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-The main processes through which invasive species affect amphibians. (a) Examples of direct impacts. (b) Examples of complex impacts, often mediated via interactive effects. (c) Examples of the most frequent taxonomic groups involved in each process. Native species are depicted in blue. Invasive species are depicted in red. Drawings by MF, GFF, B. Comix, and N. Sinegina and obtained from http://www.supercoloring.com/ under a Creative Commons 4.0 License. A color version of this figure is available online.
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The recognition that invasive alien species (IAS) are among the greatest threats to biodiversity has stimulated a growing interest in their impacts on native amphibians. Here we describe the multifaceted consequences of biological invasions on native amphibians and identify potential mechanisms and strategies that could better enable the long-term...
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... can affect amphibians through a broad range of pathways ( Fig. 2; Bucciarelli et al. 2014;Nunes et al. 2019) including predation ( Kats and Ferrer 2003), competition ), hybridization ( Dufresnes et al. 2016), habitat alteration ( Matsuzaki et al. 2009), and the spread of disease ( Miaud et al. ...
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Biological invasions pose significant threats to biodiversity, while impacting ecosystem services, human health, and cultural heritage. Despite these far-ranging effects, their impacts are generally underappreciated by both the public and policymakers, resulting in insufficient management and inadequate conservation outcomes. Recognizing the gap in...
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... The growth of red devil fish species in Lake Batur is quite fast, and it is not a target species for fishers, so the fish are more advanced. Because they prey on native species, invasive species can have an impact (Falaschi et al., 2020) hybridization (Duenas et al., 2021Noella et al., 2021), disease spread (Chalkowski et al., 2018) and competition for available resources (Green and Grosholz, 2021). The natural biodiversity of many countries has been replaced by invading and potentially invasive species (Bax et al., 2003;Franco et al., 2023;Gois et al., 2015;Haubrock et al., 2021;Peh, 2010;Syahroma et al., 2019;Taradipha et al., 2018). ...
Lake Batur is one of the national priorities, as it has economic value, and fish resources are used for food security and improving the local people’s welfare. The study examined the applicability of fisheries management status based on the ecosystem approach in lakes. The study was carried out from February to July 2023 using ecosystem approach methods in seven villages around Batur Lake, Bali, Indonesia, Data was collected through observations and interviews with 189 respondents. The success of fisheries management might be shown as a flag model after the composite domain and the total aggregate value of all dominants were rated. The results showed that the managed fish resources and stakeholders were unsatisfactory categories. Generally, social and fishing technology domains were classified as good categories. For that, ecosystem approach applications for sustainable fisheries in Batur Lake needed action under the five common scenario goals (a) reducing non-target fish (red devil) in the lakes by intensive capture and processing into other products of economic value; (b) regulations related to the reserve area as a place for fish to spawn and breed; (c) increasing the synergy of fisheries management policies; (d) increasing the stakeholder capacity; and (e) government support and related stakeholders regarding one regulation for fisheries management.
... Reptiles also have diverse reproductive and development pathways, from external egg laying to direct development and live birth, although most species occupy specific habitats for their entire lifecycle. Coincident with the alteration of amphibian and reptile habitats are many other threats: invasive species (Gibbons et al. 2000, Pilliod et al. 2012, Falaschi et al. 2020, chemical contamination (Mann et al. 2009, Haas et al. 2018, diseases (James et al. 2015, Burbrink et al. 2017 (Table 1): (1) state laws are at the heart of wildlife policy and management as species are held in the public trust by states; (2) federal laws address broad conservation issues such as endangered species across all states and specific concerns for certain land allocations; (3) private lands adhere to both state and federal authorities but have privacy rules and conservation-agreement options that may affect regulatory implementation; and (4) tribal lands are sovereign nations on which U.S. laws do not apply unless conservation agreements are developed. ...
