Endemic Amphibians Research Articles

Genetic variation and differentiation in Indirana beddomii frogs endemic to the Western Ghats biodiversity hotspot

Understanding of biodiversity on a local scale is extremely important for effective conservation measures, especially in biodiversity hotpsots hosting diverse endemic flora and fauna and subject to strong anthropogenic influences. Little is known about patterns of local biodiversity and the processes generating it in the Western Ghats biodiversity hotspot: the patterns of genetic diversity and biogeographic affinities are poorly known for most of the species from this region. We studied the genetic diversity and population structuring of an endemic frog Indirana cf beddomii, from 12 localities of Western Ghats using 15 polymorphic microsatellite loci. The genetic diversity as measured by mean expected heterozygosity (HE = 0.83) or allelic richness (Ar = 10.41) was high and similar in all localities. Significant genetic differentiation (mean FST = 0.075) with a strong pattern of isolation by distance (IBD) across the localities was observed. Clearest genetic discontinuities in the data corresponded to topographic gaps suggesting that apart from IBD, genetic structuring in this species is strongly influenced by habitat matrix. In general, the results provide novel insight into factors that may impact the genetic diversity and population structuring of endemic amphibians in this biodiversity hotspot.

Endemic Amphibians and Their Distribution in China

Endemic Amphibians and Their Distribution in China

Integrating field surveys and remote sensing data to study distribution, habitat use and conservation status of the herpetofauna of the Comoro Islands

We studied the non-marine reptile and amphibian species of the volcanic Comoro archipelago in the Western Indian Ocean, a poorly known island herpetofauna comprising numerous microendemic species of potentially high extinction risk and widespread, non-endemic and often invasive taxa. According to our data, the Comoro islands are inhabited by two amphibian species and at least 28 species of reptiles although ongoing genetic studies and unconfirmed historical records suggest an even higher species diversity. 14 of the 28 currently recognized species of terrestrial reptiles (50%) and the two amphibians are endemic to a single island or to the Comoro archipelago. The majority of species are most abundant at low elevation. However, a few endemic species, like the gekkonid lizards Paroedura sanctijohannis and Phelsuma nigristriata, are more common in or even confined to higher altitudes. We created habitat maps from remotely sensed data in combination with detailed species distribution maps produced using comprehensive data from field surveys between 2000 and 2010, literature, and historical locality records based on specimens in zoological collections. Using these data, we assessed the conservation status of the endemic terrestrial reptiles and amphibians according to the IUCN Red List criteria. Our results show that although little area of natural forest remains on the Comoros, many species are abundant in degraded forest or plantations. Competition and predation by invasive species appears to be the most important threat factor for the endemic herpetofauna, together with habitat degradation and destruction, which further favours invasive species. We propose the status Endangered for three species, Vulnerable for one species, Near Threatened for six species, Least Concern for four and Data Deficient for two species. The endemic subspecies Oplurus cuvieri comorensis is proposed for the status Critically Endangered. Based on the results of this study, seven areas of importance for reptile and amphibian conservation on the Comoros are identified. This study shows how remote sensing data can contribute to increasing accuracy and objectiveness of conservation assessments.

The Effects of Governmental Protected Areas and Social Initiatives for Land Protection on the Conservation of Mexican Amphibians

Traditionally, biodiversity conservation gap analyses have been focused on governmental protected areas (PAs). However, an increasing number of social initiatives in conservation (SICs) are promoting a new perspective for analysis. SICs include all of the efforts that society implements to conserve biodiversity, such as land protection, from private reserves to community zoning plans some of which have generated community-protected areas. This is the first attempt to analyze the status of conservation in Latin America when some of these social initiatives are included. The analyses were focused on amphibians because they are one of the most threatened groups worldwide. Mexico is not an exception, where more than 60% of its amphibians are endemic. We used a niche model approach to map the potential and real geographical distribution (extracting the transformed areas) of the endemic amphibians. Based on remnant distribution, all the species have suffered some degree of loss, but 36 species have lost more than 50% of their potential distribution. For 50 micro-endemic species we could not model their potential distribution range due to the small number of records per species, therefore the analyses were performed using these records directly. We then evaluated the efficiency of the existing set of governmental protected areas and established the contribution of social initiatives (private and community) for land protection for amphibian conservation. We found that most of the species have some proportion of their potential ecological niche distribution protected, but 20% are not protected at all within governmental PAs. 73% of endemic and 26% of micro-endemic amphibians are represented within SICs. However, 30 micro-endemic species are not represented within either governmental PAs or SICs. This study shows how the role of land conservation through social initiatives is therefore becoming a crucial element for an important number of species not protected by governmental PAs.

