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Over the past century, humans have cleared the Earth's forests at an alarming rate and intensity. The majority of global forest cover is categorized as secondary forest, and it is becoming increasingly important to consider secondary forests in addition to old-growth forest in conservation planning for biota. We reviewed the literature to synthesize information on amphibian and reptile communities during secondary forest succession. We summarized literature on mechanisms of community change during forest succession and conducted a meta-analysis to estimate effect sizes for species richness and abundance in human-modified landscapes (agriculture, pasture, and plantation) and old-growth forests compared to regenerating secondary forests. Studies reported strong support for differences in species composition among human-modified landscapes, secondary forest, and old-growth forest as well as species-specific responses to successional forest change. Secondary forest generally had higher species richness and abundance than human-modified landscapes, but lower species richness and abundance than old-growth forests. This result was more pronounced in amphibians than reptiles, and effect size of abundance was more variable than richness among studies. Secondary forests have better conservation value than altered habitats, but they do not necessarily hold the same conservation value for species as old-growth forest. [ABSTRACT FROM AUTHOR]

Eco-evolutionary dynamics occur when ecological change influences evolutionary change (eco-to-evo) and when evolutionary change influences ecological change (evo-to-eco), both on contemporary time scales. Fishes, amphibians, and reptiles have played important roles as study animals in the empirical study and exploration of these dynamics. We suggest that this primacy stems in part from the sweet-spot that many species of fishes, amphibians, and reptiles occupy on the continuum from experimental convenience to ecological importance, as well as on the particular organismal properties that they share, including indeterminate growth and ectothermy. Yet our overall understanding of eco-evolutionary dynamics remains very limited. In the hope of reducing this information gap, the present symposium proceedings include 12 contributions that speak directly to three critical topics in eco-evolutionary dynamics: the role of human influences, constraints and alternatives, and the context dependence of eco-evolutionary dynamics in nature. [ABSTRACT FROM AUTHOR]

The article presents profile of herpetologist Janis Arnold Roze who researched about life and its power. It mentions that Roze along with his brother Jesús Hoyos have collected reptiles and plants on Margarita Island in Venezuela; and wriiting articles on peculiarities of natural history and popular culture of turtles. It also mentions that Roze has worked at the Universidad Central de Venezuela; and has worked in field of biological and human sciences.

Incongruence between morphological and molecular-based phylogenetic hypotheses has been reported across a wide range of taxa. Specifically, morphological and molecular hypotheses of squamate phylogeny have been consistently incongruent and have been notoriously difficult to reconcile. With the ever-rising popular view of the superiority of molecular data over morphological data, studies have been biased toward seeking explanations for homoplasy in the morphological data. We propose considering approaches that do not make a priori assumptions about the superiority of one type of data over another. We present two case studies using the proto-oncogene c-mos, as well as a large multi-locus dataset, to examine apomorphy distributions across hypotheses. This approach reveals novel insights into data incongruence currently plaguing squamate phylogeny, with direct implications for other scenarios of phylogenetic incongruence. [ABSTRACT FROM AUTHOR]

Ichthyology and herpetology remain in need of well-done studies in basic biology and ecology, life history, or natural history for many species. Even for well-studied areas in the United States, the percentage of species for which basic information is lacking or for which better information is needed, based on state or regional faunal books, ranged from about 10 to 35% for fish species, and about 5 to 31% for herps. For Mexico the need was even greater, with the basic biology of approximately 45% of the fish fauna poorly known. Part of the need for better information stems from perceptions by some that basic studies are less desirable than works grounded in theory or modeling. But basic biological information is the foundation for and critical to virtually all syntheses or meta-analyses. Thus, publication of good basic biology in appropriate journals is extremely valuable to one's discipline, and many peer-reviewed journals like Copeia remain amenable to publishing such information. In recent years, graduate students and faculty have been encouraged to publish in high-profile journals, often as judged by 'impact factors.' But impact factors are a poor way to evaluate across disciplines, and the degree to which papers are cited should be given more consideration than the impact factor of any particular journal. Papers in Copeia or similar journals can be and are highly cited, with several in Copeia having been cited 300 to more than 500 times. To the end of high-quality publication of basic information, or its eventual synthesis, suggestions are offered relative to field notes and similar practices. For herpetologists and ichthyologists in mid- to late career, the challenge is to synthesize across one's career, passing to the next generation all that you have learned, by publishing professional books, books for laypersons, or outreach through other media. Contribution to knowledge by publication of basic biological information, and ultimately by synthesizing across one's career, all help meet our obligations to the disciplines that have so shaped our professional lives. [ABSTRACT FROM AUTHOR]

