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Endangered Species Management Chapter 16. Protected Fishes. 743 native species in US & Canada 418 species (56%) receive some degree of endangered species protection 235 species (32%) are fully protected in all or part of their range by some governmental agency. The Problems.
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Protected Fishes • 743 native species in US & Canada • 418 species (56%) receive some degree of endangered species protection • 235 species (32%) are fully protected in all or part of their range by some governmental agency
The Problems • Habitat modification (98%) • Other natural, human factors (intro of exotics) (37%) • Restricted range (16%) • Overexploitation (3%) • Disease (2%)
The Result Bluepike • 27 species, 13 subspecies have gone extinct in North America in past century
Today’s Endangered/Threatened Species Bluepike • 80% in SW or SE United States • 60% are stream fishes (90% warmwater)
Problem Areas • Death Valley - water withdrawals
Problem Areas • Colorado River basin - habitat loss/modification, introduction of nonnative species
Problem Areas • Western trouts - introgression with nonnative trout
Management Today • Maintain/enhance historic populations • Protect, expand, restore habitat • Move specimens to refugia
Management Today • Rear/stock in additional habitats • Minimize conflict with nonnative species • Control exploitation
Today’s Trend • Movement away from single-species approach to ecosystem approach • Inherent need to recognize importance of nongame fishes