The Herpetological Journal

pp. 131-132
Authors: Midwinter, Robin; Rose, Trevor & Griffiths, Richard

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pp. 133-140
Authors: Bainbridge, Loren; Stockwell, Michelle; Valdez, Jose; Klop-Toker, Kaya; Clulow, Simon; Clulow, John & Mahony, Michael

Abstract: Population demographics for amphibian larvae are rarely estimated due to marking technique limitations on small body size, morphological change (metamorphosis), and the associated habitat changes (aquatic to terrestrial environments). A technique that may meet some of these limitations is visible implant elastomer (VIE) tagging. In this study, we report on the efficacy of VIE tagging a tree frog (Hylidae) at the tadpole stage for cohort identification across metamorphosis to the adult stage, in a field environment. During our preliminary captive trial, post-metamorphosis tag retention was 100% over three months, with no adverse effects observed on survival, growth or time to metamorphosis. During our field study tag retention in recaptured Litoria aurea was 95% for tadpoles and 88% across metamorphosis. By 200 days post-tagging, retention declined to 75% in the adult stage and stabilised around 50% by 300 days. Post metamorphosis the retention rate was less reliable and dependent upon sex and life-stage. Females showed the highest retention rate (max. 62%, 760 days post tagging), followed by juveniles (max. 45%, 400 days post tagging) and males (max. 20%, 760 days post tagging). We conclude that VIE tagging is a viable method for studying cohort larval movements and population demographics of amphibians up to a 50 day post-metamorphosis stage.

Keywords: LITORIA AUREA, METAMORPHOSIS, TADPOLE, VIE TAGGING, TAG RETENTION

pp. 141-148
Authors: Souza, Adriano M.; Pires, Renan C.; Borges, Vitor S. & Eterovick, Paula C.

Abstract: Roads have many detrimental effects on natural habitats and their fauna, ranging from altered microclimate to road kills. Animals which move slowly or are attracted to the road surface are particularly threatened. We studied herpetofauna road mortality in a Cerrado ecosystem in central Brazil. We sampled 51 km of state roads during 26 days distributed between dry and wet seasons in 2010 and recorded 109 dead individuals of 34 species of amphibians and reptiles. Including animals found alive on the road, we recorded 159 individuals across 39 species (estimated richness: 48). This number represents about 50% of the herpetofauna species richness expected to occur in a Cerrado site in central Brazil based on a concomitant species inventory. Our study indicates that roads can cause high mortality rates for the Cerrado herpetofauna. We consider that this problem requires urgent attention since economic growth is largely based on agriculture in the Cerrado and construction of more roads is planned to improve harvest transport.

Keywords: REPTILES, WILDLIFE ROAD USE, WILDLIFE ROAD MORTALITY, AMPHIBIANS

pp. 149-154
Authors: Lu, Hong-Liang; Jiang, Chuan-Quan & Ji, Xiang

Abstract: Locomotor impairment during pregnancy can be attributed to physical burden or physiological changes associated with pregnancy. However, the degree to which physical and physiological changes affect reproductive costs likely varies between species. Here, we used the Qinghai toad-headed lizard (Phrynocephalus vlangalii) as a model to assess locomotor costs during pregnancy and the relative impact of physical and physiological effects in pregnant viviparous lizards. The locomotor costs of pregnancy were pronounced: sprint speed decreased gradually throughout pregnancy, reached a minimum at parturition and increased slowly thereafter. The reduced speed in pregnant females was not related to relative litter mass. Compared with the locomotion of non-reproductive females or males, pregnant females exhibited lower speeds and shorter stride lengths. These results suggest that, despite having a physical effect on locomotor performance, physiological changes associated with pregnancy likely play a major role in locomotor impairment in pregnant P. vlangalii.

Keywords: PHRYNOCEPHALUS VLANGALII, REPRODUCTIVE COSTS, STRIDE LENGTH, AGAMIDAE, LOCOMOTOR PERFORMANCE, PHYSICAL BURDEN

pp. 155-161
Authors: Sewell, David; Baker, John M.R. & Griffiths, Richard A.

Abstract: Grass snakes (Natrix natrix) were monitored for nine years on a site in eastern England restored for an amphibian reintroduction. Counts of snakes increased between 2004 and 2012 from 1.25 to 3.83 snakes per survey visit. Grass snake counts were positively correlated with the number of common frog spawn clumps each year and peak counts of pool frogs. During surveys and incidental encounters 137 adult males, 161 adult females, 131 juveniles and 44 hatchlings were captured and individually photographically identified. Captures of hatchlings were erratic and recapture rates were low, so they were excluded from the analysis. Annualised capture data were analysed in the capture-recapture programme MARK, using the Cormack-Jolly-Seber model. The top ranked model gave an apparent annual survival rate of 0.66 (95% CI=0.543–0.755) and an individual detection rate of 0.17 (0.118–0.245). Population estimates based on this model ranged from 53 (95% CI=37–76) to 576 (95% CI=400–831) over the nine years of study. Grass snake population estimates were equivalent to densities of 4.8 to 52.4 individuals ha^-1. Nevertheless, it is unlikely that these snakes were permanently resident within the study area, and annual survival may therefore be underestimated. A more plausible explanation for the large population estimates is that the snakes were temporarily resident within a patch of high quality habitat and moved through home ranges that included the study site.

