The common lizard (Lacerta vivipara) is a small, nonterritorial, live-bearing lacertid that is sexually dimorphic in several morphological traits (e.g., tail length, snout–vent length, head size). Using microsatellites, we examined paternity in a wild population and investigated whether sexual dimorphism could be the result of intra- or intersexual selection. We found multiple paternity in 65.4% of 26 clutches. There was no evidence of assortative mating. Successfully reproducing males were larger and heavier and had longer tail regenerates or intact tails compared to those that did not reproduce. Tail length and body condition of males were related to the number of offspring sired. However, we found no evidence that head width was related to male reproductive success. We conclude that (1) males with higher body condition index might be more successful in male-male interactions or might be able to search more effectively for females, (2) sex divergence in relative tail length in common lizards reflects the action of sexual selection for male reproductive success, and (3) intersexual dietary divergence could be an alternative hypothesis for head size difference between sexes rather than intrasexual selection.

A new species of treefrog closely related to Bokermannohyla alvarengai is described from Chapada Diamantina centrally located in the State of Bahia, Brazil. In comparison to B. alvarengai, the new species is smaller in size, with less developed forearm and prepollexes, and smaller tympani. We describe the tadpole, advertisement call and provide information on its natural history. We propose the B. alvarengai group to accommodate this species and the new species described here.

A new species of Sibon, placed in the Sibon annulatus species group, is described from the Mosquitia region of northeastern Honduras. Within this group, the new species appears most closely related to Sibon dimidiatus. By comparison to S. dimidiatus, the new species can be distinguished by its fewer ventrals, subcaudals, total number of ventrals plus subcaudals, and smaller adult size.

To study the movement patterns of Green Seaturtle (Chelonia mydas) populations in the Caribbean region using Cuban habitats, tag-recapture data from local (Cuban National Tagging Program 1989–2002) and international programs (1959–2002) were compiled and compared. Of the 742 turtles tagged in Cuba at fishing areas, nesting beaches and head-start facilities, 5.5% were recaptured, mostly outside of Cuban waters and with a majority of these (76.9%) off the coast of Nicaragua. Green Seaturtles tagged elsewhere and recaptured in Cuba included head-started juveniles from Grand Cayman (45% of the total), Mexico (2.3%), and Florida (1.8%); wild juveniles from the Bahamas (14.1%), Bermuda (5.4%), and Florida (1.5%); and adults from Tortuguero (26%), Florida, USA (1.3%), Mexico (1%), Venezuela (1.3%), and U.S. Virgin Islands (0.3%). Recaptures of tags placed at sites north of Cuba (Bermuda and the Bahamas) clustered in the northeast region of Cuba, whereas those from the south (Grand Cayman) were recaptured in southern areas. Recaptures from Tortuguero tags were concentrated in the southeast and westward regions of Cuba. Turtles from the Bahamas, Grand Cayman, and Bermuda showed the highest recapture rates in Cuban habitats, with 3.2, 1.9, and 1.0% of the total number of tags applied, respectively. These results for a broad range of populations and across life stages underscore the regionwide significance of Cuban sites as critical habitats or migratory corridors.

Increased ultraviolet-B (UV-B) radiation reaching the Earth's surface has been implicated in amphibian declines. Recent studies have shown that many amphibian species have differences in sensitivity depending on developmental stage. Embryos and larvae of Ambystoma maculatum (Spotted Salamander) and larvae of Ambystoma talpoideum (Mole Salamander) were exposed to five simulated UV-B treatments in controlled laboratory experiments to determine the relative sensitivity of different lifestages. Hatching success of the embryos exceeded 95% in all treatments; however, the larvae of both species exhibited greater sensitivity to UV-B exposure. Older larvae of A. maculatum that were not exposed to UV-B as embryos were more sensitive than larvae that had hatched during exposure to UV-B. Growth of surviving larvae of A. maculatum was significantly reduced as UV-B intensity increased, whereas growth of A. talpoideum was unaffected. These results were compared to ambient UV-B conditions in natural environments. It appears that the embryo stage is relatively unaffected by UV-B levels observed in natural habitats, probably because of protection from vegetation, organic matter in the water column, oviposition depth, and egg jelly. The larval stage of these species may be at greater risk, particularly if there is an increase in UV-B radiation exposure caused by increases in water clarity and/or decreases in dissolved organic carbon.