The Harvest of Endemic Amphibians for Food in Eastern Madagascar

Deliveries of edible, endemic amphibians to a restaurant in eastern Madagascar were monitored over a five-month period in the 2008 austral summer. Each frog collector was interviewed on arrival and information was obtained on collection locality, methods, frequency, as well as recording the number of frogs delivered. A total of 3,233 frogs were delivered to the restaurant during the study, averaging 249 per week. All of the 21 interviews concerned frogs collected in forest habitats at night by teams of between one and three people. Collection occurred in four localities, one of which (Fierenana) necessitated public transport to deliver the frogs. Effort at Fierenana was typically higher than at other sites with collectors frequently spending at least one night in the forest and traveling around 8.3 hours between their homes and forest collection locations. Income generated went directly to the collectors, who always delivered the frogs in person, and supply was determined by their available time, frog abundance, and weather conditions. Although the restaurant had no stated minimum quantity for purchase, small frogs were refused and collectors aimed for a minimum of 60 large frogs per delivery. The income generated by local amphibian collectors at Fierenena was similar for non-threatened edible species destined for domestic consumption (0.29 US$) and the Critically Endangered Mantella milotympanum collected for overseas export (0.32 US$). The harvest of edible frogs provides important income for individual hunters but additional study is needed to investigate its impact on frog populations and to develop methods to link sustainable collection practices with forest management.

Presence of the Chytrid Fungus Batrachochytrium dendrobatidis in Populations of the Critically Endangered Frog Mannophryne olmonae in Tobago, West Indies

The emerging infectious disease chytridiomycosis is prevalent in Central and South America, and has caused catastrophic declines of amphibian populations in the Neotropics. The responsible organism, Batrachochytrium dendrobatidis, has been recorded on three West Indian islands, but the whole of the Caribbean region is predicted to offer a suitable environment for the disease. Monitoring the spread of chytridiomycosis is thus a priority in this region, which has exceptionally high levels of amphibian endemism. PCR analysis of 124 amphibian skin swabs in Tobago (Republic of Trinidad and Tobago) demonstrated the presence of B. dendrobatidis in three widely separated populations of the frog Mannophryne olmonae, which is listed as Critically Endangered on the basis of recent population declines. Chytridiomycosis is presently endemic in this species, with a prevalence of about 20% and no associated clinical disease. Increased susceptibility to chytridiomycosis from climate change is unlikely in amphibian populations in Tobago, as this island does not have high montane environments, but remains a possibility in the sister island of Trinidad. Preventing the spread of chytridiomycosis within and between these and other Caribbean islands should be a major goal of practical conservation measures for amphibians in the region.

Spermatogenesis in Cuban endemic amphibians

Spermatogenesis in Cuban endemic amphibians

WITHDRAWN: Spermatogenesis in Cuban Endemic Amphibians

WITHDRAWN: Spermatogenesis in Cuban Endemic Amphibians

Is the decline of birds and amphibians in a steppe lake of northern Patagonia a consequence of limnological changes following fish introduction?