In the majority of frogs, males but not females produce vocalizations to attract mates. Sexual selection can influence the evolution of these vocalizations by modifying the frog's morphology. The larynx is the main organ responsible for sound production; thus, it constitutes a target of selection. The goal of this study was to determine qualitatively and quantitatively the sexual differences in the developmental sequence of larynges of Physalaemus pustulosus ( = Engystomops pustulosus). We examined larynges of individuals ranging from recent metamorphs to adults. We provide quantitative measurements of laryngeal area and volume, vocal cords, and fibrous mass 1 (FM1), as well as qualitative descriptions of the developmental origin of vocal cords and FM1. Larynges of small male and female juveniles (less than 16 mm SVL) are similar, both externally and internally. The area of these larynges is no more than 1 mm2; no vocal cords or FM1 are present in either sex at this developmental stage. In individuals larger than 16 mm SVL, there is a marked divergence in relative size of the larynx between the sexes. The male larynx begins to exhibit a strong positive allometry until it reaches a plateau at 24 mm SVL. Also, at 16 mm SVL, the vocal cords and FM1 appear as distinctive outgrowths on the wall of the arytenoid cartilage in male larynges. Female growth rate of the larynx, however, is constant and exhibits negative allometry throughout ontogeny. Female vocal cords and FM1 are barely distinguishable as adults, and never attain the size and most likely neither the mobility as in the adult male larynx. [ABSTRACT FROM AUTHOR]

This study investigated avian predation on Olive Ridley ( Lepidochelys olivacea) sea turtle eggs and hatchlings at the Ostional (Costa Rica) arribada beach. Our objectives were to identify avian predators and describe their behavior, examine avian foraging opportunities for obtaining eggs and hatchlings, describe different foraging opportunities, and to examine differences in the time hatchlings were exposed on the sand surface to avian predators as a function of time of day, sand temperature, number of hatchlings emerging at one time, and position in the emergence order (early, middle, or late). The timing of nesting and hatchling emergence, length of the incubation period, and heavy rains provided birds with foraging opportunities. Timing is critical because: 1) females nest in every month, but hatchlings require 45-65 days to hatch, thus nesting females dig up nests from previous nestings, 2) heavy rains increase stream flow, causing bank erosion, exposing nests to avian predators, 3) strong tides expose nests to avian predators, 4) hatchlings emerging in the early morning are visible to birds, and 5) length of time for hatchlings to emerge from the nest and reach the water varies among clutches. Black Vultures ( Coragyps atratus), Wood Storks ( Mycteria americana), and Great-tailed Grackles ( Quiscalus mexicanus) accounted for most of the avian predation. Vultures foraged by searching for hatchlings on the surface, for eggs or hatchlings exposed by dogs or people, for clusters of birds around emerging hatchlings, and for opportunities to pirate eggs or hatchlings from other birds. Olive Ridleys avoid predation by predator swamping, nocturnal nesting, and nocturnal emergence of young. Humans decreased predation on hatchlings by removing debris that impedes hatchling movement to the sea, and by keeping predatory birds off the beach during the main early morning hatchling emergence period. [ABSTRACT FROM AUTHOR]

Evidence is accumulating for the ability of animal embryos to hatch early in response to the immediate threat of egg predation. However, early hatching in response to predation is known from only amphibians, fish, and invertebrates. Herein we present the first quantitative evidence for induced early hatching in a reptile. In two laboratory experiments, delicate skink (Lampropholis delicata) embryos responded to a surrogate predator cue--vibrations--by hatching ~3 days earlier than their spontaneously hatching dutchmates. Early hatching embryos were significantly smaller and left more residual yolk in their eggs, however, suggesting a cost to hatching early. Assuming our vibrations were interpreted as an increase in predation risk, skink embryos can thus forego some yolk absorption and growth when threatened by imminent predation. Simulated predation experiments in the field induced hatching in both nest sites (horizontal rock crevices) and in eggs displaced from nest sites. The hatching process was explosive: early hatching embryos hatched in seconds and sprinted from the egg an average of ~40 cm as they hatched. Our results are unusual in demonstrating early hatching in a terrestrial animal with a simple life cycle, and likely extend predation-induced early hatching to reptiles. Early hatching may be widespread in oviparous vertebrates. [ABSTRACT FROM AUTHOR]

The ecological links of aquatic invasive fish and native reptiles are rarely studied. Thus, we analyzed the diet and helminth composition of a recently introduced invasive alien fish (the Rotan, Perccottus glenii) and of two native semi-aquatic snakes (the Dice Snake Natrix tessellata, the Crass Snake N. natrix) in Cranberry Lake, Russia. We also studied diet and helminthes of water frogs (Pelophylax spp.) as a potential mechanism of transmission of parasites. We identified 19 prey taxa and four helminthes for P. glenii, 21 and 24 for Pelophylax spp., and two and 16 for the snakes. The piscivorous N. tessellata has been feeding on P. glenii since its introduction and the subsequent elimination of native fish. Although we did not find P. glenii in the diet of the mainly frog-eating N. natrix, helminth analysis indicated that this snake may prey upon this fish. Both studied snakes contracted the parasitic tapeworm Ophiotaenia europaea from P. glenii. Therefore, the invasive fish and the native snakes demonstrate direct (consumption of fish by snakes) and indirect (transmitting of parasite species) interspecies interactions, which link aquatic and terrestrial habitats. Thus, the invasive fish P. glenii replaced the eliminated native fish in the food web of this lake inhabited by semi-aquatic snakes and became part of the parasite system that includes the native snakes. This is the first evidence of indirect interactions between P. glenii and native reptiles. [ABSTRACT FROM AUTHOR]

