SAVING THE HIGGINS EYE PEARLYMUSSEL (LAMPSILIS HIGGINSII) FROM EXTINCTION: 2003 
STATUS REPORT ON THE ACCOMPLISHMENTS OF THE MUSSEL COORDINATION TEAM

Gary J. Wege
U.S. Fish & Wildlife Service, 4101 East 80th Street, Bloomington, MN, 55425-1665
Zebra mussels (Dreissena polymorpha) are an exotic species and a significant 
threat to native freshwater mussels of the Upper Mississippi River (UMR).  At 
high densities, they compete for food, prevent opening/closing of shells, 
degrade habitat conditions, and prevent successful reproduction and recruitment.  

Zebra mussels attach to nearly all underwater objects including large boats 
using the federal navigation system of locks and dams on the UMR.  In April, 
2000, the U.S. Fish & Wildlife Service (Service) determined that continued 
operation and maintenance of the federal 9-Foot Channel Project would jeopardize 
the continued existence of the federally-endangered Higgins eye pearlymussel 
(Lampsilis higginsii).  To avoid jeopardy, the Service recommended the U.S. Army 
Corps of Engineers establish populations of Higgins eye in areas with no/few 
zebra mussels, and implement a zebra mussel control program.  Since April, 2000, 
a variety of conservation measures have been implemented including genetics 
studies, propagation of mussels at the Genoa National Fish Hatchery, propagation 
in cages in the UMR and tributaries, stocking juveniles, relocating adults, 
stocking glochidia-inoculated fish, cleaning and stockpiling adults, and 
survey/monitoring activities.  

Keywords:  Higgins eye pearlymussel, Mississippi River, glochidia, Lampsilis 
higginsii, propagation