Frogs are often rare or absent from intensively farmed areas. Here we explore the possibility that the landscape and the quality of the terrestrial habitat are unsuitable for these populations. Spawn of Rana arvalis and R. temporaria was introduced into ponds in a south Swedish agricultural landscape in 2003 (eight ponds) and 2004 (ten ponds). Metamorphs emerged front nine (R. a.) and 12 (R. t.) of these. In years following the introduction, spawn was found in five (R. a.) and eight (R. t.) of these 18 ponds. The number of spawn clumps peaked two years after the introduction. Three or four years after the introduction, breeding persisted in only two of the ponds (where both species were breeding). One year later also these populations had also become extinct. In control ponds (ponds within 750 in of the introduction ponds), spawn of R. temporaria was occasionally found but there was no trend, nor any temporal peak in frequency or quantity of spawn in these ponds. There were calling males of both species already one year after the introduction at a few ponds, indicating an unusually early maturation for sonic individuals. We suggest that the terrestrial habitat ill this region is not suitable for the continued presence of populations of R. arvalis and R. temporaria. This may be related to the habitat per se or to the isolation of the populations. (C) Koninklijke Brill NV, Leiden, 2009
I present an up-to-date annotated list of the herpetofauna of Martinique, and try to explain the causes responsible for the eradication of species such as Leptodactylus fallax , Boa sp. and Leiocephalus herminieri . Mabuya mabouya and Liophis cursor have not been seen for decades and may have been extirpated. It cannot be established that the mongoose was responsible; Didelphis marsupialis , of recent introduction, may have played an important role. Introduced and invasive species are numerous in Martinique: Chaunus marinus , Scinax ruber , Eleutherodactylus johnstonei , Gymnophthalmus underwoodi , Iguana iguana , Gekko gecko , Hemidactylus mabouia , without considering escaped pets and the dubious case of Allobates chalcopis as an endemic species. I also present the restoration plan for Iguana delicatissima in the French West Indies and the conservation work for this species in Martinique; increase of nesting areas, translocation, creation of numerous protected areas, and control of I. iguana . Of a total of 13 endemic and indigenous species from Martinique, three are definitely and a further two are probably eradicated. Including Guadeloupe, the French West Indies have the highest loss of herpetological biodiversity among all the islands in the West Indies.
Key data Hemidactylus frenatus; Gekkonidae; Common House Gecko; Ecuador; Provincias Esmeraldas and Manabi; population; San Lorenzo & Pedernales. UTA R-55986–88 & DHMECN 04606; verified by Carl J. Franklin, Amphibian and Reptile Diversity Research Center, University of Texas at Arlington, and Cecilia Tobar, Division de Herpetologia, Museo Ecuatoriano de Ciencias Naturales, Quito, Ecuador. © Koninklijke Brill NV, Leiden, 2009
Research aimed at determining the extent of terrestrial habitat use by amphibians has been impeded by the difficulties associated with relocating and identifying individuals in the field. Recent studies have used fluorescent powder pigments as a method for tracking short-term terrestrial movements of frogs and salamanders. In a laboratory experiment we found no effect of repeated exposure to two different types of fluorescent powder on mass or survival of terrestrial juvenile and adult Eastern red-spotted newts (Notophthalmus viridescens). We provide further evidence that fluorescent powder tracking is safe for use on amphibians and may be an effective tool for studying terrestrial habitat use. (C) Koninklijke Brill NV, Leiden, 2009
At least 14 species of geckos are utilized as ingredients in the pharmacopia of traditional medicine systems around the world. Chinese Traditional Medicine uses two types of geckos, large tokay geckos (Gekko gecko) and small geckos (Gekko spp., Hemidactylus spp.) to treat a diversity of ailments including asthma, tuberculosis, diabetes and cancer, and current research in China focuses on the identification of active ingredients in geckos and the verification of their efficacy. The actual number of species involved in the Chinese Traditional Medicine trade may be higher than currently realized due to the fraudulent sale of counterfeit geckos and accidental misidentification. The potential pool of species includes at least 37 species from throughout the broad area in which geckos and other wildlife are collected for use in China. Although powders and tablets pose difficulties for identification, the whole dried form in which geckos are often sold permits the identification of most species. A key is provided to the 12 species of geckos most likely to be encountered in the trade of Asian traditional medicine.