Keywords: MONITORING, CORMACK-JOLLY-SEBER, NATRIX NATRIX, POPULATION ESTIMATE

pp. 163-167
Authors: Biolé, Fernanda G.; Valetti, Julián A.; Grenat, Pablo R.; Salas, Nancy E. & Martino, Adolfo L.

Abstract: Chiggers of the genus Hannemania occur in the Americas and are intradermal parasites of amphibians. In the present study, we examine the infestation of Hannemania achalai on the sister anuran species Pleurodema kriegi and P. cordobae. A total of 248 individuals were examined to quantify prevalence, mean abundance and mean intensity of infestation. Infestation rates in P. kriegi juveniles were lower than in adults. The abundance and intensity of infestation did not differ between host sexes. In adults, chigger prevalence on P. kriegi (92%) was notably higher than on P. cordobae (42%), which is also reflected in mean intensity (40.3 and 14.4 chiggers per infested host, respectively) and abundance (36.9 and 6.0 chiggers per individual, respectively) between species. The vent region and hind limbs had the highest parasite load. This study for the first time reports the presence of this parasite in P. cordobae, and represents the first comparative study of population estimators and Hannemania preference between taxonomically related species of frogs.

Keywords: PLEURODEMA KRIEGI, CHIGGERS, AMPHIBIA, PARASITISM, HANNEMANIA ACHALAI, PLEURODEMA CORDOBAE, PREVALENCE

pp. 169-176
Authors: Matías-Ferrer, Noemí & Escalante, Patricia

Abstract: Habitat disturbance is one of the main factors contributing to population declines. Changes in the amount and quality of available habitat can affect body condition and morphology. In this study we evaluated the effect of habitat disturbance (deforestation, urbanisation and land-use change) on body size, body condition and fluctuating asymmetry in two species of arboreal tropical frogs (Agalychnis callidryas and Dendropsophus ebraccatus) at Los Tuxtlas Biosphere Reserve, Veracruz, México. We did not find significant differences in body condition or body size associated with habitat disturbance in A. callidryas, although the species reduced its local distribution in line with habitat disturbance. In D. ebraccatus, on the other hand, we observed a significant relationship between body condition and size with habitat disturbance. It is unknown whether these changes are adaptive or compromise the permanence of populations. Fluctuating asymmetry indices for both species exhibited no significant differences except for the tibia-fibula length of D. ebraccatus, which was significantly higher in undisturbed habitat.

Keywords: BODY SIZE, FLUCTUATING ASYMMETRY, DENDROPSOPHUS EBRACCATUS, HYLIDAE, AGALYCHNIS CALLIDRYAS, BODY CONDITION, HABITAT DISTURBANCE

pp. 177-186
Authors: Urošević, Aleksandar and Ljubisavljević, Katarina and Ivanović, Ana

Abstract: We explored individual variation and asymmetry in the skull shape of the common wall lizard (Podarcis muralis Laurenti, 1768) across four populations representing different habitats, by employing geometric morphometrics. We found directional and fluctuating asymmetry across the analysed populations, without differences in fluctuating asymmetry among populations. Patterns of individual variation and fluctuating asymmetry were highly correlated within and among populations. Asymmetric skull shape variation was similar in all populations, and was mostly related to the jaw adductor muscle chamber. Our results imply that the uniform pattern of skull fluctuating asymmetry results from a high level of canalisation. Directional asymmetry can be related to anatomical and behavioural lateralisation.

Keywords: PODARCIS MURALIS, FLUCTUATING ASYMMETRY, SKULL, VARIATION, ISLAND

pp. 187-190
Authors: Luiz, Luciana Frazão; Contrera, Felipe Andrés Leon & Neckel-Oliveira, Selvino

Abstract: Diet and transportation of tadpoles by Ameerega trivittata was studied in the eastern Amazon basin. A total of 56 specimens (48 males and 8 females) were sampled, 44 out of which had quantifiable stomach contents. Forty males were recorded to carry between 1 and 18 tadpoles. Forty pools were measured and sampled for tadpoles and odonate naiads, a putative tadpole predator. Myrmicine ants predominated in the diet of males, putatively leading to higher concentrations of alkaloids beneficial during tadpole transport. No relationship was found between male size and the number or size of tadpoles transported, and between pool size and tadpole abundance. The number of tadpoles in the pools was negatively related to the abundance of odonate naiads.

Keywords: PREDATION, FLUSHING, DENDROBATID, POOLS, ODONATA

pp. 191-195
Authors: Beaty, Lynne E.; Nyarko, Kwesi & Bernal, Ximena E.

Abstract: Light-induced pigmentation changes are widespread among tadpole species. In this study we characterised light-induced changes in melanin dispersion through development in cane toad tadpoles (Rhinella marina). We describe a pattern of light-induced pigmentation change in which tadpoles are darker in the presence of light and lighter in darkness until the onset of metamorphosis. This pattern contrasts with that of other non-bufonid tadpole species, but mimics the pattern of pigment change exhibited by embryonic anurans. We discuss our results in light of the ontogenetic changes in toxicity to evaluate the photoresponse of cane toad tadpole pigments as a potential aposematic signal, neotenic trait, and thermal adaptation.

Keywords: CAMOUFLAGE, ONTOGENY, BUFO MARINUS, APOSEMATIC, TOXICITY, MELANOPHORE, PIGMENT CHANGES