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Disease, pollution, invasive species, overcollecting, global changes, and other causes have been documented or proposed to be responsible for particular or widespread amphibian population declines. Yet, finding solutions for any of these causes will not matter for most species in the long term if the basic components of their natural habitats are degraded or eliminated by human use of natural resources. Partners in Amphibian and Reptile Conservation (PARC) is an initiative designed to find solutions to the loss of habitat and other problems faced by herpetofauna. Groups or individuals with an agenda involving beleaguered amphibians (frogs, salamanders, and caecilians) are encouraged to become involved with PARC. PARC differs from many other conservation groups. PARC recognizes that reptiles are more globally threatened than are amphibians, and, hence, these two major classes of vertebrates are coupled in conservation efforts. PARC has been organized to involve not only the person or group with a concern for amphibians and their habitats, but also any person or group whose actions and attitudes are perceived by some as detrimental to the well-being of amphibians.

This last chapter deals with differences and similarities between British and European and North American Pleistocene herpetofaunas. Compared with North America, Britain and Europe had a depauperate Pleistocene herpetofauna, which has carried over into modern times. For instance, the large, “warm” country of Spain, which by European standards has a rich modern herpetofauna, has only 13 species of snakes and four species of nonmarine turtles (Engelmann et al., 1986). On the other hand, Michigan, a northern border state with cold winters, has 17 species of snakes and 11 species of turtles (Holman et al., 1989; Harding and Holman, 1990). Indiana, just south of Michigan, has 31 species of snakes and 15 species of turtles (Minton, 1972; Brown, 1996; Conant and Collins, 1991). The southern coastal state of Florida has 45 species of snakes and 20 species of nonmarine turtles (Conant and Collins, 1991). This is almost twice as many snakes and more than three times as many nonmarine turtles as occur in Britain and Europe. In the Pleistocene, British or European herpetofaunas are considered to be rich when they contain 10 species. In North America, Pleistocene herptofaunas with more than 20 species are common, and sites with more than 40 herpetological species are known (Holman, 1995c). The reasons for these differences are as follows. Both North America and Europe became herpetologically enriched in the Miocene. But the climatic deterioration at the end of the Miocene caused a depletion of the herpetofauna in Europe. Because Europe was mainly isolated from Africa by the Mediterranean Sea and from warm areas to the east by mountain ranges and seas, its depauperate herpetofauna persisted into modern times. Ireland and Britain have even more depauperate modern herpetofaunas than the continent because these islands were cut off from the mainland before they could be reinvaded by all of the species displaced by the last glaciation (Fig. 45). In North America, however, with a vast, accessible southern land mass, and equable Pleistocene climates south of the periglacial regions (Lundelius et al., 1983), the richness of the Miocene herpetofauna persisted into Pleistocene and modern times.

The herpetofauna of Mesoamerica is one of the richest and complex vertebrate faunas, involving more than 210 genera, comprising approximately 693 species of reptiles and 598 species of amphibians. This chapter examines the biodiversity and biogeographical aspects of reptiles and amphibians in the dry-forest environments of Mesoamerica. It discusses their resource and microhabitat use, feeding ecology, reproduction, and adaptations to the changing seasonal climate. Finally, it discusses some of the recommendations for the conservation of herpetofauna of Mesoamerican dry forests.

This chapter examines the fossil herpetofauna of Porcupine Cave. It documents the presence and taxonomic diversity of amphibians (salamanders and anurans) and reptiles (lizards and snakes) that are recovered from the cave, and explores the paleoclimatic information which can be derived from the study of these remains when they occur in controlled stratigraphic contexts. The combined sample of amphibians and reptiles from all localities within the cave includes only 141 specimens representing a minimum of seven taxa. Snakes are represented by a greater number of fossil specimens (117) than any other herpetofaunal group from Porcupine Cave.

Baja California's ecological transformations and diverse climactic regimes have contributed to its biotic diversity. This book examines the physiographic nature of Baja California to provide better insights into the distribution and geographic variation of its herpetofauna. It discusses the biological exploration and history of herpetological research in Baja California and the Gulf of California (the Sea of Cortés). It also provides information about faunal relationships, historical biogeography, and ecological biogeography of amphibians and reptiles in these regions.

In several recent analyses a unified framework is developed for organizing information to decide whether to allow intentional trade of a potentially invasive species. Recent estimates of the expected net benefits from upfront invasion risk assessment for different groups—plants for planting and herpetofauna—fall in a range from $54K-$141K per species assessed, suggesting substantial returns to a proactive approach. Two essential components of this risk assessment framework include (1) a statistical-ecological model of species invasion threat, and (2) a mechanism for mapping potential benefits and costs from trade into a threat level threshold beyond which non-native species are deemed too risky for importation. Data and future research needs for improving ecological-economic risk assessment of potentially invasive biological imports include: (1) better estimates of invasion welfare losses by taxon, (2) broader estimates of import benefits that assess benefits generated throughout the import value chain, (3) consistent collection, maintenance and access to detailed trade data.

This chapter explores how the ability of herpetofauna to persist and/or thrive in urban ecosystems is constrained by some of the very traits that characterise them, including relatively limited dispersal capacity, high trophic level, and ectothermy. In particular, it considers the ecology of amphibians and reptiles found in cities; their roles in urban ecosystem food webs, energy flow, and biogeochemical cycles; whether they help stabilise ecosystem function amidst the disturbance that persists in urban environs; and whether these taxa can serve as indicators of environmental stress and successful urban ecosystem re-engineering for sustainability. It also looks at the characteristics of urbanophiles, urbanophobes, and the urbanoblivious.

This chapter examines the effects of Tamarix invasion and Tamarix control on the use of riparian habitats by wildlife species such as birds, mammals, and herpetofauna. Birds, mammals, and herpetofauna are secondary consumers within a riparian food web, capable of providing a tool to evaluate how the establishment and proliferation of exotic species such as Tamarix can induce ecosystem-level changes. The chapter begins by comparing Tamarix with native or mixed habitats (defined as stands composed of nonnative Tamarix and native tree species, mainly cottonwood and willow) and proceeds by considering how the establishment and proliferation of Tamarix can lead to ecosystem-level changes. It also highlights data gaps with respect to the impact of Tamarix on most species of wildlife and suggests directions for future research.