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The global decline of amphibians has received a great deal of attention (Wake, 1991; Wake and Morwitz, 1991; K. Phillips, 1994) and serves as an indicator of a larger problem involving the decline of overall biodiversity associated with uncontrolled human population growth. In North America, amphibians have declined due to environmental alteration associated with timber harvesting, agriculture, wetland drainage, urbanization, stream pollution and siltation, and the introduction of exotic predators (Orser and Shure, 1972; Bury, 1983; Gore, 1983; Hayes and Jennings, 1986; Pierce and Harvey, 1987; Ash, 1988; Welsh and Lind, 1988; Blaustein and Wake, 1990, 1995; Pechmann et al., 1991; Petranka et al., 1993, 1994; Vial and Saylor, 1993; Fisher and Shaffer, 1996; Gamradt and Kats, 1996). In the midwestern United States, which includes Ohio, severe declines of certain amphibian species have occurred and are continuing to occur (Lannoo, 1998b). Disturbingly, broad-ranging, common species such as Fowler’s toads (Bufo fowleri) and Blanchard’s cricket frogs (Acris crepitans blanchardi) have recently disappeared from certain portions of their ranges in Ohio and other states (J. Davis, J. Harding, and S. Moody, personal communication). This alarming trend in population declines of an array of amphibian species in and around Ohio indicates that additional conservation measures are needed within the state, not only for those species considered endangered, but for all species. Adding to this concern is the destruction of 90% of Ohio’s wetlands within historic times, which represents a decline in habitat critical for many amphibian species (Sibbing, 1995). Ohio is home to 14 species and subspecies of frogs and toads, and 26 species of salamanders. Nine families are represented among these two groups, demonstrating the high level of amphibian diversity within the state. Of the 40 species, five are listed as endangered and one of special interest by the Ohio Department of Natural Resources, Division of Wildlife. Endangered species include eastern hellbenders (Cryptobranchus a. alleganiensis), blue-spotted salamanders (Ambystoma laterale), green salamanders (Aneides aeneus), cave salamanders (Eurycea lucifuga), and eastern spadefoot toads (Scaphiopus h. holbrookii). Four-toed salamanders (Hemidactylium scutatum) are listed as special interest. Thus, about 19% of Ohio’s salamanders are listed as endangered or special interest, as are about 7% of the frogs and toads. Overall, 15% of the state’s amphibians are contained within these protected categories. Due to these alarming trends of amphibian population declines , decisive conservation measures must be taken. It is the purpose of this paper to present practical methods, thought processes, and other considerations to stimulate establishment of a reserve network for all Ohio amphibian species based on distribution. Specifically, areas critical for amphibian conservation are evaluated by (1) defining biological “hotspots;” (2) defining a minimum reserve network (minimum number of reserves ) to conserve all Ohio amphibian species; and (3) evaluating the use of existing protected land in forming an amphibian reserve network. We emphasize that the information we present is only a first stage or coarse analysis in defining a reserve network and that further refinement is needed to define precise locations of reserves. Further, the presence of viable amphibian populations, habitat quality, land availability, current land use practices, land cost, and other factors important in reserve formation and function at the sites indicated are unknown. Such information can be obtained through field surveys and consultation with individuals familiar with the chosen areas. Materials and Methods The Algorithms SOURCES OF DATA Ohio amphibian distribution data were taken from Pfingsten and Downs (1989), Pfingsten (1998), and Davis and Menze (2000). Tremblay’s salamanders (A. tremblayi) and silvery salamanders (A. platineum) reported from Ohio (Pfingsten and Downs, 1989) are considered hybrids, and thus are not included in this analysis (for summary of hybrid discussion see Klemens, 1993; for an alternative viewpoint see Phillips and Mui, this volume, Part Two). Locality records were reported by township, with these areas used as the distribution units. For subsequent analyses an absence/presence matrix was formed comparing all species to all townships. This resulted in 8,066 records in the 1,343 Ohio townships. Of these townships, 86 had no amphibian records. Townships average 30 mi2 within the 40,740 mi2 political area of Ohio, and most townships are 247 TH I RTY-F IVE Critical Areas HUGH R. QUINN AND COLLEEN SCOTT roughly square. Size range is approximately 5–65 mi2 , however, in the south-central portion of the state, their shape and size are more irregular. CHOOSING ALGORITHMS There are 19 algorithms that have been utilized in selecting nature reserve networks, all of...

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