amphibians. Reptiles also showed a similar pattern of diversity where Shannon Index for MF was 0.5 while the SMF recorded higher value (1.29). Shannon evenness for reptiles in the MF was 0.26 and for the SMF was 0.49. Reasons for high diversity in SMF is mainly due to the availability of number of microhabitats including man modified habitats that are favorable for amphibian and reptiles. Low diversity of MF may be due to canopy opening resulting exposure of the forest floor to high temperature and winds. Due to this reason species loose their habitats and are subjected to predation. Findings of this study could be used baseline information for future research works. Keywords Knuckles forest range; Dothalugala Man and Biosphere Reserve; diversity; diversity indices; montane; sub-montane
Pradeep Samarawickrama
added a research item
The monotypic genus Lankanectes, considered an evolutionary long branch with India's Nyctibatrachus as its sister lineage, is represented by L. corrugatus, a species widely distributed within the wet zone of Sri Lanka up to 1500 m asl, where it inhabits a variety of lotic and lentic habitats. Here, following an integrative taxonomic approach using DNA-based phyloge-nies, morphology, morphometry, and ecological niche models, we describe a new species-Lankanectes pera sp. nov. The new species is distinguished from its sister species mainly by its tuberculated throat and absence of dark patches on venter, throat, manus and pes. The uncorrected genetic distances between the two Lankanectes species for a fragment of the non-coding mitochondrial 16S rRNA gene is 3.5-3.7%. The new species has a very restricted climatic distribution with a total predicted area of only 360 km 2 (vs. 14,120 km 2 for L. corrugatus). Unlike L. corrugatus, which prefers muddy substrates and marshy areas, the new species is observed inhabiting only pristine streams flowing through canopy covered montane forests in the highest reaches of the Knuckles Mountain range. The specialized new species will need immediate conservation attention due to its restricted distribution (montane isolate), specialized habit of inhabiting clear mountain streams, and small population size.
Pradeep Samarawickrama
added 2 research items
The monotypic genus Lankanectes, considered an evolutionary long branch with India’s Nyctibatrachus as its sister lineage, is represented by L. corrugatus, a species widely distributed within the wet zone of Sri Lanka up to 1500 m asl, where it in- habits a variety of lotic and lentic habitats. Here, following an integrative taxonomic approach using DNA-based phyloge- nies, morphology, morphometry, and ecological niche models, we describe a new species—Lankanectes pera sp. nov. The new species is distinguished from its sister species mainly by its tuberculated throat and absence of dark patches on venter, throat, manus and pes. The uncorrected genetic distances between the two Lankanectes species for a fragment of the non- coding mitochondrial 16S rRNA gene is 3.5–3.7%. The new species has a very restricted climatic distribution with a total predicted area of only 360 km2 (vs. 14,120 km2 for L. corrugatus). Unlike L. corrugatus, which prefers muddy substrates and marshy areas, the new species is observed inhabiting only pristine streams flowing through canopy covered montane forests in the highest reaches of the Knuckles Mountain range. The specialized new species will need immediate conservation atten- tion due to its restricted distribution (montane isolate), specialized habit of inhabiting clear mountain streams, and small pop- ulation size.
Pradeep Samarawickrama
added a research item
Diversity of Dragonfly Species in the Hakkinda Islands of Mahaweli River in the Gatabe Area Kumara, HIGC 1 & Samarawikrama, VAMPK 1Department of Geography, Faculty of Humanities and Social Sciences. University of Ruhuna Hakkinda Islands surrounded by the Mahaweli River, close to the Kandy-Gatambe area is a bio-geographical hotspot in Sri Lanka, however, bio-geographical importance of these islands has been overlooked during the last few decades as a result of development projects and varied human activities. Considering that, the President of Sri Lanka has made an order declaring the Waratenna-Hakkinda area as a protected environmental area. According to the rudimentary survey, this protected area can be identified a special habitat to dragonfly species, which biologically comes under the ‘insect’ category (order- Odonata & infraorder- Anisoptera). Since the knowledge about diversity of dragonfly species is limited, this research’s main objective is to bridge that gap in prevalent knowledge. This research is guided by Quantitative- Deductive research methodology. Under this methodology, line transects and quadrate sampling methods have been used in primary data collection process. According to research findings, a total of 16 dragonfly species from 08 families are identified and both riverine forest and river islands have rich diversity compared with home gardens in the area. Among the available species, 37.5% are identified to be endemic to the country. Three species, namely, Oriental Green Wing (Neurobasis chinensis), Black-tipped damsel (Vestalis apicalis) and Sri Lanka Ultima gem (Libellago finalis) are identified to be vulnerable species. This research concludes that even if there are a high diversity of dragonfly species in the river islands and riverine forest areas, human activities and their irresponsible behaviour have directly /indirectly negatively influenced on dragonfly habitats and their breeding colonies. The research, thus, identifies an immediate requirement for a mechanism and regulations to protect a biologically important breeding colony of dragonfly species and their habitats to protect their diversity. Key words: Hakkinds protected area, Dragonfly species, Diversity, Habitat protection
