AUTHOR: STEVEN J.R. ALLAIN

AUTHORS: ELIAS TZORAS, BOYAN ZLATKOV, SYLVIA GEORGIEVA & VLADISLAV VERGILOV

AUTHORS: PAUL WHITEMAN & STEVEN J.R. ALLAIN

AUTHORS: KRISTÓF MÁTÉ KOVÁCS & GERGELY HORVÁTH

AUTHORS: VICTOR CADET & RAPHAËLLE PASCO

AUTHORS: JOSÉ CÂMARA, LUENA SORAYA, VICENTE L. MIGUEL & JOSÉ JESUS

AUTHORS: ALESSANDRO PATERNA & MARIO MARCONI

AUTHORS: MASSIMO CAPULA, GIAMPIERO CAMMERINI & STEFANO SARROCCO

AUTHOR: JUAN PABLO DURANGO

AUTHOR: IVAN SAZIMA

AUTHORS: PRASUN MANDAL & PRIYANKA HALDER MALLICK

AUTHORS: BRISTOL RIGBY, RICHARD A. GRIFFITHS & NICK DOBBS

ABSTRACT: Northern vipers Vipera berus are declining and increasingly confined to fragmented and isolated populations in England. Scale anomalies that occur during development can potentially be related to environmental stressors. Using photographs of the dorsal view of viper heads, we compared levels of head scale fragmentation and asymmetry between four populations to identify the extent of anomalies. Although all populations had vipers that displayed scale fragmentation and asymmetry, the incidence of such anomalies was lowest at Fackenden Down which supports the largest population and is probably the least isolated. Two populations that displayed particularly high levels of scale anomalies – Talbot Heath and Turbary Common – are isolated and surrounded by urban and suburban development. Supraocular and intercanthal scales showed a higher incidence of fragmentation and asymmetry than did apical scales, and there was a general tendency for the vipers with scale fragmentation to also display asymmetry. We speculate that the relatively high incidence of scale anomalies in small, isolated populations may be a result of environmental or genetic pressures and that head scale fragmentation and asymmetry may provide an early indication of such stressors.

AUTHORS: CHRISTOPHER J. MICHAELS & JOSÉ ALFREDO HERNÁNDEZ DÍAZ

ABSTRACT: The Lake Alchichica salamander Ambystoma taylori is a Critically Endangered, neotenic inhabitant of a single, hyposaline lake in Puebla, Mexico. Between 2015 and 2018, initial field data were collected for this understudied species, to inform future conservation action. Using unbaited submerged passive traps at depths of 0–<10, 10–<20 and 20–30 m, we captured 240 salamanders (137 males, 82 females, 18 juveniles) over 32 visits, for which length and mass were collected, and which were individually identified. Generalised linear models showed that males were captured at greater rates than females, and capture rates were lower in the dry-warm and wet-cold seasons than the wet-warm and dry-cold seasons. Salamanders were more likely to be captured at depths of 20 and 30 m than 10 m, but this effect was not detected when using only presence/absence data, suggesting clustering of animals in the lake. No evidence was found that depth of capture was predicted by size, sex or season. No eggs and only a small number of juveniles were detected, which were found in all seasons and without a clear trend in size across the year, meaning that a clear breeding season could not be identified. It is noteworthy that hatchling larvae would be able to escape the traps due to mesh size. Adult mass had a significant, positive cubic relationship with SVL, but females were heavier for their lengths, especially at larger sizes. Conversely, males were slightly but significantly longer than females for their weight (despite shorter absolute SVLs than females). These trends are typical in salamanders and likely associated with investment in eggs. Approximately 12% of animals carried an unidentified ectoparasitic burden and endoparasites Hedruris siredonis were detected in opportunistically encountered dead animals that were necropsied. Data reported here provide an initial insight into the biology and phenology of this species, as well as offering viable survey methods in a challenging environment.

AUTHORS: JOY ARPITHA & SHAMA GANESH

ABSTRACT: The Dattatreya night frog Nyctibatrachus dattatreyaensis, found in the Chandra Drona Parvatha massif, is a stream-dwelling, evolutionarily distinct and globally Endangered species threatened by increasing habitat loss and alteration. We examined the stomach contents of 104 individuals, from ten different streams, of which 42 had prey in their stomachs. The prey items were in 12 orders across 4 classes, mainly dipterans, hymenopterans and lepidopterans. The frog exhibits a passive foraging mode, has a moderate trophic niche breadth (Bst = 0.43), and may have a preference for agile prey. Apart from this, there were plant materials, sand grains and plastic debris found in the stomach contents, with 0.82 mm³ of plastic debris found in eight individuals across three streams. The presence of plastic debris indicates the impact of anthropogenic activities leading to a form of habitat degradation. The data presented indicates the need for immediate and efficient conservation strategies to be put in place for this understudied species.

AUTHORS: NIKITA POKHILYUK & IRINA MASLOVA

ABSTRACT: Body-bending behaviour or kinking is a cryptic form of immobility, believed to be used by snakes to avoid predation. Originally, this defensive strategy was thought to be used only by arboreal species in the Neotropics but recent reports suggest that it may be more widespread than previously thought. For the first time, data is presented on this type of behaviour for three snake species of east Asia - Elaphe dione, Elaphe schrenckii and Gloydius ussuriensis.