The Mediterranean house gecko (Hemidactylus turcicus) is native to countries surrounding the Mediterranean and extends east to India and Somalia (Conant and Collins, 1998). However, H. turcicus has spread to several New World countries including Cuba, Mexico, Puerto Rico, Panama, and the United States. The first verified report of H. turcicus in the United States is known from Key West, Florida in 1915, with other notable introductions documented in Arizona, California, Louisiana, Alabama, Texas, and other areas of Florida (Lever, 2003). Spread of this species has since been documented in many additional states (Livo et al., 1998; Hare, 2006; Kleopfer et al., 2006; Reed et al., 2006; NatureServe, 2008; Platt et al., 2008). Human-mediated dispersal is thought to be the major cause of this species’ dramatic range expansion (Lever, 2003), and Locey and Stone (2006) suggested that dispersal ability is limited and jump dispersal events are the major mode of expansion. Climate is thought to be a major factor preventing the northward spread of this species (Meshaka et al., 2006). However, cold climates are circumvented through exploitation of heated buildings, demonstrated by gecko presence in Colorado, South Dakota, and Maryland (Livo et al., 1998; NatureServe, 2008; Platt et al., 2008). Hemidactylus turcicus has been recorded throughout much of East and South Texas, but notable gaps exist in its distribution, such as the apparent absence from the panhandle with the exception of Lubbock County (Dixon, 2000; Jadin and Coleman, 2007). Approximately 28 counties in Central Texas lack a record
Although the American alligator has been well-studied in coastal marshes and large reservoirs, very few studies have taken place in the isolated, seasonal wetlands that occur within the inland portion of the alligator’s range. Understanding alligator populations in these systems is important because, although they are subject to the same management strategies and regulations as their more well-studied counterparts, they may have markedly different population dynamics and densities. Additionally, understanding patterns of alligator presence in isolated, seasonal wetlands is important to understanding how alligators may affect these critical habitats as ecosystem engineers. However, survey methods designed for large, open water systems may not work in these small, vegetated wetlands, and their efficacy in this habitat has yet to be documented. We conducted eyeshine surveys for alligators along walking transects through isolated, seasonal wetlands in southwest Georgia. We used a double-observer method with a Huggins closed capture analysis to determine the detection probability of this method, to model the effects of observer and wetland type on that parameter and to estimate abundance. We found that detection probability for eyeshine surveys under the best-supported model was 57%, between 2 and 5 times higher than documented in other habitats. We then compared eyeshine surveys with systematic trapping to ascertain which components of the population were more likely to be detected by each method. Both methods were effective in detecting a range of size classes in the wetlands; however, the two methods were most effective when used in concert. Wildlife biologists studying population trends and establishing harvest quotas can use this information to design surveys in the inland portion of the alligator’s range. © Koninklijke Brill NV, Leiden, 2009
Forensic work relating to reptiles and amphibians often necessitates a visit to the scene of an alleged crime in order to assess the site and to gather evidence. This may be part of law enforcement investigation or in order to assist, whether called by prosecution or defence, in a court case. When wildlife crime is suspected, fieldwork may be needed; this can present particular challenges and may necessitate the use of portable equipment and the performance of clinical, post-mortem and laboratory investigations under improvised conditions.
Measures of fluctuating asymmetry (FA) have been used to assess the significance of stress in amphibian populations. When animals with bilateral body plans are challenged by environmental stressors, departures from bilateral symmetry can emerge during development. The tendency for FA to develop has been linked to greater susceptibility to pathogens in many organisms. In our study, newts (Notophthalmus viridescens) infected with Ichthyophonus-sp. exhibited greater size-corrected FA of the hind limbs than uninfected animals from the same population. Among infected animals, however, the intensity of infection and the extent of hind limb asymmetry were not correlated, suggesting that asymmetry did not arise following infection, but rather that newts having greater FA may have been more susceptible to infection as a result of the same stresses that produced the increase in FA. There was no relationship between dorsal spot pattern FA and infection status or hind limb FA. We suggest that spot pattern may be less canalized than hind limb development. Newts are widely distributed and important components of freshwater communities in eastern North America and, thus, any change in their vitality may affect the composition of those communities. Analyses of hind limb FA may be a useful and non-invasive tool for identifying potentially vulnerable amphibian
The herpetofauna of the Dominican Republic consists of 39 frogs (two of which are introduced), 110 squamates (one possibly extinct and three or four introduced), one crocodilian, three turtles (one introduced), plus four species of sea turtles. Reflecting the recent "Global Amphibian Assessment," 32 of 37 (86%) native species of amphibians are included on the IUCN Red List. Reptilian species given formal recognition as being in need of protection include the sea turtles (listed in CITES appendices and the IUCN Red List), the two native species of pond turtles (Trachemys spp.; IUCN, although one as being at "lower risk" of extinction), both species of rock iguanas (Cyclura spp.; CITES and IUCN), two giant galliwasps (Celestus spp., IUCN), three boids (Epicrates spp., CITES), a ground boa (Tropidophis haetianus, CITES), and the American crocodile (Crocodylus acutus; CITES and IUCN). However, at least some additional squamate species appear to meet criteria for inclusion on the IUCN Red List. Four factors largely responsible for the status of these species are: (1) small ranges, habitat specialization, and encroachment by human activities (many amphibians); (2) large size and economic value (turtles, iguanas, crocodile); (3) persecution by people who fear them (galliwasps and snakes); and (4) diurnally active, terrestrial, and vulnerable to predation by mongooses and other introduced mammalian predators (some snakes, Mabuya). Although protection for a few species and for national parks in critical habitats is legislated, enforcement is sporadic and threats, mostly associated with exploitation and development, remain. Specific recommendations for the conservation of the herpetofauna are listed.