D.M.S. Suranjan Karunarathna
added a research item
Terrapins are integral to many freshwater ecosystems, yet are imperilled at a global scale. In Sri Lanka, terrapins are understudied; thus, much of their natural history and distribution status remain unknown. Such paucity of studies impedes conservation. In this study, 79 freshwater habitats located outside the protected area network of south-western Sri Lanka were surveyed to document current population densities and habitat use of two terrapin species: Indian black terrapin (Melanochelys trijuga thermalis) and flap-shelled terrapin (Lissemys ceylonensis). Local inhabitants were interviewed to assess human threats towards terrapins. Both species were recorded in low densities: 1-2 individuals ha⁻¹. Indian black terrapin was found in half of the surveyed sites while flap-shelled terrapin occurred in one-third of the surveyed sites. Highly urbanized river basins had the lowest densities for both species while rural basins supported higher numbers. Basking was the predominant behaviour of both species and large woody debris and boulders were preferred as basking substrates, together with sparse-canopy aquatic habitats with intact marshlands. Overharvesting for meat was a major threat for terrapins. Most local inhabitants were unaware of legislation on terrapin conservation and the ecological importance of terrapins. Human threats such as pollution, modification of aquatic and wetland habitats, and loss of riparian forests were frequently observed in surveyed sites. Terrapin populations outside the protected area are at risk as evidenced by lower population densities and a multitude of human threats. A landscape-scale ecosystem-based conservation approach is recommended for Sri Lanka's terrapins with incorporation of lands with different management regimes (privately owned, municipality managed) into the protected area network. Current environmental legislation should be revised to support buffer zone delineation for aquatic habitats, wetland restoration, and landscape-scale connectivity.
D.M.S. Suranjan Karunarathna
added an update
Mendis Wickramasinghe
added 2 research items
Pseudophilautus hypomelas (Günther, 1876), was previously known from the type collection of 14 specimens deposited in the Natural History Museum, London. There has been no record of this species since the original description by Günther in 1876, and subsequently this species was considered extinct. In recent explorations however, the species has been rediscovered from the Peak Wilderness, Central Hills of Sri Lanka, with a rediscription of the species from fresh collections.
Eight new species of Pseudophilautus (Pseudophilautus bambaradeniyai, P. dayawansai, P. jagathgunawardanai, P. karunarathnai, P. newtonjayawardanei, P. puranappu, P. samarakoon, and P. sirilwijesundarai) were discovered as a result of a survey carried out to study the herpetofaunal diversity with the changes in elevation in the Sripada World Heritage Site (Peak Wilderness), Central Hills of Sri Lanka. Detailed descriptions of new species along with colour photographs and line drawings for each species are provided herein. The new species possess unique morphological characters and are well distinguishable from one another that could be easily identified in the field. The conservation status of all species described here, have been considered Critically Endangered, except for P. newtonjayawardanei, as all the new species are recorded from single locations, and their habitats are under severe threat.
Sandun J. Perera
added a research item
The Wilpattu National Park (WNP) is the oldest and largest national park in the country. It was declared as a sanctuary in 1905 and thereafter upgraded to a national park on February 25, 1938. However, as a result of the civil conflict, the WNP was closed from December 1988 until March 2003. WNP is not only siginificant from an ecological standpoint but is also extremely rich in archaeological terms housing a number of ruins and artefacts dating back to various periods of history. The proximity to the ancient city of Anuradhapura has also been a factor contributing to the rich archaeological heritage of the area. In this context, this pioneering effort in preparing a comprehensive resource inventory for the WNP involved documenting ecological resources, hydrological resources, socio-economic aspects and the archaeological resources of the National Park. The systematic inventorying would further facilitate the development of integrated management plans for the conservation and management of the WNP.
Sandun J. Perera
added a research item
A preliminary avifaunal survey was conducted at Hapugastenne Tea Estate, Ratnapura, Sri Lanka from October to December 2015 with objectives of assessing the bird diversity within different habitats and documenting threats to biodiversity. Bird populations were sampled in 39 line transects and 17 point counts (respectively for terrestrial and aquatic habitats) representing eight habitat strata (tea fields, home gardens, scrublands, secondary forests, natural forests, stream-side vegetation, riverine forests, and water-logged areas) within the estate, replicated in its nine divisions. Transects were conducted during the morning between 07:00 and 09:00 hrs. A total of 91 species, including nine Sri Lankan endemics and nine winter visitors were recorded, which included three nationally threatened (two endangered and one vulnerable) and six near threatened species.
