To understand habitat use of juvenile Florida box turtles, Terrapene carolina bauri, I combined data gathered from periodic direct observation as well as from continually monitored individuals on Egmont Key, Florida. Habitat use of juveniles differed from that of adults, but this population did not demonstrate total habitat partitioning among size classes. Juveniles were found most commonly within a single habitat type, Palm Pepper Forest, and did not display the flexibility in habitat use seen in conspecific adults. Microhabitats with dense cover, particularly Brazilian pepper (Schinus terebinthifolius), were used preferentially by juveniles in this population. Juvenile turtles were found most frequently in areas with leaf litter and moist soil substrates. Florida box turtles are of conservation concern, and habitat requirements of juveniles should be considered in management decisions.

Males from different iguanian lizard species engage in frequent visual signaling during agonistic interactions, mainly by displaying head bobs. We conducted a detailed study of the structure of head bob displays mediating male agonistic interactions in Liolaemus lemniscatus lizards. We staged pair-wise encounters where one male, the intruder, was placed in the terrarium of a conspecific male, the resident. During these interactions, males exhibited only one type of head bob display made up of three distinct units: a low amplitude bob (unit 1), a brief pause (unit 2), and two consecutive high-amplitude bobs (unit 3). Head bob displays occurred singly or as a part of a bout, with a mean number of head bob displays per bout of two. Total head bob display duration was stereotyped. The highest inter-individual variation (duration and amplitude) was recorded for unit 3, suggesting that this unit may provide information about the individual identity of the sender. Winners of interactions performed more head bob displays than losers, and these were composed of units of longer duration and higher amplitude than head bob displays exhibited by losers. Although preliminary, our results suggest that, in L. lemniscatus, head bob displays may facilitate opponent assessment by conveying information about individual fighting ability, motivation, or dominance status.

The sex of young sea turtles is difficult to determine because they lack externally dimorphic characteristics and heteromorphic sex chromosomes, yet internal dimorphic morphology is defined at hatching. We tested the reliability of nine internal gonad and accessory duct characteristics to identify the sex of 558 posthatchling loggerhead sea turtles accurately. We modified existing laparoscopic procedures, previously used to classify the sex of larger sea turtles and other turtle species, for use in posthatchlings. Here we describe our approach and quantify the reliability of our morphological criteria. Sex was verified by histological examination of gonadal biopsies from a subset of the turtles. We noted seasonal shifts in early gonadal structure so that some characters which were reliable in the summer and fall were not reliable other times of the year. Thus, we confined the analysis to the six characters that were reliable year round: gonad shape, paramesonephric duct size, gonad size, paramesonephric duct lumen presence, paramesonephric duct mobility, and gonad attachment. Using discriminant analyses of the biopsy and morphological data, we found high correlations between sex from tissue biopsies and these six morphological characters; this analysis misclassified just 2% of the animals with histological verification. Applying the classification functions to animals without histology and comparing those results to our visual classification resulted in 2% reclassification. The analysis reclassified animals that we or the histology correctly identified that had both female-like and male-like characters. Our method provided accurate identification of sex in very young sea turtles. This methodology enables sex ratio assessments in early life stages, which are critical to species recovery efforts. Additionally, sex assignment data are basic to our understanding of patterns and processes directing dimorphic changes of the gonads and their ducts.

We examined whether the presence and developmental stage of conspecific egg masses affected the choice of oviposition site by the Japanese brown frog, Rana japonica. A paired choice experiment was conducted in nine field enclosures, each containing one empty artificial pool and one containing conspecific egg masses at different developmental stages. Adult R. japonica almost always selected the tub with the resident egg mass for their oviposition site if the resident egg mass was younger than Gosner's stage 16, but avoided tubs that contained older egg masses. We hypothesized that the potential of cannibalism from conspecific residents increases as the resident eggs develop, which affects the choice of oviposition site by adult R. japonica.

Concepts of vertebrate succession in terrestrial habitats are based mainly on studies of birds and mammals. To provide a broader understanding of vertebrate succession and the organization of species assemblage, we studied the development of a herpetofaunal assemblage in a reforestation project. We sampled herpetofauna monthly between February 2001 and March 2002 and between June and September 2003 in a reforested limestone valley, and compared the composition and structure of the species assemblage in this valley with three reference sites and a deforested valley in a limestone region of Puerto Rico. In the reforested valley, the increase in vegetation heterogeneity and the decrease in microclimate variability facilitated herpetofaunal succession. Species richness increased rapidly from three to eleven species in 13 mo, with predatory species colonizing the reforested valley by the end of the study. The trophic structure changed more slowly with the density of individuals of (1) arboreal species increasing with increased woody vegetation cover, and (2) predatory species increasing with increased prey density. The pattern of herpetofaunal succession can be described by an assembly rule that considers microclimate as an important controller for the development of the species assembly. We suggest that including microclimate in assembly rules can help us broaden our understanding of factors that determine vertebrate succession in terrestrial habitats.

For many taxa, little is known about whether territoriality of adults affects the behavior of juveniles. Laboratory research has shown that aggression of adult territorial red-backed salamanders (Plethodon cinereus) decreases with familiarity, but it is not clear whether juveniles are randomly or nonrandomly associated with adult or parental territories. Using data from mark-recapture surveys, we compared the number of captures of first-year juveniles and adults of P. cinereus to ambient meteorological data. We found no evidence for temporal separation of foraging; weather conditions did not affect the proportion of first-year juveniles captured. We then conducted nearest-neighbor analyses to evaluate whether first-year juveniles were spatially associated with or disassociated from adult home ranges. Juveniles were neither closer to nor further away from adults than would be expected by random chance. Nearest-neighbor distances also were not significantly different from the mean radius of adult home ranges. There was no evidence that the distribution of adult home ranges affected the distribution of juveniles, at least after recent rainfall events; there is a possibility that interactions between age classes may occur under drier conditions.