Although diamondback terrapins appear to be declining throughout much of their geographic range, more information is required to evaluate population trends. Unfortunately, sampling terrapin populations is both time and labor intensive. We initiated studies to examine the efficacy of using head counts in tidal creeks as a rapid-assessment technique for monitoring terrapin populations. From 2005 to 2007, we conducted headcount surveys in conjunction with regular aquatic sampling. Head-count surveys consisted of recording the number of terrapins we observed from a boat going up (run 1) and down (run 2) tidal creeks. These surveys were conducted before aquatic sampling (i.e., low tide) as well as other times (e.g., high tide). We found the strongest positive relationship between the number of terrapins observed in run 1 combined with run 2 and the number of terrapins captured (R 2 = 0.538). We examined the effects of variables such as day of year, time of day, cloud cover, and creek location on the number of heads seen. Such models will allow effective monitoring of terrapin population trends and improve implementation of appropriate conservation measures. We recommend a refinement of head-count surveys and the involvement of citizen scientists to aid in the establishment of a range-wide monitoring program that will greatly increase survey effort while saving time and money. © Koninklijke Brill NV, Leiden, 2009
While techniques for sampling pond-breeding amphibians are relatively well-established, comparable methods for stream amphibians are still being developed. Uncertainty about sampling techniques is particularly acute for approaches that involve multiple observers. I evaluated three techniques for sampling stream salamanders with multiple observers—time-constrained surveys, leaf-litter bags, and controlled-cobble added to the stream. I tested for differences among techniques, differences among habitats, and technique by habitat interactions. I also asked whether coefficients of variation across observers and sample dates differed among methods and habitats. For all species and life-stages, time-constrained surveys produced higher counts of stream salamanders and greater richness estimates than did leaf-litter bags or controlled-cobble surveys. However, interactions between techniques and habitat were never significant, indicating that all the methods detected similar patterns in counts among stream habitats. Coefficients of variation in single-species counts tended to be higher for time-constrained surveys, whereas CVs for species richness were significantly lower for time-constrained surveys. Overall, these results suggest that: (1) time-constrained surveys for stream salamanders work surprisingly well even with multiple observers, (2) leaf-litter bags may be quite useful for single-species studies, but are less effective for multi-species sampling, and (3) controlled-cobble added to streams is not particularly effective for sampling salamanders in rocky streams.
Methods for attaching radio transmitters to rock iguanas (genus Cyclura ) are described and compared based on signal range, longevity of attachment, and potential disturbance to animal behavior or health. Case studies are described for all instances of internal implantation, ingestion, and external attachment of transmitters for which data are available. Signal range did not differ dramatically between attachment methods, but did differ between transmitter models and habitats in which iguanas were tracked. Only transmitters with coiled antennas showed a dramatic reduction in signal range. Longevity of transmitter attachment varied greatly among attachment methods, and was greatest for implantation, least for ingestion, and intermediate for external methods. Internal placement of transmitters via ingestion or implantation was advantageous in having no external apparatus to snag on vegetation or rocks. However, ingestion yielded less than one week of data, and implantation required costly, potentially stressful surgery. External attachment methods, including suturing of transmitters, mounting with adhesive, and harnesses or collars with breakaway mechanisms, entailed low cost and low risk, but were less reliable for long-term attachment. Harnesses or belts that lacked breakaway mechanisms entailed higher risk, because iguanas may suffer injury or death if not monitored frequently and recaptured for removal of attachment devices. In many studies, iguanas successfully mated, nested, and appeared to behave normally with transmitters attached by various methods. However, further research is needed to determine how different attachment methods affect the health, behavior, and survivorship of iguanas, particularly in smaller species and juveniles, which are more susceptible to predation.
