“What's for Dinner? A Diet Survey of Columbia River White Sturgeon: They Are What They Eat, Which Is a Little Bit of Everything!”

As any sturgeon fisher can attest, white sturgeon can be notoriously picky eaters, contrary to their reputation as indiscriminant bottom feeders.  Surprisingly little is known about white sturgeon food habitats, particularly in Columbia River reservoirs.  Hydro-electro development has substantially altered the historic aquatic community and associated prey base for white sturgeon.  In February and March of 2009; gastro-intestinal tracts (GIT) were collected from commercially harvested white sturgeon caught by tribal fishers in the Zone 6 commercial fishery.  A total of 196 samples were collected from Bonneville (n=66), The Dalles (n=70), and John Day (n=59) reservoirs, respectively.  Samples were sorted in to  specific categories including fish, crayfish, clams, snails, plant material, and miscellaneous.  Sorted items were counted and weighed to the nearest tenth of a gram.  When possible, materials were keyed to the species level and enumerated as whole animals.  Analyses revealed a diverse diet with marked differences between reservoirs.  Differences in food items among reservoirs may be related to differences in habitat condition and sturgeon population densities in each reservoir.