Mendis Wickramasinghe
added 3 research items
A new species of Dendrelaphis, Dendrelaphis sinharajensis sp. nov. is described, the sixth species of the genus known from Sri Lanka. The new species is readily distinguished from all other congeners by its colour pattern and scalation. The species is a canopy-dweller known only from the Sinharaja World Heritage Site and its vicinity, in the lowland wet zone of Sri Lanka.
A new species of Cnemaspis, Cnemaspis rajakarunai sp. nov. is described and is the fourth rock dwelling species belonging to the genus known from Sri Lanka. The new species is readily distinguished from all other congeners by the following combination of characters: adult snout vent length 36 40 mm; precloacal pores absent, large femoero-precloacal scales 22; femoral pores 7 8, enlarged femoral scales 6; ventral scales 146 186; supralabials (to midorbital position) 7; supralabials (to angle of jaws) 9; total lamellae on finger IV 19 22, shape of the basal lamellae on toe IV elliptical; and its unique colour pattern. The new species is recorded from Salgala Forest an unprotected lowland rain forest.
Since the description of the first reptile, Cylindrophis maculate (syn. Anguis maculata) from Sri Lanka by Carl Linnaeus in 1754, large number of reptile species have been recorded from Sri Lanka (Batuwita and Bahir, 2005; Batuwita and Pethiyagoda, 2007; Das, et al. 2008; Deraniyagala 1953 and 1955; de Silva 1980; de Silva 1990; Gans & Fetcho, 1982; Gower and Maduwage 2011; Greer, 1991; Manamendra-Arachchi, et al. 2007; Pethiyagoda & Manamendra-Arachchi, 1998; Smith 1933, 1935 & 1943, Smith et al. 2008; Taylor 1950a, 1950b & 1953, Wall 1921; Wickramasinghe, et al. 2009, Wood et.al., 2012). These published works indicates that Sri Lanka is endowed with a rich reptile fauna. The current list of reptile fauna of Sri Lanka comprise of 211 species of which 59% (124) are considered as endemic species. The reptile fauna can be further categorized in to 103 species of serpentoid reptiles (49 endemic) belonging to 10 families, one Subfamilie and 40 genera (five endemic - Pseudotyphlops, Aspidura, Balanophis, Cercaspis and Haplocercus), and 108 species of tetrapod reptiles (76 endemic) belonging to 12 families with 34 genera (six endemic - Ceratophora, Cophotis, Lyriocephalus, Chalcidoseps, Nessia and Lankascincus).
Sandun J. Perera
added a research item
Thirteen ‘Bird Community Metrics’ and seventy five ‘Bird Species’ were tested for their utility as biological indicators of urbanization pressure and habitat variables, along an urban-suburban gradient in lentic freshwater bodies and their buffer habitats, within the Colombo city and its suburbs. Altogether, 36 point counts were performed in 12 survey stations from the Colombo city centre to its suburbs, and recorded 3997 observations on birds belonging to 75 species. Each survey station was characterized by a combination of seven quantitative and five quantified descriptive variables, concerning the main differences in vegetation and the level of urbanisation. Among the quantitative habitat variables, six cover type variables and the ‘Land Use Index’ were computed using GIS techniques, through satellite image analysis. Detrended Correspondence Analysis of survey stations in ‘Bird Community Metric’ space and ‘Bird Species’ space were performed, taking survey stations vs. ‘Bird Community Metrics’ and survey stations vs. ‘Bird Species’ as the main matrix, and the survey stations vs. ‘Habitat Variables’ as the second matrix respectively. The ordination axes expressing the urbanization pressure were identified through the Pearson’s correlation coefficients of ‘Habitat Variables’ along them. The ‘Indicator Bird Community Metrics’ and ‘Indicator Bird Species’ were identified based on the correlation coefficients of ‘Bird Community Metrics’ and ‘Bird Species’ to those axes (at P<0.05). The results presents enough evidence to statistically accept the research hypothesis; ‘Bird Community Metrics’ and ‘Bird Species’ indicates the urbanization pressure along an urban-suburban gradient in lentic freshwater bodies and their buffer habitats in the Colombo city and suburbs’, for 10 out of 13 ‘Bird Community Metrics’ and 20 out of 75 ‘Bird Species’ respectively (P<0.05). ‘Indicator Bird Community Metrics’; ‘Percentage abundance of three most abundant species’, ‘Percentage richness of tolerant species’, ‘Percentage abundance of tolerant species’, and the ‘Percentage abundance of the opportunistic feeder - House Crow’ were recorded to indicate high urbanization pressure in water bodies and their buffer habitats in Colombo city and suburbs, in addition to six other ‘Indicator Bird Community