Amphibians can be very difficult to mark because of their extraordinary powers of regeneration. Although many amphibian marking techniques have been developed, few meet the rigorous assumptions of capture-mark-recapture models. Also, excessive toe-clipping may affect frog survivorship adversely. We tested the efficacy of a new hybrid marking technique (VIE-C) that combines Visible Implant Elastomer (VIE) and toe-clipping on four species of treefrogs in West-Central Florida. Of the 840 treefrogs recaptured over a 15-month period, only one mark was unreadable. A significantly higher percentage of VIE marks (80%) than toe-clips (55%) remained viable for the duration of the study. On average, toe-clips remained readable for 100 days, and VIE marks remained readable for 112 days. There were no significant species differences in the length of time that either type of mark lasted. The hybrid VIE-C method represents an improvement over either method used alone, but the VIE mark will be more helpful in correctly reading and clarifying toe-clipping errors than will toe-clips be helpful in reading and clarifying VIE marks. (C) Koninklijke Brill NV, Leiden, 2009
Eleutherodactylus lentus, thought to be endemic to the US Virgin Islands, is now found on Jost Van Dyke in the nearby British Virgin Islands, where previous surveys have failed to note it. This poses an unusual conundrum. If the new record represents human-aided dispersal, then control actions may be appropriate, even though the species is categorized as at risk in its native range. However, it is possible that this population is native to Jost Van Dyke, and was not previously recorded because of methodological issues. In that case, protection would be warranted. Interviews with researchers and locals suggest the former scenario is more likely. (C) Koninklijke Brill NV, Leiden, 2009
Anolis aeneus and A. trinitatis were introduced to Trinidad before 1900, and A. extremus was a more recent introduction in the 1960s-1980s. The three species are of similar body size, and A. aeneus and A. trinitatis are known to hybridize in Trinidad. Detailed studies from the late 1960s indicated that A. aeneus was widespread but A. trinitatis was localized and apparently in decline due to hybridization pressure. In this study we examined all the known sites of A. trinitatis (and A. extremus ) in Trinidad, and many new sites. A. trinitatis remained abundant in and to the east of San Fernando in southern Trinidad. Two small populations remained in northern Trinidad, at one site in Port of Spain and at St Augustine, but A. trinitatis no longer occurred at most former sites there. A. trinitatis and A. aeneus had high niche overlap (0.99 or greater) for the three dimensions examined (substrate type and perch height and diameter). Both species were apparently still spreading into vacant habitats east of San Fernando. Of 12 sites from which A. trinitatis had disappeared, four had no anoles, four had sparse populations of A. aeneus , and only four had dense populations of A. aeneus . This pattern suggests that the decline of A. trinitatis is not related to hybridization with or competition from A. aeneus . An alternative hypothesis is presented, that A. trinitatis requires more vegetated habitats, which have been increasingly lost during urban development especially in northern Trinidad. A. extremus is apparently now extinct in Trinidad.
As the study of bone disease in recent and fossil amphibians and reptiles has evolved from observational speculation to analysis of testable hypotheses, so too has recognition of its contribution to our understanding of diseases and organisms. Given the development of a 'library' of macroscopic osseous manifestations of a variety of diseases, the power of such examination of skeletons for identification of the etiology of pathology has greatly reduced the need for destructive analysis. High frequency of malformations in amphibians, or of spondyloarthropathy in reptiles should stimulate evaluation for environmental causal factors. Notation of previously unrecognized/undescribed pathology affords unique opportunities. Scientific approach, validated database and phylogeny-independent pathology recognition form the basis for this review of the current knowledge of contemporary and extinct amphibian and reptile osseous pathology. This provides baseline data for forensic herpetologists and others attempting to identify and interpret osseous lesions, disease and trauma in a forensic context. (c) Koninklijke Brill NV, Leiden, 2009
This is an overview of the use of reptiles for medicinal and magic religious purposes in Brazil and discusses their implications for conservation. All available references or reports on the reptiles species being used for medicinal or magic/religious purposes were examined. A total of 44 species of reptiles (35 genera and 17 families) are used. These 42 species are used for medicinal purposes, two for magical religious purposes and 11 for both. The largest numbers of species used were snakes (15 species), turtles and tortoises (14), lizards (10), and crocodilians (5). Therapeutic products from 42 reptile species are used to treat 100 different illnesses and at least 13 reptile species were recorded as having magic religious uses. They are commonly sold in Brazilian cities in outdoor markets and stores that sell religious articles. Of the reptiles recorded, 52.3% are endangered species, demonstrating the importance of understanding such uses in the context of reptile conservation as well as of the cultural, social, and traditional role of these reptiles for establishing management plans directed towards sustainable use.