Most snakes have the chemosensory ability to identify chemical cues from conspecifics, which is useful in many socia and sexual behaviors. This has been especially well studied in European and North American snake species. In contrast there is a general lack of knowledge on the biology and especially on the use of chemical signals by most Neotropical snake species. Here, we explored the existence of intraspecific recognition by chemical cues in several snake species from Ecuador within the families Boidae (Boa constrictor constrictor, Boa constrictor imperator, Corallus hortulanus, an Epicrates cenchria) and Colubridae (Lampropeltis triangulum micropholis) by using experiments of tongue-flickin discrimination. Results showed that individuals of all species tested showed higher chemosensory responses to odors from conspecific individuals when compared to odors from individuals of other species, suggesting intraspecific chemosensory recognition in these snake species. In contrast, there was not chemosensory recognition between the two subspecies of B. constrictor. We show that some Neotropical snake species are able to use chemical cues of conspecifics in intraspecific recognition, but further studies are needed to analyze the role of chemical signals in their biology and social behavior. [ABSTRACT FROM AUTHOR]

Herbivory is generally thought to be restricted to reptiles with large body sizes that live in warm climates. We show that Liolaemus poecilochromus is primarily herbivorous (>80% plants in diet) even as juveniles, making them the smallest herbivorous reptile known. We detected relatively few differences in diet between the sexes, despite male-biased sexual dimorphism in head and body size. Adults consumed more mites and flowers than juveniles, and we detected a weak ontogenetic shift from omnivory to herbivory that is attributable to the lower volumetric consumption of plants by juvenile males. We discuss the abiotic and biotic conditions that likely selected for herbivory in this and other small-bodied, high-elevation Liolaemus. [ABSTRACT FROM AUTHOR]

Differences in ecological conditions can result in the evolution of dramatic inter-population shifts in whole suites of traits. We studied variation in reproductive output in three lizard populations of the Skyros Wall Lizard (Podarcis guigeae, Lacertidae) endemic to the Skyros Archipelago (Greece), which live under similar climatic conditions but differ in predation pressure and food availability. Based on the "island syndrome" hypothesis, we predicted that females from island populations would produce larger, but fewer offspring. The study populations differ conspicuously in average body size, with males from the satellite Lakonissi and Diavates islets being respectively 20% and 39% larger than males from the main Skyros Island. Lizards from these predator-free islets produced eggs of larger size than the main Skyros population; however, they also produced significantly larger clutches than the Skyros population (2.31±0.83 and 2.73±1.0 vs. 1.97±0.58 eggs). All inter-population differences in clutch size, clutch volume, and egg size were explained by corresponding differences in average body size of the dams, revealing that across all populations, reproductive effort scaled similarly with maternal body size. There was no evidence of trade-offs between egg size and clutch size as generally encountered in many reptile taxa. The occurrence of this unusual pattern of reproductive investment among islet populations of giants is probably best explained by the occurrence of two underlying drivers: first, the substantial marine subsidies by resident seabird colonies and second, the existence of intense cannibalistic behaviors in the form of attacks to the tail and severe intraspecific predation on juveniles. This suggests that subsidies-driven gigantlsm in island endemics may free species from such trade-offs and allow a population to maximize reproductive output in multiple, normally conflicting dimensions. [ABSTRACT FROM AUTHOR]

Hemiergis is a distinctive limb-reduced clade of skinks of the Australian Sphenomorphus group that occur throughout much of southern Australia. Mitochondrial 12S and 16S rRNA gene-sequence data and Bayesian inference (relaxed clock and time-free models) are used to infer the phylogenetic relationships within Hemiergis, as well as test the monophyly of this clade with respect to Glaphyromorphus gracilipes, a southwestern Australia species of the polyphyletic " Glaphyromorphus" assemblage. Hemiergis monophyly is not supported by the mtDNA data, with G. gracilipes being placed as the sister lineage to H. decresiensis sensu lato. Using the Bayes factor, comparison of an alternative hypothesis of Hemiergis monophyly to the preferred hypothesis (i.e., the mtDNA inferred hypothesis with the highest posterior probability) indicates positive support (BF = 3.9-4.1) for the preferred hypothesis demonstrating Hemiergls paraphyly; thus, G. gracilipes is transferred to Hemiergis. Whereas these data strongly support the placement of the two-toed H, quadrilineatum as being closely related to the three- and four-toed populations of H. peronii, the interrelationships among these three limb-reduced phenotypes is unresolved. All other interspecific relationships within Hemiergis are weakly supported by the mtDNA. Within H. decresiensis sensu lato, there is strong support for two divergent lineages that are allopatric. The eastern lineage occurring in Victoria, New South Wales, and extreme southern Queensland is elevated to full species (=H. talbingoensis), with H. decresiensis sensu stricto restricted to the western lineage of South Australia. While many of the interspecific relationships within Hemiergis are weakly supported, these mtDNA data do very strongly favor our preferred hypothesis over an alternative phylogenetic hypothesis implied by a previously proposed parsimonious transformation series of limb reduction; this result implies more independent limb reduction events during the evolution of Hemiergis. [ABSTRACT FROM AUTHOR]

