The Herpetological Journal

pp. 239-244

Authors: Zaida Ortega, Abraham Mencía & Valentín Pérez-Mellado

Abstract: We studied the thermal ecology of the montane Iberian rock lizard, Iberolacerta monticola, in the western area of its distribution at the Serra da Estrela (Portugal). We calculated the precision of thermoregulation and the indices of thermal quality of the habitat, and accuracy and effectiveness of thermoregulation. To complete the study of the thermal ecology, we assessed the
relationships between body and environmental temperatures, and we described the thermal and spatial heterogeneity of the habitat. Our results indicate that the Iberian rock lizard is a cold-specialist, with a preferred temperature range between 29.80 and 31.60 °C. Thus, precision of thermoregulation is 1.8 °C, which is a normal range in thermal specialists, like other species of the genus Iberolacerta. This result is important because being thermal specialists and living in mountaintops make Iberian mountain lizards particularly vulnerable to global warming. The habitat of I. monticola at the Serra da Estrela is formed of microhabitats offering different operative temperatures, which allows lizards to select the most suitable for thermoregulation at any time of the day. Iberian rock lizards achieve an effectiveness of thermoregulation of 0.86, thanks to careful thermoregulatory behaviour. Rocky microhabitats occupy more than 50% of its habitat, so is probable that lizards are selecting rocks to warm themselves faster, minimising the costs of thermoregulation. A possible thigmothermic component of this kind would be unique among the species of Iberolacerta.

Keywords: thermoregulation, cold-specialist, global warming, lizard, mountains, Iberolacerta monticola, Lacertidae, thigmothermy

pp. 245-251

Authors: Luca Luiselli

Abstract: Emys orbicularis persica is one of the ecologically least known subspecies of the widespread European pond turtle. Populations of this subspecies were studied in springtime at two extended wetlands of Azerbaijan, and data on density, habitat use, and food habits were collected. These turtles exhibited a mono-peaked diel activity pattern, with peaks during midday hours.
Highest mean estimated densities were found in reed-bed habitat (9.51 individuals × ha-1) and in the open water habitat (lake)
(9.12 individuals × ha-1), with much lower values in seasonally inundated grasslands (6.0 individuals × ha-1) and no turtles
being found in temporary ponds. Density of reeds did not influence the selection of micro-habitat by turtles. Sex-ratio was
even, and females attained larger size than males. Diet was carnivorous and relatively specialised, with large larvae of aquatic
beetles (Hydrophilus piceus) accounting for by far the main prey item. In this regard, the food habits of the Azerbaijan turtles
appeared more specialised than those of other E. orbicularis populations from elsewhere.

Keywords: Azerbaijan, diet, habitat use, natural history, population density, turtle

pp. 252-257

Authors: Raciel Cruz-Elizalde, Aurelio Ramírez-Bautista & Abraham Lozano

Abstract: It is well known that geographic variation in morphological traits occurs among populations of lizard species. In this study, we analysed body size and sexual size dimorphism among four populations of the lizard Sceloporus variabilis from contrasting elevations. Males from all populations were larger than females in snout-vent length, head length, head width, tibia length, and forearm length. These findings are consistent with the hypothesis that sexual selection acts more strongly on males than on females. Females from higher elevations were larger in size than those found at lower elevations, which could be explained
by an increased investment in body size to maximise reproductive success. We suggest that environmental (precipitation,
temperature) and ecological (food, competition, predation) factors influence the expression of sexual dimorphism and
morphological variation in S. variabilis.

Keywords: Sexual dimorphism, body size, populations, lizard, morphological characteristics

pp. 258-265

Authors: Paolo Casula, Leonardo Vignoli, Luca Luiselli & Roberta Lecis

Abstract: Visual counts gathered within citizen science programs are increasingly used to determine distribution and abundance of
species of conservation concern. However, to obtain reliable patterns from counts, imperfect detection should always be
considered, with particular reference to rare and elusive species. By analysing data from a citizen science monitoring program
based on multiple simultaneous observers, we studied detection probability of the Sardinian mountain newt, Euproctus
platycephalus. Detectability of individual newts widely varied among observers, and was positively affected by the number of
newts exposed to during sampling. Training, although appearing to improve detectability, did not accommodate for differences
among trained observers. No effect of sampling hour, tree shade, cloud cover, water flow, turbidity, and temperature was
found, possibly due to standardisation of sampling conditions. Depending on observer’s skills and the population exposed
to during sampling, detection probability of newt populations can widely vary. Most of the sampling units (pools) had few
newts exposed to during sampling, with a high probability of recording false absences. Herpetological surveys could be more
extensively based on multiple simultaneous observers to reduce observer heterogeneity bias in the detection process, and
obtain more reliable patterns of species abundance and distribution for conservation purposes.