Wildlife stewardship is of utmost importance in the United States, where management for sustainable natural resources is extended to native species including amphibians and reptiles. The U.S. wildlife conservation framework is a nested system of authorities regulating species and habitats, science-based management and policy decisions, and adaptive management as new knowledge is applied to improve outcomes of population-and habitat management actions. Yet the approach has evolved through time, from single-species management of game species to the conservation of entire ecosystems and the biodiversity they support. Today, the mismatch of conservation ideals with conservation capacity puts nongame species like amphibians and reptiles in the crosshairs for losses due to insufficient resources to address growing numbers of threats. Despite these challenges, optimism prevails, as the management and conservation of U.S. herpetofauna is an increasing priority of the public, with considerable investment into habitat restoration, species-specific threat mitigation, research, public outreach, and education. Herein, we outline key elements of U.S. herpetological conservation efficacy: (1) a web of legal authorities governing the management of U.S. herpetofauna and their habitats; (2) a network of people and organizations that work toward filling priority knowledge gaps by conducting scientific research and that are actively engaged in the science-management interface for species-to-ecosystem level conservation decision-making, and (3) a learning framework of adaptive management within the legal landscape ("lawscape") and for improving effectiveness of conservation actions. Lastly, the human dimension of species conservation in the U.S. is emerging, where bottom-up local efforts are having success in addition to state-and regional-scale approaches. We propose U.S. herpetological conservation priorities under three themes: threats, research, and human dimensions (people). Together these multifaceted efforts are contributing to advances in the maintenance of U.S. amphibian and reptile diversity. The success of these efforts is notable and could be viewed as a model system, where lessons learned may apply elsewhere.
... Variable population sizes induce heterogeneity in site-specific detection probabilities, and species that are more abundant within a site are generally easier to detect (Royle and Nichols 2003). Many amphibian species are vulnerable to predation by fish (Falaschi et al. 2020) that can decrease abundance and local population sizes (Hamer and Parris 2013;Schmidt et al. 2021), sometimes to extinction (Knapp and Matthews 2000). Therefore, the presence of predatory fish species is often an important determinant of amphibian community structure and turnover in freshwater ponds (Snodgrass, Bryan, and Burger 2000;Wellborn, Skelly, and Werner 1996;Werner et al. 2007). ...
Research into freshwater communities often aims to link patterns of species distribution in ponds with underlying biotic factors. However, errors with species detection (e.g. false negatives) may underestimate distribution and bias assessments of community structure. Occupancy models that account for imperfect detection offer a solution to this problem. Here, we used three methods (call/visual encounter surveys, dip‐netting and newt trapping) to survey amphibians and fish (potential amphibian predators) at 100 ponds in an urbanised landscape in Hungary over one breeding season. We estimated species detection probabilities for amphibians (all life stages combined) and fish using occupancy models to gain insight into amphibian‐fish relationships and other survey‐specific variables. We detected nine amphibian and 20 fish species. There were relatively low but variable estimated probabilities of detection for amphibians (mean: 0.320, 95% Bayesian credible interval: 0.142–0.598), with three species having detection rates < 0.1. Probabilities of detection peaked in the middle of the breeding season and increased with survey effort. Detection probabilities of five species were negatively associated with the detection of fish at a pond, while there were positive relationships between detection and emergent vegetation cover. We found no substantial differences in detection rates among the three survey methods. The probability of detecting fish was much higher than for amphibians (0.588, 0.503–0.717) but was lower at ponds with high emergent vegetation where amphibian detection was higher. Our results underscore the importance of accounting for the imperfect detection of both response organisms and potentially interacting species in aquatic community studies. We recommend applying multi‐species occupancy models to enable inference for both common and rare species at ponds in landscapes subjected to human disturbances.
... Particularly amphibians are often more susceptible to these changes due to their permeable skin, and their communities can show significant shifts in taxonomic and functional diversity (Ernst et al. 2006;Ernst and Rödel 2008). In disturbed environments, amphibian and reptile communities are less diverse than in pristine or protected ones mainly due to microhabitat loss, lack of food (Gardner et al. 2007; Trimble and Aarde 2014; Thompson et al. 2015) competition, predation, spread of diseases from invasive species (Bucciarelli et al. 2014;Kraus 2015;Falaschi et al. 2020), in addition to habitat alteration and hybridization (Falaschi et al. 2020). Also, disturbed habitats can lead to significant species turnover at the landscape scale, favoring generalist or invasive species while also sustaining a few native species (Wanger et al. 2010). ...
... Particularly amphibians are often more susceptible to these changes due to their permeable skin, and their communities can show significant shifts in taxonomic and functional diversity (Ernst et al. 2006;Ernst and Rödel 2008). In disturbed environments, amphibian and reptile communities are less diverse than in pristine or protected ones mainly due to microhabitat loss, lack of food (Gardner et al. 2007; Trimble and Aarde 2014; Thompson et al. 2015) competition, predation, spread of diseases from invasive species (Bucciarelli et al. 2014;Kraus 2015;Falaschi et al. 2020), in addition to habitat alteration and hybridization (Falaschi et al. 2020). Also, disturbed habitats can lead to significant species turnover at the landscape scale, favoring generalist or invasive species while also sustaining a few native species (Wanger et al. 2010). ...