1. Laguna Blanca, in Laguna Blanca National Park, is a lake in Patagonia which has been designated as a Ramsar site since 1971 because of bird diversity and abundance and importance for nesting, particularly for the black neck swan, Cygnus melanocoryphus. It is also valued for its populations of endemic amphibians, Atelognathus patagonicus and Atelognathus praebasalticus. 2. Avian and amphibian populations have decreased dramatically in recent years. Percichthys colhuapiensis, Percichthys trucha (Pisces, Percichthyidae), Salmo trutta and Oncorhynchus mykiss (Pisces, Salmonidae) were introduced into Laguna Blanca in 1965. Since 1986, no Atelognathus frogs have been found. The abundance of swans and coots, which are strongly associated with macrophytes for nesting and feeding, has diminished drastically, whereas piscivorous birds have increased. 3. The fishless condition of some neighbouring small lakes with abundant pond weeds, aquatic birds and endemic amphibians, was assessed in order to compare the physical and chemical characteristics and the quantitative composition of the benthos among lakes. Fish presence at Laguna Blanca and its absence at El Burro, Antiñir and Jabón lakes, were confirmed. Compared with previous results, it seems that the abundance of Amphipoda (Hyalella), Copepoda and Cladocera at Laguna Blanca has decreased, while Acari has increased and Notostraca has disappeared. Water transparency has diminished in Laguna Blanca and now is lower than that of fishless lakes. 4. P. colhuapiensis were captured only in Laguna Blanca, with the highest captures in the littoral zone. The population shows rapid individual growth in the early years and an absence of fish older than 6 years. The preponderance of benthos and the presence of macrophytes in the gut contents of adult P. colhuapiensis appear to indicate that they are important consumers of these resources. 5. This paper concludes that fish introduction in Laguna Blanca led to a complex trophic cascade effect (fish predation on tadpoles, fish competition for avian food, bottom disturbance, zooplankton reduction) producing deleterious effects on the amphibian and bird populations. Copyright © 2006 John Wiley & Sons, Ltd.

Current status of the threatened amphibians and reptiles of Japan

AbstractThis article compares amphibian and reptile components of the original and revised versions of the Red List of Japan, and analyzes geographic patterns of, and major threats to, species and subspecies now assigned to the threatened categories. The numbers of both amphibians and reptiles categorized as threatened in the Red List of Japan have increased greatly through its revision as a result of recent progress in the taxonomy of these groups in Japan, the introduction of new criteria for risk assessment, and unexpectedly rapid declines in the status of several taxa. Threatened taxa of amphibians and reptiles in the revised list tend to be concentrated in the Ryukyu Archipelago, where deforestation seems to be the major ultimate cause of declines. Reduction in the quality and quantity of inland water environments seems to be the major cause of declines in several endemic amphibians from the main islands of Japan. The importance of conservation was emphasized in the revised list by progress in taxonomy, by new insights and data on the estimation of temporal dynamics of population density or habitat size for threatened taxa, and by the impacts of and need to prevent further deforestation in the Ryukyus and of the ongoing destruction of inland water habitats on the main islands of Japan.

Biogeographical regions of the Iberian peninsula based on freshwater fish and amphibian distributions

We classified the main Iberian river basins based on the presence and absence of freshwater fishes and amphibians. For both taxonomic groups we analysed three data sets; 1) endemic species only, to search for biotic boundaries related to historical events, 2) indigenous species, which include endemic ones, to search for biotic boundaries related to ecological factors, 3) indigenous and well‐established introduced species, to assess the influence of man in the current biogeographical patterns of fishes and amphibians. We used both phenetic and cladistic methods, followed by a consensus analysis to provide an overall biogeographical pattern. Based on all fish distributions, the Iberian Peninsula is divided into three biogeographical regions: Cantabrian, Atlantic and Mediterranean, No boundary existed between the Cantabrian and Atlantic regions when only indigenous fish species were considered. This suggests that this boundary has been induced by man, probably through the differential introduction of fish species into reservoirs at one or other side of the boundary. Run‐off and the size of the river basins are the environmental factors that distinguished the Atlantic and Mediterranean regions. However, regionalization based only on endemic freshwater fishes showed a latitudinal pattern that agrees with the paleogeographic events of the Upper Oligocene‐Lower Miocene period. By contrast, one northern and one southern region were distinguished based on all amphibian distributions and on indigenous amphibians only, which suggests that human activity has not significantly affected the overall biogeographical pattern of amphibians in the Iberian Peninsula. Interannual predictability of precipitation best accounts for this regionalization. Based on endemic amphibians, the Iberian Peninsula is divided into three regions that closely resemble the three separate land areas of the Upper Eocene‐Lower Oligocene period. The consensus between the biogeographical regions based on fishes and amphibians yields five pairs of basins. Geological origin of the basins seems to better explain the consensus between the biogeographical patterns of fishes and amphibians, whereas ecological factors probably contribute to the differences between them.

Endemic Amphibians of India

Endemic Amphibians of India