The Herpetological Journal

https://doi.org/10.33256/hj30.3.118125

pp. 118-125

Authors: Amruta M. Joshi, Edward J. Narayan & Narahari P. Gramapurohit

Abstract: Glucocorticoids (GCs) are primarily involved in mobilising energy reserves to various physiological processes including reproduction. During situations of stress, GCs also help in coping with stress by diverting energy away from processes such as growth and reproduction. Hence, studying annual and seasonal changes in GCs of wild populations can help in understanding their role in stress management and reproduction. The quantification of GCs in wild animals involves capturing, handling and restraining, which could be stressful. Moreover, different species may exhibit differential sensitivity to different stressors. Hence, determining species-specific sensitivities and responses to different stressors may help in developing effective conservation measures. In this context, we studied the annual and seasonal variations in corticosterone metabolites of the Bombay night frog, Nyctibatrachus humayuni. In addition, the effects of handling, marking and short-term captivity (24 h) on corticosterone metabolite levels of N. humayuni were determined. Our results show that urinary corticosterone metabolites (UCM) varied significantly annually and between the sexes; in males, the levels were highest during the breeding season, whilst in females, the levels were highest just before the breeding season. Interestingly, UCM levels of both the sexes were not affected by tagging with visual implant elastomer (VIE), and by short-term captivity, suggesting that these manipulations were not stressful in terms of corticosterone responses.

Keywords: Nyctibatrachus humayuni, glucocorticoids, sex-specificity, short-term captivity, tagging

https://doi.org/10.33256/hj30.3.126134

pp.126-134

Authors: Ulrich Sinsch, Fabienne Leus, Marlene Sonntag & Alena Marcella Hantzschmann

Abstract: Metamorphs of the yellow-bellied toad, Bombina variegata, vary widely in size at metamorphosis in the field. We performed a replicated outdoor mesocosm study to simulate the environmental factor combinations in permanent and ephemeral breeding sites and to quantify their effects on tadpole development (duration of the larval period, metamorph size and body condition). Looking for potential carry-over effects of the larval environment, we quantified locomotor performance of all metamorph phenotypes originating from the mesocosms immediately after metamorphosis under controlled conditions. In contrast to the prediction of life-history theory, tadpoles were unable to adjust developmental rate to water availability, but metamorphs originating from the ephemeral pond treatment were smaller and had a lower body condition than those from the permanent pond treatment. Size-dependent carry-over effects included the length of the first jump following tactile stimulation, burst performance (total length of spontaneous jumps) and endurance (total distance covered in 10 forced jumps). A size-independent effect of larval environment was the prolonged locomotor effort to escape (5.7 consecutive jumps following initial stimulus) of metamorphs from the ephemeral pond treatment compared to same-sized ones (3.7 jumps) from the permanent pond treatment. Thus, we demonstrate that carry-over effects of larval environment on metamorph phenotype and behaviour cause a considerable variation in fitness in the early terrestrial stage of B. variegata. Informed conservation management of endangered populations in the northern range should therefore include the provision of small permanent breeding ponds promoting larger and fitter metamorphs.

Keywords: complex life cycles, mesocosm, plasticity of metamorph phenotype, post-metamorphic jumping performance, delayed density dependence, delayed life-history effects

Ref: https://doi.org/10.33256/hj30.3.126134

Authors: Ulrich Sinsch, Fabienne Leus, Marlene Sonntag & Alena Marcella Hantzschmann

https://doi.org/10.33256/hj30.3.135146

pp.135-146

Authors: Lutz Dalbeck, Monika Hachtel & Róisín Campbell-Palmer

Abstract: Once widespread throughout Eurasia and hunted nearly to extinction, the Eurasian beaver Castor fiber has returned to large parts of its former range, largely through active conservation measures. Beavers can substantially alter small, low order streams and their floodplains through dam construction, burrowing activities and tree felling. Therefore, it is presumed they can significantly influence amphibian distributions, species richness and numbers. We undertook a literature review to compare the available data addressing the effects of beaver dams on amphibians in streams of central temperate and boreal Europe. All 19 amphibian species occurring in the study region were found in beaver ponds, despite their distinctly different habitat requirements. Amphibian species acting as pioneers / early colonisers were under-represented in beaver ponds compared to typical forest species. Open country and ubiquitous species showed intermediate patterns. Beaver ponds in headwater streams often supported the entire spectrum of species occurring in the surrounding landscape, and species numbers in beaver modified headwater streams were comparable to those in floodplains of larger natural rivers. In small headwater streams, beavers tended to be the primary providers of essential habitat for amphibians. In contrast, beaver ponds in the floodplains of larger rivers appeared to have less effect and supported lower average species numbers compared to beaver ponds in headwater streams. We propose that beavers and their habitat creating activities are pivotal determinants of amphibian species richness in the headwater streams, which account for 60–80 % of the water bodies in catchment areas in temperate Europe. By creating habitat for endangered amphibian species, beavers and their ability to modify habitats offer extensive opportunities to implement many aspects of the European Water Framework Directive across the continent and to restore amphibian habitats, contributing to their long-term conservation.

