STATUS OF FRESHWATER MUSSELS (BIVALVIA: UNIONIDAE) OF THE BIG THICKET REGION OF EASTERN TEXAS

摘要

Freshwater mussels (Unionidae) are one of the most rapidly declining faunal groups in North America. Among the 52 recognized taxa in Texas, at least 42 have been reported in or near the Big Thicket Region of eastern Texas (Sulphur River to Buffalo Bayou drainages). Current findings indicate in some areas of eastern Texas several unionid species have maintained significant populations and continue to support commercial and sport fisheries. However, other taxa have become extremely rare and several have not been seen alive in the past 10 to 15 years. Nine species have been considered to be threatened, endangered, or of special concern by the American Fisheries Society. Population declines regionally typically reflect both aquatic and terrestrial habitat modification and degradation, historical and current pollution, and wide-ranging human development. Currently known status of mussel species and river systems is summarized herein.