environment, can live for more than 100 years.
While many mussel populations may look healthy
and diverse, some are actually aging, non-reproducing
populations in severe decline. As sedentary organisms,
they can't simply pack up and move like birds or
mammals if their habitat undergoes major changes.
This immobility and the changes that have occurred
in the state's waterways may explain why only 12
of the 30 species of freshwater mussels native to
Nebraska have sustainable populations, leaving the
other species endangered, threatened or extirpated. Of
the 297 mussels species found in the United States,
70 percent are listed as endangered by federal or state
agencies, threatened or of special concern, making
them one of the most imperiled animal groups in the
country.
Threats
Real threats for freshwater mussels include habitat
alteration caused by impoundments, river and stream
channelization, siltation, chemical runoff, pollution,
drought and dewatering, overharvest, physical damage
and the invasion of exotic species such as zebra
mussels.
Historically, the first threats came in the late 1800s
during the "pearl rush," where millions of mussels
were harvested in search of freshwater pearls. The
42 NEBRASKAland • APRIL 2017
Joe Cassidy (left) and Bryan Sweet use a telemetry device on tagged mussels before releasing them into Cache Creek in Holt
County. Josh Cloeter (right) releases tagged mussels into the creek bed.
This is an old mussel shell used to make clothing buttons from
the mother-of-pearl (also known as nacre). Mother-of-pearl is the
iridescent inner layer of the mussel shell that would be the front
of the button.