Metrics’, that indicate sub-urban conditions. In terms of ‘Indicator Bird Species’ the results give statistically significance evidence (P<0.05) to say that, the House Crow indicates urban conditions, while Large-billed Crow and Common Myna indicate sub-urban conditions, within buffer habitats of lentic freshwater bodies in Colombo, in addition to 3 more species to indicate urban conditions, as well as 6 wetland bird species and 8 woodland bird species identified as biological indicators of sub urban conditions. A cluster analysis was performed based on 12 habitat variables as a way of categorizing the survey stations into different steps along the urban-suburban gradient. All identified ‘Indicator Bird Community Metrics’ as well as ‘Indicator Bird Species’ were further confirmed by analyzing their trends along the steps of urban-suburban gradient. In addition, eleven ‘Bird Community Metrics’ have been proven to be successful in the utility as indicators to six specific ‘Habitat Variables’, while nineteen ‘Bird Species’ indicate seven specific ‘Habitat Variables’.
Sandun J. Perera
added 6 research items
A preliminary survey was carried out to investigate the status of animal mortality due to electrocution.The survey was conducted in selected Districts (Colombo, Gampaha, Puttalam, Rathnapura, Galle and Hambanthota), covering all climatic zones of Sri Lanka between December, 2003 to January 2004. Field observations during the above period were supplemented with information gathered from literature, and also through opportunistic observations made prior to the survey in Moneragala and Anuradhapura in addition to the districts mentioned above.The field observations were .made while driving in a vehicle {40-60km/hour) along access roads.Total length of 479 km of electric lines were surveyed during the study period. A total number of 329 specimens of dead animals were recorded and 98.17 % of the specimens belonged to the Flying Fox (Pteropus giganthus). Others included Grey Slender Loris (Loris lydekkerianus), Night Herron (Nycticorax nycticorax) and Village Crow (Corvus macrorhynchos). According to the results 0.69 animals were killed per 1 km distance of electric lines.
We report the first ever observation from Sri Lanka of an Adenomus kelaartii (Kelaart’s Dwarf Toad) being predated and fed upon by a huntsman spider of the genus Heteropoda. The observation was made at 2224 h on 14 March 2015 during dry weather, on a rock outcrop of a fast flowing stream bank in Hunuwela Rubber Estate, Ratnapura District, Sri Lanka (6.6366°N, 80.6005°E, WGS84, 266 m elev.).
A survey was carried out in the Kandakuliya-Kalpitiya SAM area to document the biodiversity associated with this coastal landscape, and identify ecologically sensitive sites. Detailed observations on habitats and species were made over a period of a week, in July 2005. Based on vegetation types, physical conditions and edaphic factors, a total of 10 major habitat types were encountered in the survey area. These included five natural wetland habitat types, three natural terrestrial habitat types and two managed habitat types. The lagoon also sustains patches of sea grass beds, and tidal mudflats, especially around islands. Based on the habitat representativeness, habitat intactness, and richness of species, 16 sites of high ecological significance were identified. The flora recorded from the survey area includes 240 species, under 75 families. These include four endemics and five nationally threatened species. A total of 149 species of vertebrates, and 34 species of butterflies were recorded from the survey area. The vertebrates include one endemic and four nationally threatened species. Poaching, clearance of natural habitats, reclamation of wetlands and spread of invasive alien plants are the main conservation issues in the survey area. Based on the observations made, a set of recommendations are presented to facilitate the conservation of biodiversity in the survey area.
Sandun J. Perera
added 10 research items
The observation of an adult Hoplobatrachus crassus (Jerdon's Bull Frog) swallowing another adult Polypedatus maculatus (Chunam Tree-frog) (Image 1 w) was made at around 2030hr on 2 November 2002 in Kalametiya Wildlife Sanctuary, Sri Lanka. Microhyla ornata (Ornate narrow mouth frog), Limnonectes limnocharis (Common Paddy Field Frog) and Uperodon systoma (Baloon Frog) were also recorded from the same pond during the time of observation.
Sandun J. Perera
added a project goal
Here I collate various biodiversity inventorying expeditions conducted in various corners of Sri Lanka together with short communications on opportunistic distributional records of interesting species.