Transformation of habitats for agriculture is one of the main causes of reduction in diversity worldwide. We observed reproductively-active female turtles of Trachemys dorbignyi and their nests from 1995 to 2001 in an intensively farmed area in southern Brazil. The area was selected because of the existence of a previous study done 20 yr earlier in the same locality, which allowed us to evaluate the possible effects of human activities on the reproductive ecology of T. dorbignyi. Nesting occurred between October and January, with most activity in November and December (the warmest months). An average of 31% of the females nested in each year, laying up to three clutches at intervals of about 15 days. The females usually constructed nests between 0,700 and 1100 h and deposited 6 to 19 eggs (mean = 12.1) per nest. Clutch size was strongly correlated with carapace length. The eggs were, on average, 39.3 ± 1.73 mm long and 25.8 ± 0.91 mm wide, with a mean mass of 14.9 ± 1.29 g. Multivariate Analysis of Variance showed that egg size differed from year to year. In spite of the intense human activity, the parameters analyzed were nearly unchanged after two decades. However, aspects such as reproductive success, reduction of nesting sites, and the effects of agrotoxins, which could affect the long-term conservation of the species, were not assessed.

Amphibian populations in several regions of the world appear to be declining due to infectious diseases. While many studies have attempted to identify the pathogens associated with specific declines, very few studies have attempted to identify the natural microflora that is present on amphibian skin. Knowledge of the natural flora that healthy individuals carry may, in some cases, provide valuable information for understanding disease outcomes. In this study, we isolated the natural bacterial flora found on the skin of apparently healthy adult eastern newts (Notophthalamus viridescens), larval bullfrogs (Rana catesbieana) and redback salamanders (Plethodon cinereus) living in natural field sites in Virginia. We positively identified five bacterial species from newts, three bacterial species from bullfrogs and four bacterial species and one yeast from redback salamanders. In a parallel study, we examined the physiological profiles of bacterial communities at six sites with newt and bullfrog tadpole populations. A cluster analysis resulted in two main groupings: one for all the water samples and one for all the skin swab samples from the amphibians. This result suggests that only a sub-set of bacteria in the environment are able to successfully colonize amphibian skin.

Ctenophorus is the largest genus of Australian agamid lizards, with an extensive radiation in the arid zone. Here we describe a distinctive new dragon species—Ctenophorus nguyarna—from the isolated Lake Disappointment in Western Australia. The new species is characterised by heterogeneous dorsal scales tending to form vertical rows on the flanks, a reticulated orange and black background color, and black bars on the dorsum and black vertical bars on the tail. To provide a molecular context as to the distinctiveness and placement of the new species we analysed five sequences of Ctenophorus sp. nov., two new sequences of C. salinarum and 11 previously published sequences of Ctenophorus species, representing ~1573 bases of the mitochondrial genome. Our phylogeny strongly supports at least two independent origins of salt lake specialization in both the western and eastern arid zone. Based on molecular data the sister taxon is C. salinarum, which is also associated with salt lakes in Western Australia. The other specialist is the Lake Eyre Dragon (C. maculosus) from South Australia that lives on and under the salt crust itself, and has a number of unique derived characters for Ctenophorus. There are likely to be other new species of agamid lizards in Australia's vast and little-explored arid zone.

A new species of Oreophrynella is described from Mount Ayanganna, a 2000 m plateau in the Pakaraima Mountains in west-central Guyana. The new species can be distinguished from other species of Oreophrynella by large size (snout–vent length up to 37.3 mm in females; 26.7 mm in males) absence of frontoparietal crests, orange-colored dorsum, and creamy yellow venter.

A new species of arboreal Eleutherodactylus is described and assigned to the Eleutherodactylus unistrigatus Group from the Amazonian lowlands of northern Departamento de Cusco, Peru. The new species was found on vegetation 150–800 cm above ground, has a SVL up to 21.9 mm, and is distinguished from other species of the genus by having a green dorsum with white spots; a pointed, brown snout; and by lacking a tympanic membrane and annulus. Males lack vocal slits and nuptial pads; females are unknown.

A new species of bent-toed gecko, Cyrtopodion brachykolon is described from a series of specimens collected in 1991 from Manshera and lower Swat districts, Northwest Frontier Province, Pakistan. Specimens were examined for 45 morphological characters and measurements. Cyrtopodion brachykolon is distinguished from the morphologically similar species, Cyrtopodion walli (Ingoldby 1922), by the former's relatively shorter limbs, smaller dorsal tubercles relative to the surrounding granular scales, indistinct longitudinal rows of enlarged dorsal tubercles, and fewer number of transverse color bands. Another morphologically similar species, Alsophylax (Altiphylax) tokobajvi Eremschenko and Szczerbak 1984, can be separated from this new species by its larger supranasal scales and less angularly bent or straight digits. We also provide a brief review of the taxonomic history of the bent-toed geckos of Pakistan, herein assigned to Cyrtopodion (s. l.).

We describe a new species of the Eleutherodactylus discoidalis group from cloud forests of the Apurimac and Kosñipata valleys, southern Peru. The new species differs from other species of the group mainly by having a coarsely shagreen dorsum, long and slender hind legs, very long feet, Finger I equal in length to Finger II and fingertips not expanded. The species also lacks supernumerary tubercles on the feet.