88
Zebra mussel, Dreissena polymorpha
Description: The Zebra mussel is a
small, thin-shelled mussel that rarely
gets over 35-40mm. The shell is
smooth and often has a pattern of
light and dark bars suggestive of a
zebra's stripes. One site of the shell is
flat and the other side is curved giving
it a D-shaped appearance. Zebra
mussels extrude a tough fiber called a
byssal thread that it used to attach
itself to any hard surface.
Similar species: There are no
freshwater mussels that look like a
Zebra mussel.
Conservation status: None. This is
an exotic invasive species in
Nebraska.
Hosts: None. This species can
reproduce without a host.
Habitat: The Zebra mussel doesn't
seem to be too particular as it can live
in freshwater or brackish water. They
attach themselves to hard surfaces so
areas with rocks, pilings, boat docks
and boats can be heavily infested.
They do better in flowing water
because these will provide a better
food supply.
Distribution: They are now found
though much of the Mississippi River
basin east of Nebraska, the Great
Lakes watershed, the St. Lawrence
River and Hudson River.
Collection notes: The first live Zebra
mussels found in Nebraska were in
the Offutt Base Lake in Bellevue in
2006. A few years later, they were
found in Zorinsky Reservoir in
Douglas County. In 2015, they were
found at several locations in Lewis
and Clark Lake.
Comments: The Zebra mussel does
not have parasitic larvae and can
reproduce without the need for a host
fish. There were attempts to eradicate
the populations in Offutt Base Lake
and Zorinsky Reservoir. As of this
writing, the eradication effort in
Offutt Base Lake was a failure but the
Zorinsky Reservoir attempt
apparently was successful. In 2015,
live populations were found in Lewis
and Clark Lake above Gavins Point
Dam. Since then, they have been
found in the Missouri River below
Gavins Point Dam. It is to be
expected that these populations will
continue to expand.