Two fossils from the diverse St Bathans Fauna from Early Miocene sediments in New Zealand are described and identified as from a large, probably terrestrial turtle. They are the first freshwater or terrestrial turtles to have been reported from the Cenozoic of New Zealand. Recent authors have used the absence of turtles and species they considered unlikely to raft to New Zealand to debunk the long held theory that an element of the New Zealand fauna was ancient and vicariant and had evolved on what David Bellamy called Moa's Ark. The discovery that large non-marine turtles were once present in New Zealand adds to a growing and diverse list of terrestrial taxa known from Zealandia shortly after its maximum inundation in the Late Oligocene. Many of these taxa, including a diverse herpetofaunal component, represent lineages endemic to New Zealand and had poor dispersal capabilities, supporting the long held view that a part of the Zealandian fauna was vicariant in origin. [ABSTRACT FROM AUTHOR]

The Massasauga Rattlesnake (Sistrurus catenatus) occurs from extreme southeastern Canada to northern Mexico, and most populations are highly threatened due to habitat loss and fragmentation. Although their range is reduced from historical levels, they may be locally abundant in appropriate habitat. We studied movement patterns, home range and core activity centers, habitat use, and prey abundance in a robust population of Desert Massasauga Rattlesnakes (5. c. edwardsii) in southeastern Colorado by radiotracking 36 snakes over four active seasons (May-October). In the spring, snakes made long-distance directed movements (mean = 1.89 km) from the hibernacula (shortgrass, compacted clay soils) to summer foraging areas (mixed-grass/Sand Sagebrush, sandhills). Summer activity was characterized by short distance non-directional movements, and snakes were most often observed at the base of Sand Sagebrush (Artemisia filifolia). Home ranges and core activity centers were significantly larger for males than for females, but daily movements, total distance moved, and range length did not differ significantly between sexes. Prey base surveys indicated a significantly higher abundance of both rodents and lizards in summer foraging grounds than at hibernation sites. Snakes returned to the hibernaculum area in October and appeared to hibernate individually in rodent burrows. Migration patterns exhibited by S. c. edwardsii are likely resource driven, with the migratory movements observed in the spring resulting in utilization of summer foraging habitat with more abundant prey. Conversely, hibernacula with greater thermal and structural stability in the shortgrass habitat (perhaps due to the compacted clay soils versus loose sandy soils) favor migratory return for torpor in the fall. At present, the main populations in Colorado occur far from developing regions in the state, but due to habitat loss and fragmentation resulting from projected agricultural expansion and urbanization, these populations may be threatened in the future. [ABSTRACT FROM AUTHOR]

The testes of Hemidactylus turcicus are composed of seminiferous tubules lined with continuous germinal epithelia in which multiple germ cell morphologies can be found during the active months of sperm development. Spermatogenesis is quiescent during September, with only spermatogonia A and spermatogonia B present in the seminiferous epithelia and minimal mitotic activity is observed. Recrudescence begins in October and the early stages of spermatogenesis progress through November. The onset of spermiation is observed in December and continues through August with the heaviest sperm release occurring in June and July. Multiple generations of late elongated spermatids are found in association with early mitotic and meiotic cells during the months of December-August. This temporal germ cell development strategy is similar to that described in other squamates and anamniotes and is different from the spatial development exhibited by birds and mammals, in which germ cell populations collectively progress through the stages of spermatogenesis. The reptilian temporal model of germ cell development within a structurally amniotic testis leads to two hypotheses in character evolution: birds and mammals exhibit convergence of germ cell development strategy, or the spatial development strategy is a synapomorphy in amniotes, and reptiles represent an evolutionary reversal to the strategy employed by anamniotes. These findings, along with present and future data, may allow for more concrete phylogenetic analyses by creating more characters for phylogenetic matrices and may prove to be useful in future histopathological studies. [ABSTRACT FROM AUTHOR]