Southern Torrent Salamanders (Rhyacotriton variegatus) range widely from north coastal Oregon to northern California but are a patchily distributed inhabitant of forested seeps and headwater springs. We collected bimonthly samples of this species from managed forest sites in the Mad River watershed, Humboldt County. Larvae were measured, marked, and released, but a limited number of transformed individuals were preserved for laboratory analyses. North coastal R. variegatus breeds annually and has an extended courtship and egg-laying period. Cloacal spermatophores were present in gravid females from February through June, and oviposition likely occurs spring through fall. A prolonged larval period (hatching to metamorphosis) lasts 2–2.5 yr; transformed females require another 1.5–2 yr until first breeding, and clutch size averages 7.5 eggs. Adult sizes, size at metamorphosis, and developmental times were comparable to north coastal Oregon R. variegatus, suggesting that a simple north-south, harsh-mild environmental cline does not influence developmental time for coastal populations. Unexpectedly, clutch size and size-fecundity relationships for the California population of R. variegatus were more similar to Rhyacotriton cascadae, an inland, northern species with longer larval periods and larger sizes at metamorphosis, than to R. variegatus in north coastal Oregon. Rhyacotriton variegatus has limited rates of population increase because of long generation times and low fecundities and could be highly sensitive to frequent disturbances that impact numbers.

Plethodontid salamanders provide an opportunity to investigate mating behaviors and pheromonal communication within the context of well-established phylogenetic relationships. Courtship in many members of the genus Plethodon has been well studied, but critical gaps exist in observations of pheromone delivery methods (vaccination or olfactory) in species phylogenetically intermediate between those having the two pheromone delivery methods. I observed courtship interactions in three small eastern plethodontids, Plethodon cinereus, Plethodon angusticlavius, and Plethodon richmondi. I documented several novel female behaviors, as well as interspecific variation in courtship patterns that otherwise have been highly conserved for over 70 million years. I confirmed that olfactory pheromone delivery occurs in P. angusticlavius, a species that is phylogenetically in the transition from vaccination to olfactory pheromone delivery within the genus Plethodon. The deviation from typical courtship patterns observed for the three study species revealed that females play a more active role in courtship than has previously been documented for Plethodon species.

Hibernation sites at higher latitudes must protect snakes from colder conditions for longer periods of time. Because fewer locations are likely to be suitable, hibernation site availability may restrict the northern distribution of snakes. We considered overwinter mortality, hibernation site fidelity, and the abundance of suitable hibernation sites based on surface features to assess whether Massasauga Rattlesnakes are likely to be limited by hibernation site availability on the Bruce Peninsula, Ontario, Canada. We used three years of radio telemetry to locate 46 hibernation sites of 32 individual snakes. Snakes hibernated individually in old root systems, rodent burrows, and rock crevices in forested areas. Hibernation sites could be differentiated from forested areas generally available to snakes but not from locations with holes and crevices in the immediate vicinity of hibernation sites. Few snakes hibernated in the same location in consecutive years, although most (>70%) hibernated within 100 m of their previous location. Overwinter mortality over three years (23%) was similar to mortality during the active season (21%). Our results suggest that Massasauga Rattlesnakes may be limited by the availability of suitable hibernation sites, but sites of similar quality to those used by overwintering snakes are locally abundant. The location of hibernation sites within forests could not be predicted reliably based on surface features. Therefore, efforts to conserve habitat for this threatened species should consider all forested areas on the Bruce Peninsula as potential hibernation habitat.

