Trends in Commercial Roe Harvest in the Missouri and Mississippi Rivers from 1945-2010

Overexploitation creates an imbalance in natural ecosystem function and jeopardizes the livelihood of commercial fishers.  Despite the problems created by overexploitation, trends of commercial harvest on large inland river roe-bearing populations have received minimal attention.  As such, we evaluated trends in commercial fishing data from 1945-2010 for two roe-bearing species (paddlefish Polyodon spathula and shovelnose sturgeon Scaphirhynchus platorynchus) from the Mississippi River and Missouri River adjacent to Missouri.  Commercial harvest has varied from ~300 to 29,000 kg over the course of the 55-year duration.  Peak catches of both species occurred in 1980, 1990, and 2001. These high catches corresponded to initiation of worldwide caviar markets, regulations on the Missouri and Mississippi rivers, and the Caspian Sea fishery collapse.  Furthermore, our results suggest that harvest of paddlefish and sturgeon have increased substantially since 1945.  Despite the increased harvest of paddlefish and sturgeon and the possibility of overharvest, commercial fishing regulations have not been evaluated for effectiveness.  Evaluation of these regulations through collaborative efforts with commercial fisherman need to be examined to maintain a sustainable fishery.  We suggest future efforts should be directed at direct observation of commercial catch to measure population demographics to aid in the development of population viability models.