Roads have numerous negative ecological effects on terrestrial fauna, and vehicular mortality can have significant demographic consequences for some species. We studied road mortality of reptiles around Carlyle Lake, Clinton County, Illinois, USA, from April 2000 through November 2002, to assess the impact of vehicular traffic and identify influential factors. Carlyle Lake, a popular tourism/recreation area, is situated in a larger agricultural landscape and is home to the largest Illinois population of the endangered Eastern Massasauga (Sistrurus catenatus). We documented 321 cases of reptile road mortality (84 individuals of six turtle species and 237 individuals of nine snake species) while driving our approx. 46 km study route roundtrip daily. Turtle road mortality was highest in May and June, and positively associated with precipitation and minimum daily temperature. Colubrid snake road mortality was highest in April and October, and positively associated with minimum daily temperature. We recorded 42 cases of road mortality of S. catenatus with the highest number occurring from mid-August to mid-September. Road mortality in S. catenatus was biased toward adult males, which show an increase in movement in August, coinciding with the peak of the mating season and a period of high tourist visitation. The traffic intensity on a road segment did not significantly affect the level of road mortality, but segments through high quality habitats had higher levels of mortality than segments through lower quality habitats. Based on our study on the ecology of S. catenatus, we make recommendations to reduce road mortality that should aid in the conservation of the Carlyle Lake population. [ABSTRACT FROM AUTHOR]

Although recent reports of global amphibian declines have received considerable attention, reptile declines have gone largely unreported. Among reptiles, snakes are particularly difficult to quantitatively sample, and thus, most reports of snake declines are based on qualitative or anecdotal evidence. Recently, several sources have suggested that Eastern Kingsnakes (Lampropeltis getula) have declined over a substantial portion of their range in the southeastern United States, particularly in Florida. However, published evidence for L. getula declines or their potential causes are limited. We monitored the status of a population of L. getula on the U.S. Department of Energy's Savannah River Site (SRS) in Aiken, South Carolina, USA, from 1975 to 2006. Herpetofaunal populations on the Savannah River Site have been protected from the pressures of collecting and development since 1951 due to site access restrictions. Here, we document a decline in both abundance and body condition of L. getula inhabiting the vicinity of a large isolated wetland over the past three decades. Because this L. getula population was protected from anthropogenic habitat degradation, collection, and road mortality, we are able to exclude these factors as possible causes of the documented decline. Although the definitive cause of the decline remains enigmatic, natural succession of the surrounding uplands, periodic extreme droughts, shifts in community composition (e.g., increased Agkistrodon piscivorus abundance), introduced fire ants, or disease are all potential contributors to the decline. [ABSTRACT FROM AUTHOR]

Skeletochronology is the most commonly used tool for evaluating the age of amphibians and reptiles. However, the accuracy of skeletochronology is questionable because few studies have utilized individuals of known age to calibrate their results. In this study, the accuracy of skeletochronology was assessed using individual Arizona Tiger Salamanders (Ambystoma tigrinum nebulosum) that were of known ages that varied from 2-15 years. Cross-sections of salamander toes were analyzed to compare the number of LAG (lines of arrested growth) to the actual age of known cohorts. Our results suggest that skeletochronology was an inaccurate tool for estimating age in this population of A. tigrinum nebulosum because it grossly underestimated age. The high intensity of endosteal resorption coupled with rapprochement of the most peripheral LAG may have produced these results. Our research indicates that skeletochronological studies that do not use individuals of known age for calibration may underestimate age. [ABSTRACT FROM AUTHOR]

Kernel home-range estimators are becoming more widely used to determine the home-range size for herpetofauna, despite the problems associated with selecting the appropriate smoothing factor. We used simulations to demonstrate the inconsistency of kernel estimators at determining the home-range size of random distributions. Furthermore, we used the positions of ten adult male Lampropeltis triangulum radio-tracked over two full active seasons (2003 and 2004) to demonstrate that the size of the home range increases significantly with an increase in the smoothing factor. The degree of increase, however, was not consistent between individuals. In addition, using least-squares cross-validation to select the smoothing factor produced a wide range of values for different individuals. Because of these inconsistencies, we suggest using the minimum convex polygon (MCP) method to calculate home-range size in studies of herpetofauna. When studying habitat use, however, we suggest using the MCP as the area of the home range and adjusting the smoothing factor until the area of the 95% kernel equals the area of the MCP. This provides an objective method for selecting the smoothing factor. [ABSTRACT FROM AUTHOR]

Despite its use as a diagnostic taxonomic feature, the occurrence and distribution of plicidentine in the teeth of squamate reptiles is unclear. This appears to be due to several factors: the various kinds of folding, wrinkling, and striation that occur within different dental tissues; difficulty of interpreting conditions in poorly preserved extinct taxa; and incomplete knowledge of tooth development. We investigated tooth development and morphology in extant and fossil squamate reptiles using skeletal preparations, histological sections, and CT-scanning data. Among squamates, we found plicidentine only in the teeth of varanoid lizards and note that much more anatomical complexity exists than previously thought in the dental and attachment tissues of these groups. Degree of development of plicidentine is variable within varanoids, with the strongest development occurring in some species of Varanus. In contrast to some reports, we found no evidence for the occurrence of plicidentine in the teeth of mosasauroid lizards or snakes. Some mosasaurs exhibit raised ridges on the enamel surface that extend from the base to the tip of the tooth, as well as occasional striation of the tooth bases built from bone of attachment; neither of these features is considered homologous to plicidentine infolding. Some snakes exhibit weak wrinkling of the tooth base that corresponds closely to the pattern of wrinkling in the overlying bone of attachment. This condition occurs infrequently in snakes, and details of tooth development anti attachment also do not support its homology with plicidentine. Our results indicate that plicidentine is best interpreted as a synapomorplay of Varanoidea. [ABSTRACT FROM AUTHOR]