In Mexico, land use changes have significantly impacted the diversity of amphibians and reptiles in a negative way. In light of this, we evaluate the alpha and beta components of the taxonomic diversity of amphibians and reptiles in a heterogeneous landscape in west-central Mexico. Additionally, we provide a checklist of amphibian and reptile species recorded over nine years of observations within the studied landscape and surrounding areas. The land cover/use types with the highest species richness and alpha taxonomic diversity differed between amphibians and reptiles. Overall beta taxonomic diversity was high for both groups, but slightly higher in reptiles. This taxonomic differentiation mainly corresponded to a difference in the turnover component and was greater in pristine habitats compared to disturbed ones. The checklist records 20 species of amphibians (ten of which are endemic) and 48 of reptiles (30 endemics). Additionally, the study expands the known geographical distribution range of one species of frog and three species of snakes. Our findings suggest that heterogeneous landscapes with diverse land cover/use types can provide essential habitats for the conservation of amphibian and reptile species.
... Initiative-taking conservation programs should give priority to practical management measures that prioritize prevention, monitoring, and early control as they are the most effective means of mitigating the impacts of IAS. The situation of local populations can be significantly improved by IAS eradications and mitigation strategies, should IAS become established (Falaschi et al., 2020). Since invasive alien species pose a serious threat to local plants, they must be kept out of areas designated for plant conservation, particularly when those species are endangered or endemic. ...
Zoology: Advancements and Research Trends is a comprehensive compilation of cutting-edge research and insights in the field of Zoology. This book has been meticulously curated to serve as an invaluable resource for students, researchers, and professionals who are keen to explore the latest advancements and emerging trends in various sub-disciplines of Zoology, including toxicology, pharmacology, and general zoology. As an Assistant Professor in the Department of Zoology, Wildlife, and Fisheries at the University of Agriculture, Faisalabad, I, Dr. Muhammad Umar Ijaz, have dedicated over a decade to advancing our understanding of animal physiology, cell biology, toxicology and pharmacology. My extensive experience in these fields, coupled with my broader expertise in general zoology, has provided me with a profound appreciation for the complex interplay between living organisms and their environments. This book reflects my commitment to bringing together a diverse array of topics that highlight the breadth and depth of contemporary zoological research. Zoology: Advancements and Research Trends is not just a collection of research topics but a reflection of the collaborative spirit that drives scientific progress. The diverse expertise of the contributing authors ensures that this book offers a well-rounded perspective on the current trends and future directions in Zoology. I hope that this book will serve as a valuable reference for those in academia and industry, providing insights that will inspire future research and contribute to the ongoing dialogue in the field. It is my sincere belief that the knowledge shared within these pages will help shape the future of Zoology, ultimately contributing to the betterment of our understanding and stewardship of the natural world. I would like to express my gratitude to all the contributors, reviewers, and colleagues whose efforts have made this book possible. I also extend my thanks to the students and researchers who continue to push the boundaries of what we know and what we can achieve in this dynamic field.
... Likewise, some invasive and highly traded species such as the bullfrog Lithobates catesbeianus are vectors of emerging diseases such as ranavirus and chytrid fungus (Schloegel et al., 2009). Managing habitats and the invasion pathways that lead to them helps control existing invasions and minimise the risk of new invasions and are thus essential for safeguarding amphibian populations (Falaschi et al., 2020). Furthermore, it is critical to maintain continuity of invasive alien species control operations, particularly steady and reliable funding, to achieve success . ...
Habitat loss is the primary driver of amphibian declines. The protection and management of habitats are thus the most critical conservation actions needed for at least 60% of amphibians, with habitat loss accounting for population declines and extinctions at local and regional levels. Habitat loss is directly related to pollution, but it also exacerbates other major threats to amphibians, such as disease, illegal trade, and invasive species. Habitat loss
also reduces the ability of amphibian species to disperse and alter their distribution within their ecophysiological
tolerance ranges in order to adapt to climate change. Currently, less than 30% of amphibian species are represented in the global protected-area system. The restricted geographic distribution, high habitat-specificity, and dependence on narrow climatic envelopes of many amphibian species mean that amphibians are particularly prone to local extinctions. Of the 37 amphibian species reported as extinct as of 2021, 48.6% were distributed in South and Southeast Asia, and 21% in Mesoamerica. These species mainly inhabited inland wetlands and forests. Considerable research into understanding the effects of habitat loss, fragmentation and degradation on amphibians have been undertaken over the past 15 years, including a review on the effectiveness of amphibian-targeted conservation interventions.
