PERSONAL
COMMUNICATION
­
PHONE
CALL
TO:
Jim
Williams,
U.
S.
Geological
Survey
FROM:
Sue
Humphries,
Stratus
Consulting
Inc.
DATE:
4/
19/
2006
RE:
Freshwater
mussels
Asked
about
current
and
historical
ranges
and
populations
of
freshwater
mussels
as
well
as
factors
currently
impacting
mussels.
He
said
that
85­
90%
of
native
species
are
currently
imperiled,
10­
15%
are
maintaining
or
expanding
their
ranges,
and
that
mussels
occur
in
many
aquatic
environments.
Also,
he
said
that
current
threats
to
mussels
include
pollution
from
point
and
nonpoint
sources;
changes
in
stream
hydrology
caused
by
dams
and
channelization;
siltation
from
runoff
and
dredging;
and
competition
with
invasive
species
such
as
zebra
mussels.
