Thermal conditions predict intraspecific variation in senescence rate in frogs and toads

Variation in temperature is known to influence mortality patterns in ectotherms. Even though a few experimental studies on model organisms have reported a positive relationship between temperature and actuarial senescence (i.e., the increase in mortality risk with age), how variation in climate influences the senescence rate across the range of a species is still poorly understood in free-ranging animals. We filled this knowledge gap by investigating the relationships linking senescence rate, adult lifespan, and climatic conditions using long-term capture–recapture data from multiple amphibian populations. We considered two pairs of related anuran species from the Ranidae (Rana luteiventris and Rana temporaria) and Bufonidae (Anaxyrus boreas and Bufo bufo) families, which diverged more than 100 Mya and are broadly distributed in North America and Europe. Senescence rates were positively associated with mean annual temperature in all species. In addition, lifespan was negatively correlated with mean annual temperature in all species except A. boreas. In both R. luteiventris and A. boreas, mean annual precipitation and human environmental footprint both had negligible effects on senescence rates or lifespans. Overall, our findings demonstrate the critical influence of thermal conditions on mortality patterns across anuran species from temperate regions. In the current context of further global temperature increases predicted by Intergovernmental Panel on Climate Change scenarios, a widespread acceleration of aging in amphibians is expected to occur in the decades to come, which might threaten even more seriously the viability of populations and exacerbate global decline.

Demonstration of subsurface passive acoustic monitoring (SPAM) to survey for and estimate populations of imperiled underwater-calling frogs

The management and recovery of threatened and endangered amphibians on Department of Defense (DoD) lands relies on an understanding of their distribution and abundance. Fortunately, most anuran species can be surveyed acoustically using vocalizations during the breeding season. This work demonstrated the use of subsurface passive acoustic monitoring (SPAM) to survey for rare underwater-calling, at-risk anuran species on DoD installations. We evaluated the performance of SPAM relative to traditional passive acoustic monitoring (PAM) (microphone) and human manual calling survey (MCS) methods. Results showed that SPAM outperformed PAM and MCS in validation experiments where calls were generated underwater; SPAM was less successful than PAM and MCS in the field demonstration. Most leopard frog calls were apparently produced in air despite previous reports of extensive underwater-calling behavior. This project highlights how acoustic information can help address a data gap in the ecology of at-risk species, which can help refine future survey methodology and management efforts. Ultimately, the utility of SPAM for underwater-calling species will depend on the focal species, the landscape where it occurs, and technological considerations available to the surveyor. SPAM is more expensive than traditional methods but, in some situations, may be the only way to effectively detect species.

Giant pelobatid fossil larva from the middle Miocene of Bulgaria

So far, in Bulgaria several fossils of extinct anuran species have been found, but all seem doubtful. Only two pelobatid remains have been found from the Balkans and the regions - younger species (Late Pleistocene) of the genus Pelobates from Serbia and Miocene Pelobates sp. from Turkey. The fossil in the current study represents a larva of the genus Eopelobates, the first discovery of this genus not only for Bulgaria but for the Balkans as well. This pelobatid larva is gigantic, more than 200 mm in total length. The fossil is found in a diatomitian complex from the middle Miocene.

Application of eDNA Metabarcoding for Detecting Anura on a Tropical Island

As anuran biodiversity quickly declines, it is important to understand local patterns of anuran occurrence. However, the limitations of traditional sampling methods make anuran biodiversity surveys inadequate. Tropical environments are rich in anuran species, which makes biodiversity measurements more difficult. Therefore, it is important to develop a rapid, inexpensive and nondestructive method to measure anuran biodiversity in tropical environments. We used eDNA metabarcoding to measure anuran diversity at 288 sites in 18 regions of Hainan Island. We also used traditional methods and compared the results with those obtained through the eDNA metabarcoding methods. We detected 9 anuran species by traditional sampling methods. We produced 626 million reads by eDNA metabarcoding and assigned them to 15 anuran species. Therefore, eDNA metabarcoding can be used for rapid and large-scale anuran biodiversity surveys.

The Role of Community Reserved Forests in the Conservation of Anuran Amphibians in Meghalaya, North-East India

The state of Meghalaya is situated in the north-eastern India and it comprises three major regions, namely, the Khasi Hills, the Jaintia Hills and the Garo Hills inhabited by three main tribal groups, the Khasis, the Jaintias and the Garos respectively. The tribal communities of Meghalaya protect and nurture the forests located close to their habitation and consider them as sacred. These Community reserved forests are managed by the community for their benefits and they comprise almost about 90% of the total forest cover in Meghalaya. With the recent trends of development and construction in the state many habitats are getting destroyed at an alarming rate. These community reserve forests have been seen to provide the maximum number of existing and stable habitats for many amphibian (anuran) species. In addition, they served as suitable sites for the breeding activities and oviposition by anurans. Discovery of many new anuran species have also been reported from such reserved forests.

Identification key for anuran amphibians in a protected area in the northeastern Atlantic Forest

The identification of anuran amphibians is still a challenge in megadiverse assemblages. In the Neotropics, the Atlantic Forest harbors more than 600 anuran species, and many studies in this ecoregion report anuran assemblages surpassing 30 species. Taxonomic keys facilitate the identification of biological diversity, however only a few are available for anuran assemblages in the Atlantic Forest. Herein we present an identification key for 40 anuran species distributed across 20 genera and nine families, occurring in the Environmental Protection Area of Catolé and Fernão Velho, northeastern Atlantic Forest. Thirty-five morphological characteristics were used in the key, all of which can be easily observed in living and museum specimens. This pioneer study provides the first identification key for an amphibian assemblage in the northeastern Atlantic Forest and this baseline information acts as the starting point for the development of evolutionary and ecological research in this conservation unit.