Keywords: natural floodplains, wetland restoration, amphibian habitat, ecosystem engineers, species richness, headwater stream, Anura, Urodela

Ref: https://doi.org/10.33256/hj30.3.135146

Authors: Lutz Dalbeck, Monika Hachtel & Róisín Campbell-Palmer

https://doi.org/10.33256/hj30.3.147158

pp. 147-158

Authors: Giacomo Bruni, Ivan Mirabella, Dario Domeneghetti, Mauro Fasola & Adriana Bellati

Abstract: The introduction of alien water frogs is perhaps one of the most underestimated herpetological conservation issues in Europe. The identification of distinct species is highly challenging at the phenotypic level, and artificial syntopy between various taxa and lineages may lead to diverse outcomes, including hybridisation and local extinction. In central Italy the native synklepton of Pelophylax bergeri (the parental taxon) and P. kl. (klepton) hispanicus (the hybridogenetic hybrid, which clonally transmits the genome of an extinct ridibundus-like taxon) is present. Until recently, data regarding the presence of alien water frogs in central Italy was scarce, and no alien taxa have been reported for Tuscany. In this study, four distinct non-native Pelophylax lineages have been identified via molecular analysis in the Cecina and Arno river basins and ascribed to the Marsh frog group (P. ridibundus sensu lato). Alien Pelophylax ridibundus, P. kurtmuelleri, and P. cf. bedriagae sensu stricto currently appear to be widespread in the Cecina basin. Furthermore, evidence of hybridisation with autochthonous taxa has been suggested by genetic analyses in four out of eight sampling localities. With a view to evaluate urgent conservation strategies, a greater sampling effort is required to assess the actual distribution and ecology of the alien lineages, and further research is necessary to measure their impact on the native hybridogenetic system of the central-southern Italian pool frogs.

Keywords: European water frogs, conservation, Pelophylax ridibundus, Pelophylax cf. bedriagae, Pelophylax kurtmuelleri, hybridisation

Ref: https://doi.org/10.33256/hj30.3.147158

Authors: Giacomo Bruni, Ivan Mirabella, Dario Domeneghetti, Mauro Fasola & Adriana Bellati

https://doi.org/10.33256/hj30.3.147158

Authors: Giacomo Bruni, Ivan Mirabella, Dario Domeneghetti, Mauro Fasola & Adriana Bellati

https://doi.org/10.33256/hj30.3.159167

pp. 159-167

Authors: Susanna Phillips, Matthew Geary, Matthew Allmark, Sarah Bennett, Kim Norman, Rachel J. Ball, Catherine M. Peters & Anna P. Muir

Abstract: Genetic monitoring is an important, but frequently lacking, component of management actions to support long-term persistence in reintroduced populations. Populations that remain small, due to demographic processes and genetic diversity, are more likely to experience a second extinction event. The natterjack toad (Epidelea calamita) is legally protected in Britain and was the subject of a reintroduction programme in the 1990s. However, subsequent genetic assessment has been mostly lacking. The aim of this study was to assess the genetic diversity of two reintroduced populations of natterjack toads in order to inform conservation management. Adults were sampled and nine microsatellites amplified to assess neutral genetic variation within each site and for comparison with the source population. Inbreeding was observed at the reintroduction sites, as evidenced by high FIS values (0.43 and 0.72), low observed compared to expected heterozygosities, and significant deviation from Hardy-Weinberg equilibrium. Observed heterozygosity is currently lower in the reintroduction sites than it was in the source population at the time of the reintroductions (Red Rocks: 0.15±0.20; Talacre: 0.12±0.20; Ainsdale (source): 0.29). Evidence for a bottleneck was not found, although this is likely a result of sampling overlapping generations. No withinsite population structuring was observed. Such low genetic diversity has not previously been recorded in any natterjack population. Genetic rescue, combined with pool creation, is the most viable option for safeguarding the species at these
sites into the future. Our work highlights the importance of ongoing genetic monitoring, in collaboration with conservation organisations, to support conservation management.

Keywords: Reintroduction, amphibian, inbreeding, conservation, natterjack, genetics

Ref: https://doi.org/10.33256/hj30.3.159167

Authors: Susanna Phillips, Matthew Geary, Matthew Allmark, Sarah Bennett, Kim Norman, Rachel J. Ball, Catherine M. Peters & Anna P. Muir

https://doi.org/10.33256/hj30.3.168172

pp. 168-172

Authors: Gabriela M. Jofré & Christopher J. Reading

Abstract: Cannibalism is a widespread behavioural trait in nature and snakes are no exception. In smooth snakes (Coronella austriaca) it has only been visibly observed in captive individuals or known from faecal/stomach content analyses. Between 2009 and 2018 one incidence of cannibalism, determined from a faecal sample, and one sighting, were recorded in wild smooth snakes in Wareham Forest plantations, UK. Analysis of faecal samples and visual encounter surveys were used to estimate its frequency. Both records occurred in early autumn and our results suggest that its incidence in wild smooth snakes in southern England is low (0.1-0.3 %) and may be the result of low body condition. The circumstances resulting in cannibalism in the smooth snake may also be relevant to other animal species where cannibalism has been reported.

Keywords: body condition, carrion cannibalism, intraspecific predation, maternal predation, ophiophagy, predatory cannibalism

https://doi.org/10.33256/hj30.3.173176

pp.173-176

Authors: Tom Major, Devlan R. Alkins, Lauren Jeffrey & Wolfgang Wüster

Abstract: Marking individuals is a key component of many ecological studies, but with some animals, such as juvenile snakes, it has proven problematic because of size constraints. This impedes our understanding of their habits in the wild. We marked juvenile Aesculapian snakes (Zamenis longissimus) in North Wales with visible implant elastomer (VIE), and recaptured them the following season. Our results demonstrate that the use of VIE is an effective marking method for small snakes, negating the need for tissue removal when marking. We suggest it represents a promising development in the ecological study of snakes, and is especially useful in species that undergo ontogenetic pattern changes.

Keywords: Capture-mark-recapture, ecology, tagging, fluorescent, ontogenetic change