The Northern Leopard Frog has undergone population declines and local extirpations throughout the northwest, including Alberta, Idaho and Washington (Adama et al., 2003; Seburn and Seburn, 2000). It was never widespread in British Columbia, with only about 12 historic locations in the Okanagan, Kootenay, and Columbia River Valleys (BC Conservation Data Centre 2005). Since the 1970s, numbers have declined noticeably and, by the mid-1990s, only a single population was known within the Creston Valley Wildlife Management Area south of Kootenay Lake (Waye, 1999). Declines have mostly been a result of the conversion of wetlands to agricultural land and other uses. Habitat may have been changed by an influx of invasive plant species, and competition and predation by non-native predatory species such as exotic fish and Bullfrogs (Seburn and Seburn 1998) have no doubt played a role. 'Recent studies have suggested that the surviving Creston population is losing breeding adults at a precipitous rate, which may be due to chytrid fungal infections (Batrachochytrium dendrobatidis)' (BC Conservation Data Centre, 2005). Dead adults have been found with sloughing skin and bleeding extremities, and tests have indicated the presence of chytrid fungus (Adama et al., 2004). Attempts have been made to 'head-start' developing frogs by collecting egg masses and raising tadpoles in captivity, then releasing them into historically known locations (Adama et al., 2004).
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