Keywords: detection probability; Euproctus platycephalus, multiple observers, observer heterogeneity; visual counts, citizen science

pp. 266-275

Authors: Claudia Olivera-Tlahuel, Hibraim A. Pérez-Mendoza, J. Jaime Zúñiga-Vega, Laura C. Rubio-
Rocha, Brian C. Bock, R. Isaac Rojas-González, J. Gastón Zamora-Abrego, Esteban Alzate,
Angela M. Ortega-León, R. Jonathan Maceda-Cruz, Fausto R. Méndez-de la Cruz, Héctor H.
Siliceo-Cantero & Ricardo Serna-Lagunes

Abstract: Toe-clipping is an extensively used technique for individual identification of amphibians and reptiles. However, this method might result in negative effects including reduced survival. In this study, we used capture-mark-recapture data obtained from ten different lizard species, including more than one population for two species, to examine whether survival rates varied as
a function of the number of toes that were clipped. We used likelihood methods and multi-state models to estimate survival
probabilities. Specifically, we tested if the number of clipped toes had an effect on annual survival, comparing survival among
groups of individuals that shared the same number of toes that were clipped. We found clear reductions in survival associated
with the removal of several toes in seven study sites that correspond to five different species. These represent 37% of all
the species and populations that we examined. Therefore, we conclude that this marking method potentially causes severe
damage and may lead to biased parameter estimates in ecological studies of lizard species. Whenever possible, toe-clipping
should be avoided and replaced by less invasive methods for individual identification.

Keywords: Dactyloidae, marking methods, Phrynosomatidae, survival, toe-clipping, Xenosauridae.

pp.276-286

Authors: Don Moll & Lauren E. Brown

Abstract: Over a half-century ago, C. W. Hibbard proposed a climate theory based on imported living giant tortoises (“Geochelone”) as proxies that suggested the climate adaptations of giant fossil tortoises of the Cenozoic Era (65.5 million years ago to present) were subtropical or tropical across much of North America. This has been a prominent and enduring paleoclimate theory. We show that incorrect assumptions and other problems invalidate this theory. Seven alternative concepts are presented that suggest North American fossil giant tortoises could have evolved necessary adaptations including cold-adaptive morphology,
behavioural thermoregulation, burrowing, use of caves as shelters, tolerance of prolonged cessation of food consumption,
cryoprotection and supercooling (protection from freezing), and gigantothermy (metabolic and structural thermoregulation)
to survive northern winters and in montane areas. This study illustrates the potential danger of using an inappropriate proxy
to predict past climates.

Keywords: Testudinidae; Geochelone; Hesperotestudo; giant tortoises; fossils; climate; morphology; behavioural
thermoregulation; burrowing; caves; feeding cessation; cryoprotection; supercooling; gigantothermy; proxies

pp.287-298

Authors: S. Edwards, K.A. Tolley & G. J. Measey

Abstract: Direct anthropogenic factors (e.g., habitat loss, fragmentation, and degradation) threaten many amphibian populations,
however some declines have occurred in supposedly pristine environments with no obvious causes. These enigmatic declines
may be due to shifts in environmental factors influencing development and ultimately adult survival. Rose’s mountain toadlet
Capensibufo rosei has undergone such an enigmatic decline, with several populations presumed to be locally extinct at historic
breeding sites. The two remaining breeding sites (Silvermine (SILV) and Cape of Good Hope (CGH)) on the Cape Peninsula of
South Africa were monitored for three years (2012-2014) for life history traits and ecological requirements. Males congregate
at ephemeral pools during the middle of the austral winter, with females arriving to lay eggs and then immediately leaving.
Breeding only occurs in a few of the available pools. We hypothesised that larval development in colder, deeper pools would
result in smaller-bodied tadpoles, and ultimately in relatively smaller adults. Pools at SILV were significantly deeper and colder
compared to CGH, with breeding occurring in pools that were 27.05±10.21 mm and 21.55±6.95 mm deep at SILV and CGH,
respectively. Contrary to expectations, breeding adults and developing tadpoles at SILV were larger than CGH individuals. The
percentage of non-developing eggs at CGH was high compared to SILV and other anuran species. Development within this
threatened species may be influenced by pool characteristics, which could provide clues as to the factors that influenced local
extinctions in historical populations.

Keywords: amphibian; aquatic habitat; bufonid; development; montane; tadpole

pp.299-306

Authors: Mainara Xavier Jordani, Lilian Sayuri Ouchi de Melo, Cassia de Souza Queiroz, Denise de
Cerqueira Rossa-Feres & Michel Varajão Garey

Abstract: The analysis of species richness and community composition provides basic information to understand the structure of species assemblages. Here, we compared species richness and composition, compositional similarity and species turnover of tadpole communities in 14 lentic and eight lotic habitats in the Atlantic Rainforest of southeastern Brazil. Because the occurrence
in lotic habitats requires some degree of morphological or behavioural specialisations of tadpoles to fast flowing water, we
expected to find low species richness and species turnover in lotic than in lentic habitats. We compared species richness using
abundance and sample-based rarefaction and species composition by PERMANOVA. We analyzed the Species Abundance
Distribution (SAD) in each habitat type using a Whittaker diagram. To assess the similarity in species composition, we used
a hierarchical cluster analysis. We compared the beta diversity between lentic and lotic habitats using Whittaker index and
the species turnover using Jaccard index. We recorded 26 anuran species in the larval stage belonging to seven families. The
highest species richness was recorded in lentic habitats (20 species), whereas only seven species occurred in lotic habitats.
The species composition also differed markedly between lotic and lentic habitats, with only one shared species (Aplastodiscus
eugenioi). Both habitats had few dominant and rare species and a greater proportion of species with intermediate abundance,
but different processes are underlying this distribution abundance pattern in each type of habitat. Our results indicate that
species richness, abundance, and occurrence are associated to habitat type (lentic and lotic), indicating a possible effect of the
environmental filtering process associated to different life history strategies.

Keywords: Amphibians; Community ecology; Species composition; Species diversity; Species turnover.