Turtles are in decline world-wide, and few studies have collected the long-term, age-specific demographic data needed to identify species-specific life history stages critical to population viability and conservation. Here I report estimates of birth and death rates, survivorship, and longevity of Spotted Turtles (Clemmys guttata) using modified logarithmic decay equations and 24 years of mark-recapture data collected from a population at the northern extreme of the species' range. The recruitment rate was more than twice the mortality rate. Spotted Turtle survivorship and longevity estimates are among the highest values reported for any animal species, and females are significantly more long-lived than males. Minimum annual adult female survivorship is 96.5%, maximum longevity is 110 years, and age at maturity is 12 years. Minimum male survivorship is 94.2%, maximum longevity is 65 years, and age at maturity is 11 years. This ongoing study is the longest-running on Spotted Turtles, yet insufficient age-specific data have been gathered to construct a life table, particularly because egg and hatchling survival rates remain unknown; future work should specifically focus on gathering such data. The results of the current study have important management implications when considering which life history stages to protect for maintenance of population viability of long-lived vertebrates. [ABSTRACT FROM AUTHOR]

Studies of ecological energetics in chelonians are rare. Here, we report the first measurements of daily energy expenditure (DEE) and water influx rates (Wigs) in free-ranging adult Gopher Tortoises (Gopherus polyphemus). We used the doubly labeled water (DLW) method to measure DEE in six adult tortoises during the non-breeding season in south-central Mississippi, USA. Tortoise DEE ranged from 76.7-187.5 kJ/day and WIR ranged from 30.6-93.1 ml H2O/day. Daily energy expenditure did not differ between the sexes, but DEE was positively related to body mass. Water influx rates varied with the interaction of sex and body mass. We used a log/log regression model to assess the allometric relationship between DEE and body mass for Gopher Tortoises, Desert Tortoises (Gophents agassizii), and Box Turtles (Terrapene carolina), the only chelonians for which DEE has been measured. The slope of this allometric model (0.626) was less than that previously calculated for herbivorous reptiles (0.813), suggesting that chelonians may expend energy at a slower rate per unit of body mass compared to other herbivorous reptiles. We used retrospective power analyses and data from the DLW isotope analyses to develop guidelines for sample sizes and duration of measurement intervals, respectively, for larger-scale energetic studies in this species. [ABSTRACT FROM AUTHOR]

Studies on reproductive biology of individual species provide data necessary for testing hypotheses that seek to explain the diversity of life histories observed in squamate reptiles. The reproductive cycle of Phyllodactylus lanei at Chamela Jalisco, Mexico was aseasonal and varied among months and between sexes. Males and females reached sexual maturity at 52.0 and 49.0 mm snout-vent length (SVL), respectively. Males and females were reproductively active throughout the year, but a distinct cycle was evident. Testes reached maximal size from August to March and began to decrease in size in April, reaching minimum size in July. Gonadal volume in females was greatest from January-April coincident with maximal egg production. However, some females were found with eggs in nine of the 12 months, indicating an extended egg-laying season. Some females (7.6%) contained eggs and vitellogenic follicles simultaneously. Females were capable of producing at least three clutches of two eggs during the reproductive season. The testicular cycle was correlated with photoperiod but not rainfall or temperature. The female gonadal cycle was correlated with mean monthly temperatures but not photoperiod or rainfall. Monthly production of oviductal eggs was correlated with monthly mean temperatures but not photoperiod or rainfall. Egg mass was significantly correlated with female mass but not with SVL. This study provides another example of a gecko species in which the reproductive season is extended, females reproduce repeatedly, but egg production is greatest during the dry season. [ABSTRACT FROM AUTHOR]

In the last two centuries, European fire suppression practices have produced increases in vegetation density and canopy cover in many landscapes. Potentially, increases in canopy cover could negatively affect small populations of nocturnal reptiles that use sun-exposed shelters for diurnal thermoregulation. We hypothesized that vegetation encroachment over rock outcrops might partly explain the recent decline of Australia's most endangered snake, the Broad-headed Snake Hoplocephalus bungaroides. To test this hypothesis, we carried out a field study in Morton National Park, southeastern Australia. We removed overhanging vegetation from above shaded rocks and compared their subsequent usage by reptiles to control (shaded) rocks. In spring, one year after canopy removal, experimental rocks were 10.3 C hotter than control rocks and were used as diurnal retreat sites by three species of reptiles, including the endangered Broad-headed Snake and its prey (Velvet Gecko, Oedura lesueurii). By contrast, no reptiles used control rocks as diurnal retreat sites. Our results show that modest canopy removal (∼15% increase in canopy openness) can restore habitat quality for nocturnal reptiles. Future studies are needed to examine whether controlled burns can maintain an open canopy above sandstone rock outcrops. However, until effective fire management measures are in place, sapling removal from overgrown rock outcrops could help to protect small populations of endangered reptiles. [ABSTRACT FROM AUTHOR]