Habitat protection and management priorities must include the urgent preservation of remnant native forest habitats,
given that over 85% of amphibian species occur in these systems. Conservation actions must also include the
protection and rehabilitation of other aquatic and terrestrial breeding habitats critical for supporting viable amphibian populations. Given the limited resources for conservation, protection of globally important sites for amphibians (such as Alliance for Zero Extinction- AZE, and Key Biodiversity Areas - KBA), and their integration with protected areas into a network of conservation areas, is a key priority. The creation, rehabilitation and restoration of amphibian habitats, including in urban and agricultural landscapes, must not be excluded from the toolkit of interventions needed to avoid declines of more generalist species. Beyond implementing direct habitat protection mechanisms, it is essential to ensure targeted management of newly created protected areas and improve that of existing protected areas, inclusive of amphibians. For these actions to be sustainable, it is critical to facilitate the participation, communication, and involvement of a broad range of stakeholders, including government entities, productiveextractive sectors, NGOs, academia, local communities, and civil society.
... Alien species were found to influence amphibian fitness, population size and community structure via predation and competition. The amphibians respond by modulating aspects of their behaviour, morphology, or life history [58]. In the presence of alien species amphibian activity was found to be significantly higher while amphibian development time was found to be significantly shorter. ...
Amphibians are small cold blooded tetra pods containing frogs, toads, caecilians and salamanders. There are over 8,500 species of amphibians known all over the world and nearly 447 species from India inhabiting water habitats. The International Union for Conservation of Nature (IUCN)'s Red List of threatened species estimates that at least one-third of known amphibian species are threatened with extinction, a rate much higher than that for other vertebrate groups like birds and mammals. Amphibian population decline represent a leading example of biodiversity crisis as they are continuously disappearing from their habitats on a global scale. Factors responsible for the amphibian decline are numerous and complex likes habitat destruction, alien species invasive, over exploitation, climate change, infectious diseases and chemical contamination. Amphibians are the crucial component of the ecosystem so their conservation becomes the need of hour. The conservation priority should include the population monitoring and environment sensing, reservation of wetlands, reservoirs, ponds, habitat restoration and management, minimizing the use of pesticides, captive breeding program for endangered species and also awareness among local people about the importance of frogs and toads.
... Freshwater ecosystems suffer extinction rates considerably higher than those of marine or terrestrial ecosystems (Sala et al., 2000;Reid et al., 2019) and amphibians, which larval stages usually inhabit fresh waters, are particularly vulnerable to extinction (Wake & Vredenburg, 2008;Collins, 2010;Luedtke et al., 2023;Stark & Schwarz, 2024). Among the multiple causes of such extinction are emergent infectious diseases (Scheele et al., 2019;Fisher & Garner, 2020), invasive species (Falaschi et al., 2020), climate change (Blaustein et al., 2010), overexploitation (Bishop et al., 2012), habitat loss and fragmentation (Becker et al., 2007;Gallant et al., 2007) and pollution (Blaustein et al., 2003). However, surprisingly, the effects of the loss of amphibian species on the functioning and structure of freshwater ecosystems are still poorly known (Ranvestel et al., 2004;Whiles et al., 2006Whiles et al., , 2013. ...
Amphibians are among the most endangered taxa worldwide, but little is known about how their disappearance can alter the functioning and structure of freshwater ecosystems, where they live as larval stages. This is particularly true for urodeles, which often are key predators in these ecosystems. The fire salamander (Salamandra salamandra) is a common predator in European fresh waters, but the species is declining due to habitat loss and the infection by fungal pathogens. We studied the consequences of fire salamander loss from three montane streams, by comparing two key ecosystem processes (periphyton accrual and leaf litter decomposition) and the structure of three communities (periphytic algae, aquatic hyphomycetes and invertebrates) using stream enclosures with and without salamander larvae. Salamander loss did not cause changes in invertebrate abundance or community structure, except for one stream where abundance increased in the absence of salamander larvae. However, salamander loss led to lower periphyton accrual, changes in algal community structure and slower leaf litter decomposition, with no associated changes in fungal communities or microbial decomposition. The changes observed may have been caused by release of salamander predatory pressure on invertebrates, which could have promoted their grazing on periphyton, in contrast to their preference for leaf shredding in the presence of salamander. Our study demonstrates an important role of salamander larvae in montane streams through top‐down control of lower trophic levels and thus in regulating key stream ecosystem processes. Our results highlight the need for improving protection measures for amphibians to prevent these alterations on ecosystem structure and function.
