Fish Passage Study
ODWC is cooperating with the US Forest Service, the US Fish and Wildlife
Service, and Weyerhaeuser, John Hancock and Georgia Pacific companies in
researching bridge crossings in Southeast Oklahoma. The Three Rivers and Honobia
Creek WMA’s and Ouachita National Forest contain an extensive road network to
support the timber industry in the region. This road network includes thousands
of bridges and many of them impact natural stream function, degrade stream
habitat and present movement barriers to fish. While all of these impacts are of
serious concern, the movement issue is of chief importance because fish may not
be able to reach preferred habitat or successfully disperse and pass on
important genetic information. Species at risk in the region include sportfish
such as smallmouth bass and the threatened leopard darter.
Several bridge crossings in the region will either be removed or replaced in the
near future because of severe wear from logging trucks that has deteriorated
their structural condition. This study will look at the shape and function of
the stream both before and after bridge removal to assess the impacts of bridges
and their removal or replacement on stream morphology which is directly related
to fish movement. This study will be beneficial in helping to develop better
bridge designs that will have a lesser impact on stream systems and the fish
communities that inhabit them. It may also encourage the removal of bridges that
are not of high importance to timber companies.