The comparative diet and body size of the Four-Lined Snake (Elaphe quatuorlineata), one of the largest and more vulnerable species of snakes in Mediterranean central Italy, were studied in five different habitats. Data given here collated both literature and original data. Overall, females were significantly larger than males but the strength of these differences varied considerably with sample size. Overall, small mammals (almost exclusively rodents) accounted for the main part of the diet (66.7%), followed by birds and their eggs (mainly Passeriformes; 26.4%), and by lizards (6.9%), although the number of eggs in the diet was probably greatly underestimated. In qualitative terms, both sexes fed on the same prey types, but, quantitatively, males and females differed significantly in terms of prey composition; females fed on more birds and fewer lizards than males. Rodents were the most important prey source in most habitat types, although birds were preyed upon slightly more frequently in the wet habitat than rodents, which, nonetheless, still represented a important prey source. Four-Lined Snakes started feeding in early April and continued feeding until early November. The monthly frequency of occurrence of birds in snake stomachs differed significantly from that of small mammals; birds were taken almost exclusively in April and May (and mainly by females), and small mammals were taken all throughout the annual feeding cycle of snakes. [ABSTRACT FROM AUTHOR]

The relationship between egg size and composition (relative amounts of lipid, protein, and water) can play an important role in determining neonate size, quality, or the amount of post-hatching care observed in many reptiles. We evaluated the relationship among egg wet mass, non-polar lipid mass, water content, shell dry mass, and lean dry mass within and among seven clutches of the Diamondback Terrapin, Malaclemys terrapin, from Chesapeake Bay. Egg size varied considerably among clutches, but was relatively uniform within clutches. Non-polar lipid mass, lean dry mass, and water content correlated positively with egg wet mass indicating that larger eggs contain a proportionally greater amount of these components. There was no relationship between egg wet mass and shell dry mass. Clutches had similar, positive slopes but different intercepts in the relationships between lean dry mass and lipid mass and between water content and total dry mass. Thus, clutches differed in the relative proportions of resources but had similar allocation patterns of egg components. Our data cannot resolve whether these effects are due to differences in resource availability or differences in the physiological mechanisms involved in egg provisioning. [ABSTRACT FROM AUTHOR]

The ability to detect and follow prey chemical trails is important for actively foraging nocturnal snakes. We investigated whether a nocturnal, ophiophagous (snake-eating) predator, the Bandy-Bandy (Vermicella annulata) can detect and follow blindsnake chemical trails. Adult Bandy-Bandys were offered the choice between control traits (distilled water) and chemical trails from three sympatric squamate species. Bandy-Bandys ignored distilled water trails and the trails of the burrowing Yellow-Bellied Three-Toed Skink (Saiphos equalis) and the nocturnal Golden Crowned Snake (Cacophis squamulosus). In contrast, all of the Bandy-Bandys followed chemical trails from the Blackish Blindsnake (Ramphotyphlops nigrescens), and three snakes followed the blindsnake trails along their entire length (mean distance followed = 0.93 m, range 0.2-1.4 m). Our results suggest Bandy-Bandys use chemical cues to locate blindsnakes but do not respond to chemical trails of other sympatric squamate species. [ABSTRACT FROM AUTHOR]

Theoretical and empirical studies of habitat selection suggest that reptiles should use "fixed" structural features (perch diameter, vegetation) or light intensity (sun and shade) to select thermally suitable microhabitats. But how do nocturnal species select thermally suitable diurnal retreat sites at night in the absence of visual cues? To investigate this question, we studied habitat selection by two sympatric nocturnal snakes, the endangered Broad-Headed Snake Hoplocephalus bungaroides and the common Small-Eyed Snake Cryptophis nigrescens. In the field, we investigated whether snakes selected diurnal retreat sites nonrandomly with respect to vegetation structure and rock temperature. In the laboratory, we offered snakes a choice between rocks with different crevice sizes, temperatures, and degree of shading. In the field, rocks used by snakes received significantly higher levels of incident radiation intensity (and therefore had higher temperatures) than random rocks but had similar levels of canopy cover. This apparent paradox reflects differences in the position of canopy gaps relative to the path of the sun, the most important determinant of a rock's diurnal temperature profile. In the laboratory, snakes chose rocks with narrow crevices but did not discriminate between shaded and exposed rocks. Snakes consistently chose hot rocks over cold rocks, even though the nocturnal temperature difference between the two retreat sites was less than 4 C. Our results show that these nocturnal snakes use a fixed structural cue (crevice size) to select potential retreat sites but then use a temporally variable cue (substrate temperature) to choose among potential retreat sites. [ABSTRACT FROM AUTHOR]

