Upper Midwest Environmental Sciences Center
Paddlefish Study Project
Paddlefish (Polyodon spathula) were
a common component of fish communities in the large rivers of the Mississippi
River drainage before 1900. Overharvest and human alteration of rivers
have resulted in significant declines in paddlefish populations. Construction
of dams on rivers has especially affected paddlefish by altering traditional
river habitats and disrupting spawning migrations and other movements.
Paddlefish have been lost from four states and Canada, and 11 of 22 states
within the remaining species range now list the paddlefish as endangered,
threatened, or a species of special concern. Restoration of paddlefish
populations is a shared goal of many state and federal agencies
Center scientists, in collaboration with the U.S. Fish and Wildlife Service,
tagged 71 paddlefish with radio-transmitters in the Upper Mississippi
River and two tributary rivers and tracked their movements from fall 1994
to fall 1997. Specific study objectives include identifying the important
features and availability of critical habitats and assessing the role
of dams in impeding migrations and fragmenting populations.
Results of this work will provide state and federal biologists with information
to evaluate the effects of river modifications on paddlefish populations
and determine options for managing paddlefish populations and their habitats.