Threatened fishes of the world: Salvelinus confluentus (Salmoninae)

Abstract

Common name: Bull Trout; Bull Charr. Conservation status: Vulnerable IUCN Red List; Threatened, U.S. Fish and Wildlife Service (1999). Identification: Adults to 14 kg, olive green to brown body fading to white on belly with yellow spots dorsally grading to red to orange laterally. White leading edges on rayed fins, solid colored dorsal fin (Cavender 1978; Markle 1992) (Illustration: copyright Joseph R. Tomelleri). Distribution: Northern California to Alaska, eastward extent Nevada, Montana, and Idaho (Cavender 1978; Haas and McPhail 1991). Canadian distribution includes British Columbia, Central Northwest Territories, and western Alberta (Reist et al. 2002). Currently extirpated from California with local extirpations scattered throughout the remainder of the species’ range (USFWS 1999). Habitat and ecology: Highly variable movement behavior spanning a continuum between resident and migratory individuals. Spawning and rearing confined to colder ( 12 years (Zymonas 2006). Autumn to early winter spawning in headwater streams (Fraley and Shepard 1989; McPhail and Baxter 1996). Fecundity ranges from 2,000 to 12,000 eggs, with emergence of fry in late winter to early spring (Fraley and Shepard 1989). Threats: Threats include angling (Schmetterling and Long 1999), habitat loss and fragmentation (Dunham and Rieman 1999), nonnative trout, hybridization (Baxter et al. 1997), disease (Post et al. 2003; USFWS 1999), and pollution (Post et al. 2003; USFWS 1999). Bull trout are particularly vulnerable to threats due to long embryo incubation, relatively old age at maturity and reliance on pristine habitat (Pratt 1992; Rieman and McIntyre 1993). Conservation actions and recommendations: Address known threats, public outreach, research evolutionary history, ecology, and conservaEnviron Biol Fish (2010) 89:161–162 DOI 10.1007/s10641-010-9708-8