The reptile immune response is performed by a well-developed immune system whose leukocytes have been characterized as lymphocytes, monocytes and granulocytes. A main characteristic of the reptile immune system is the effect of the seasonal cycle on its histology and function, as has been reported in the turtle Mauremys caspica. In the present study, we have assessed the presence of lymphocytes in the " main lymphoid tissues (blood, spleen, and thymus) searching for putative seasonal variations and sex-associated differences in lymphoid distribution. Our results show that lymphocytes are the most commonly observed leukocyte subpopulation in blood. The highest percentages of blood lymphocytes were obtained in spring. Lymphoid tissues showed higher proportions of lymphocytes in spring and summer. Finally, females showed higher lymphocyte proportions than males in the spleen during spring and in the thymus during summer. Summarizing, the lymphoid redistribution of M. caspica is affected by the seasonal cycle. The major proportion of lymphocytes was obtained in spring and summer; the seasonal periods when these turtles are more active, and the risk of infections is higher. [ABSTRACT FROM AUTHOR]

Coordinated terrestrial movement has not previously been reported in crocodilians. However, between 1989 and 1999, 94% of 525 Caiman crocodilus yacare found on land in the Pantanal were in coordinated groups (n = 73) walking head to tail and forming nearly straight lines. Caimans left pools and initiated terrestrial movements spontaneously and in response to disturbance by researchers and hunters. The sex ratio of the groups was biased toward males (0.8 ± or 0.24) and was similar to that found in aquatic habitats in the study area. However, two groups consisted only of females. When caimans left pools subjected to disturbances, such as hunting and capture for research, they walked head to tail in lines. Caimans that left pools in response to disturbance buried in mud near pools or in leaf litter in forest. [ABSTRACT FROM AUTHOR]

Presents the biography of biologist Garth Leon Underwood. Personal background; Experiences during the World War II; Contributions to reptilian morphology and systematics.

The sand vipers of the genus Cerastes vertically burrow into the soft sand of the Saharan desert. The mechanics of vertical burrowing in Cerastes cerastes and Cerastes vipera were explored using a combination of morphology, videography, radiography, and experimental manipulation. The results suggest that the key to vertical burrowing is localized unilateral rib abduction. The ribs terminate in expanded calcified costal cartilages, which, when abducted, aid in scraping sand from below the snake and transporting it laterally. The transport of the sand is enhanced by long-axis torsion of the vertebral column. The specialized lateral scales of Cerastes do not appear to function in vertical burrowing. [ABSTRACT FROM AUTHOR]

To test functional hypotheses about home-range variation, it is necessary to compare the fitness of individuals whose home ranges are characterized by measurable differences in vital resources such as mates and food. In the present study, we compare measures of reproductive success of male lizards estimated from field observational data with results from DNA fingerprinting of the same individuals. Observational data included both male and female home-range overlap and proximity of actual sightings. Because home ranges can function for access to mates, and males with larger home ranges earl overlap a greater number of females, we tested the hypothesis that males with larger home ranges have higher reproductive success. We also tested to see whether females were most likely to mate with males that overlapped their own home range. We found a positive correlation between male home-range area and the number of females overlapped by a male. Male reproductive success was not significantly correlated with home-range area but was positively associated with the number of females overlapped by a male home range, even after the effect of body size had been statistically removed. Despite this relationship, only about 40% of our observational estimates of reproductive success were confirmed by DNA fingerprinting in this population. Thus, many females had mates whose home ranges did not overlap their own, and proximity of a male to a particular female did not accurately predict paternity. [ABSTRACT FROM AUTHOR]

The current literature reports divergent conclusions on the patterns of body size change in island snakes. I reviewed body size data in the published literature and tested the effects of island biogeographic variables on such changes. I found that none of the physiographic variables (island area, island age, distance to mainland, and latitude) was important in determining changes in size of island snakes. Additionally, a current hypothesis of phylogenetic history had no effect on changes in body size. Rather, the proportional change in body size of island snakes was bimodal, consistent with a diet alteration hypothesis that suggests that snake body size is principally influenced by prey size and that island snakes encounter prey that are larger or smaller in size compared with those on the mainland. Also, snakes that became small on islands did so to a relatively greater degree than those that became large. Ontogenetic changes in foraging strategies appeared to explain this pattern. The distribution of gigantic and dwarf snake populations on islands differed significantly between the families Viperidae and Colubridae. The foraging style of colubrids, specifically nest-robbing behavior, may predispose these species to become larger on islands. Numerous colubrid (and one elapid) species attain their largest sizes on islands that also support nesting seabirds, whereas dwarfed populations consume mainly squamates. [ABSTRACT FROM AUTHOR]

Reports on the posters published by the Maine Department of Inland Fisheries and Wildlife illustrating the state's amphibians, turtles and reptiles as of September 2004. Number of posters published; Animals included in the posters.

Reports on the research grant awarded to the Sternberg Museum of Natural History of Fort Hays State University to conduct a statewide inventory of amphibians, reptiles and turtles in Kansas. Objectives of the Kansas Department of Wildlife and Parks in funding the research; Goals of the Sternberg Museum for the project.