... Alterations in the availability of ponds and hydroperiod shortening can also induce developmental acceleration in amphibians, with concomitant consequences for postmetamorphic survivorship, time to sexual maturity and dispersal rates (Burraco, Díaz-Paniagua, et al., 2017;Burraco, Valdés, et al., 2017;Cayuela, Arsovski, Thirion, et al., 2016;Cayuela, Boualit, Arsovski, et al., 2016;Liedtke et al., 2021). On the other hand, non-native fish and crayfish, which have been introduced in wetlands worldwide, exert strong predation pressure on amphibian eggs and tadpoles, often causing local population extinctions (Cruz et al., 2008;Díaz-Paniagua et al., 2014;Falaschi et al., 2020). Unlike other recognised causes of amphibian declines (e.g. ...
... Furthermore, strongly aquatic and ecologically resilient species such as P. perezi and P. waltl may indirectly benefit from reduced competition with other amphibians, especially at larval stages, which might be more severely affected by both invasive species (Ficetola et al., 2011). Nevertheless, both red swamp crayfish and mosquitofish pose serious threats to amphibians (Cabrera-Guzmán et al., 2017;Falaschi et al., 2020;Hamer et al., 2002;Kats & Ferrer, 2003), and red swamp crayfish in particular have been directly responsible for local extinction of amphibian guilds in other regions (Cruz et al., 2008;Cruz & Rebelo, 2005;Ficetola et al., 2011), so their overall negative impact on amphibian communities should not be overlooked, even when no clear signs of genetic impoverishment are yet evident. ...
Wetland ecosystems worldwide are threatened by habitat alteration, climate change and the introduction of invasive species, even within protected areas. Unravelling the reliance of sensitive wetland‐dwelling species, such as amphibians, on habitat characteristics is thus essential to identify conservation targets.
Here we assess the distribution of genetic diversity of two strongly aquatic amphibians ( Pelophylax perezi and Pleurodeles waltl ) in association with habitat features across the most extensive, protected wetland of the Iberian Peninsula: Doñana National Park.
Despite inhabiting a protected area free from anthropogenic barriers, the genetic diversity of P. perezi and P. waltl is not homogeneously distributed across the wetland, but instead concentrates in core areas, mainly in the northern zone. Both genetic diversity and connectivity (as opposed to genetic differentiation) showed significant positive associations with the area of the breeding sites and the flooded area surrounding the breeding sites within the dispersal potential of either species, that is nearby pond availability.
Large water bodies connected to abundant temporary ponds are key for the maintenance of amphibian genetic diversity. Nevertheless, the core populations of our target species, which show markedly aquatic habits, are concentrated in areas colonised by invasive species, which could compromise their long‐term viability.
Our results highlight that maintaining widely connected arrays of ponds of different hydroperiods, including large breeding sites free from invasive predators and competitors, is paramount for amphibian conservation in Mediterranean wetlands.
... Short-term observations may suggest positive, negative, or flat trends, leading to potentially misleading conclusions about the species' population dynamics. The inclusion of as many years as possible in time series is therefore crucial, as only coherent longterm data can reveal the true trajectory of dynamic non-native populations considering the background community context(Falaschi et al., 2020;Strayer et al., 2017). ...
Biological invasions pose a rapidly expanding threat to the persistence, functioning, and service provisioning of ecosystems globally, and to socio-economic interests. The stages of successful invasions progress driven by the same mechanism that underlies adaptive changes across species in general—via natural selection on intraspecific variation in traits that influence survival and reproductive performance (i.e., fitness). Surprisingly, however, the rapid progress in the field of invasion science has resulted in a predominance of species-level approaches (such as deny lists), often irrespective of natural selection theory, local adaptation and other population-level processes that govern successful invasions. To address these issues, we analyse non-native species dynamics at the population level by employing a database of European freshwater macroinvertebrate time series to investigate spreading speed, abundance dynamics, and impact assessments among populations. Our findings reveal substantial variability in spreading speed and abundance trends within and between macroinvertebrate species across biogeographic regions, indicating that levels of invasiveness and impact differ markedly. Discrepancies and inconsistencies among species-level risk screenings and real population-level data were also identified, highlighting the inherent challenges in accurately assessing population-level effects through species-level assessments. In recognition of the importance of population-level assessments, we urge a shift in invasive species management frameworks, which should account for the dynamics of different populations and their environmental context. Adopting an adaptive, region-specific, and population-focused approach is imperative, considering the diverse ecological contexts and varying degrees of susceptibility. Such an approach could improve and refine risk assessments while promoting mechanistic understandings of risks and impacts, thereby enabling the development of more effective conservation and management strategies.