The Flint Hills region of Kansas is the largest contiguous area of tallgrass prairie remaining today. Historically, the tallgrass prairie burned every 2–3 yr on average, but current land managers have altered burn regimes, resulting in a range of habitats from annually burned to long-term unburned. We used drift fence/funnel trap arrays and coverboards to estimate species richness, evenness, and diversity of herpetofauna within three different burn regimes: annual, 4-yr, and long-term unburned at Konza Prairie Biological Station, Riley County, Kansas. During the spring and fall of 2003–2004, 315 individuals from 20 species were captured across all burn regimes. Herpetofaunal species richness, evenness, and diversity estimates were not different between the three burn treatments. However, because of species-specific responses to individual burn regimes, community composition was significantly different between the habitats (χ² = 158.19, df = 20, P < 0.001). Four species exhibited preferences among burn regimes, which differed significantly from independent assortment, with Eumeces obsoletus and Phrynosoma cornutum preferring annual burn treatments, Scincella lateralis preferring 4-yr burn treatments, and Diadophis punctatus preferring long-term unburned treatments. Species-specific responses were likely because of changes in vegetation structure and microhabitat (temperature and moisture content) created through different frequencies of fire disturbances. Maximizing large-scale herpetofaunal diversity across the Flint Hills' rangelands could be accomplished by creating a large number of small scale habitat types through a mosaic style burning plan.

We evaluated ages of larvae in southern Appalachian populations of the salamanders Gyrinophilus porphyriticus and Pseudotriton ruber by the method of skeletochronology applied to femurs. In P. ruber, the method yielded a strong correlation between snout–vent length and age and provided estimates in agreement with earlier studies of larval growth and age that were based on size-frequency data. However, in G. porphyriticus, the correlation between snout–vent length and age was weak and nonsignificant. This result was in accordance with previous studies that showed that larvae of this species do not sort by size into discrete age classes. The failure of skeletochronology in G. porphyriticus was attributed to either extreme variation in growth rate or to some deficiency of the methodology itself when applied to this species. We suggest that larvae of G. porphyriticus may not develop well-defined annual bone layers because of their adaptation to relatively aseasonal, subterranean microhabitats in headwater springs. In contrast, larvae of P. ruber, although overlapping in macrohabitat with G. porphyriticus, are essentially surface-dwellers that are exposed to the seasonal climatic fluctuations of the region.

Evidence is mounting that warming air and sea temperatures are affecting nesting patterns in oviparous species by causing earlier nesting within seasons. The potential fitness consequences of nesting earlier include extended periods of offspring growth and larger clutch sizes. Additionally, the potential for nesting seasons to last longer exists, possibly allowing species that lay multiple clutches within a season to increase the number of clutches produced. To date, no studies have examined consequences of earlier nesting on duration of nesting season in oviparous vertebrates. We demonstrate that warmer sea surface temperatures are related to earlier nesting in the Loggerhead Seaturtle Caretta caretta, and that this response actually decreases, rather than increases, the length of the nesting season. In recent years (1995–2003), nesting became more evenly distributed throughout the season than in earlier years (1989–1994), and the nesting season decreased by approximately 43 days. Female turtles are unlikely to produce additional clutches within a reproductive season in response to this effect because of physiological constraints, and we cannot rule out the hypothesis that female turtles will lay fewer clutches because of a shortened nesting season, leading to reduced fecundity within seasons.

In turtles with temperature-dependent sex determination (TSD), estradiol applied to eggs incubated at male-producing temperatures produces female hatchlings. In other vertebrate taxa, estradiol administration during embryogenesis often induces only temporary or incomplete feminization, and sensitivity to estradiol can vary among taxonomic families. In the present study, we treated eggs of Kinosternon scorpiodes and Sternotherus odoratus incubated at male-producing temperatures with estradiol-17β and examined reproductive morphology of offspring. Furthermore, to determine whether sex reversal resulting from estradiol application in turtles with TSD is lasting, we maintained juvenile K. scorpiodes in the lab for up to three years prior to dissection. We found normal ovarian morphology and Müllerian duct development in a significantly greater proportion of the hatchling S. odoratus and juvenile K. scorpiodes that had been treated with estradiol during embryogenesis than in the untreated group. Results further suggest that estradiol-induced sex reversal seen in TSD turtles is both permanent and ubiquitous and may shed light on the evolution of sex-determining mechanisms in vertebrates.

