Status and Habitat use of Pallid Sturgeon 'Scaphirhynchus albus', Sicklefin Chub, 'Macrhybopsis meeki', and Sturgeon Chub, 'Macrhybopsis gelida', in the Middle and Lower Mississippi Rivers

摘要

A decline in the range of sicklefin chub, Macrhybopsis meeki, and sturgeon chub, Macrhybopsis gelida, prompted the U.S. Fish and Wildlife service to consider listing these species as threatened under the endangered species act. Pallid sturgeon, Scaphirhynchus albus, was listed by the U.S. Fish and Wildlife service as an endangered species September 6, 1990. Little information is known about these species in the Middle and Lower portions of the Mississippi River. The U.S. Fish and Wildlife Service funded a project completed by the Open River Field Station (ORFS) in 1998 that provided some information on all of these species. However, additional life history information was lacking. From 2000-2001, the ORFS studied these three species and emphasized spawning and rearing habitats during four sampling time periods at five sampling stations. Two-hundred-thirty-one benthic trawl hauls captured 636 sturgeon chub, 190 sicklefin chub, and three larval pallid sturgeon.