Tail autotomy serves as an aid to escape predators in many lizards, but potential costs include loss of fat stores, impaired locomotion, loss of social status, and reduced growth and reproductive output. Two potential costs of tail loss were examined in juvenile skinks, Eumeces fasciatus, through manipulation in a laboratory study. Changes in growth and sprint speed were compared among full autotomy, partial autotomy, and control groups of lizards after these treatments at three weeks of age and up to four weeks later. Full tail autotomy was associated with increased growth in mass during the two weeks posttreatment and increased growth of the tail between two and four weeks posttreatment. No other measures of growth were affected by partial or full tail loss. Immediately following treatments, fully autotomized lizards became significantly slower, with respect to maximum sprint speed, relative to both other groups. However, this effect was gone by four weeks after tail loss.

Amphibians that breed in early spring may encounter considerable variation in ambient temperature. In this study, I investigated how the metabolic rate of male and female Small-Mouthed Salamanders (Ambystoma texanum) is influenced by variation in temperature (5–20°C) during the reproductive season. As expected, both rates of resting oxygen consumption (VO₂) and resting carbon dioxide production (VCO₂) increased with increasing temperature. Both measures of respiration were significantly higher in gravid females than in males and postgravid females across all temperatures. Moreover, the VO₂ of gravid females increased more with increasing temperature than did those of either males or postgravid females. These findings suggest that variation in ambient temperature may have an important influence on the energetic cost of reproductive activity in males and females in this species and in other spring-breeding amphibians.

A largely unresolved ecological issue concerns why normally rare parasites become common within reptile and amphibian populations. We gathered demographic data on incidence of infection and demographic consequences of a normally rare sarcophagid fly parasite (Lepidodexia blakeae) on a population of Green Anole Lizards (Anolis carolinensis). These sarcophagid flies primarily larviposit on adult male Green Anoles during the winter. Sampling by age and sex classes during two years (2003 and 2004) revealed that adult male anoles were infected at an unusually high rate (up to 16%) compared to other populations (only a few documented cases over the past 60 years) and relative to conspecific juveniles and females. Male anoles at Tulane exhibited high mortality compared to other nonparasitized populations, suggesting that parasitism negatively affects survivorship. Although the underlying cause of the high parasitism in the Tulane population remains unclear, several lines of evidence suggest that high and stressful levels of male competition may be a key factor.

The nutritional ecology and digestive physiology of salamanders in the Family Sirenidae remain poorly understood. Although the intestinal contents of these salamanders include herbivorous dietary items, the nutritional significance of such ingested matter is unknown. In this study, we examined gut contents, gastrointestinal structure, and microbial fermentation in wild-caught Greater Sirens (Siren lacertina). Ingested items included aquatic invertebrates, vascular plants, and algae. The guts of these amphibians were not as voluminous or morphologically specialized as in many herbivores, but the posterior intestine was enlarged and exhibited a distinct folding pattern and an ileocolonic valve that may help maintain a symbiotic microbial population. An active microbial fermentation was indicated by relatively high levels of short-chain fatty acids in the medial-posterior and posterior gut regions. This is the first account of gastrointestinal fermentation in the Family Sirenidae and only the second account in the Class Amphibia.

Uma exsul is a restricted, vulnerable, and rare Mexican lizard that occurs only in fine aeolian sand deposits of the central Chihuahuan Desert. The reproductive cycle of this oviparous lizard was determined using monthly samples of both sexes collected throughout 1992 in the dry Laguna de Mayran in southwestern Coahuila, México. Females reached sexual maturity at a smaller snout–vent length (SVL; 60 mm) than males (73 mm). Reproductive activity of both sexes was synchronous and similar to other oviparous lizards. Mating and courtship occurred from March to June. Males exhibit testicular recrudescence during late winter (February and March) and maximum testicular volume occurred during June. The period of maximal testicular volume was positively correlated with increasing ambient temperature. Testis volume began to decrease in July, reaching minimum volume from August to October. Similarly, females began vitellogenesis during March and contained oviductal eggs from April to July. Females on average laid one or two clutches per breeding season. Mean clutch size based on oviductal eggs was 3.0 ± 0.1 SE (range = 3–5). Clutch size was positively correlated with female SVL. Hatchlings occurred during summer and early fall, when most of the annual rainfall occurs. Uma exsul and Mexican Uma paraphygas mature early and are short lived, consistent with an r-selected life-history strategy. In contrast, the North American species Uma scoparia, Uma inornata, and Uma notata exhibit K-selected characteristics.

Eleutherodactylus coqui was accidentally introduced to east Hawaii Island in the late 1980s and has since become established as scattered populations across the island. Mark-recapture study plots indicate that population size remains small for the first year after initial colonization. Plots in heavily forested areas where the Coquí has become well-established yield population estimates of frog density three times the estimates reported from native populations in Puerto Rico. Surveys of the Hilo area using sound pressure level meters found many loud chorusing populations producing sound pressure levels up to 73 dB suggesting that this frog will achieve high densities through broad areas of Hawaiian forest and towns. We suggest that the apparent lack of native or exotic predators in Hawaii and abundance of suitable retreat sites contribute to achievement of unusually high population densities of E. coqui in Hawaii compared with Puerto Rico.

Because polychlorinated biphenyls (PCBs) persist in the environment and are lipophilic they can accumulate in wildlife. Little is known about accumulation or effects of PCBs in anurans; therefore, we chose them for study at a PCB contaminated Superfund site. We wanted to determine which anuran species and life stages were the best indicators of PCB accumulation in outfalls (drainage ditches) flowing from the Paducah Gaseous Diffusion Plant (PGDP), Paducah, Kentucky, and how PCB accumulation might affect individuals. We measured PCBs (Aroclor 1260) in captured adult anurans of various species. A total of 60 adults of six different species were captured among all study sites. Juvenile anurans had greater concentrations of PCBs than adults (P < 0.001); however, there were no differences in PCB accumulation among species in either adults (P = 0.103) or juveniles (P = 0.584). The results of this study indicate that juvenile anurans accumulated greater concentrations of PCBs compared to adults collected from the same stream locations and that juveniles appear to be useful indicators of PCB contamination in aquatic systems. No adverse effects were observed in captured anurans.

Enteric bacterial communities from Southern Toads (Bufo terrestris) and Spring Peepers (Pseudacris crucifer) were quantified during larval development and metamorphosis to examine relationships between development and enteric microflora. Higher levels of enteric Gram-negative bacteria were observed during metamorphosis in each species' intestines. Gut content had no effect on bacterial levels in B. terrestris. Much higher bacterial levels were recorded in smaller metamorphs. The results of this research suggest that enteric microflora may play an ecological role in anuran development and metamorphosis.

We determined the karyotype of Anolis desechensis and compared it with the known karyotypes of other members of the Anolis cristatellus series. The diploid (2N) number of chromosomes of two male A. desechensis was 27, with six pairs of large metacentric macrochromosomes, six pairs of microchromosomes of gradually decreasing size, and sex chromosome heteromorphism (three sex chromosomes, X₁X₂Y). This chromosome complement is identical to that of A. cristatellus and A. scriptus, thus providing additional evidence of a close relationship to these taxa. The evolution of chromosome number within the cristatellus series appears to have involved minimal homoplasy and therefore contains useful phylogenetic information.