Potamodromous coastal
cutthroat trout (Oncorhynchus clarki clarki) migrate
only in freshwater. Little is known about the distribution of
potamodromous coastal cutthroat trout within watersheds, how
their distribution changes seasonally, and how ontogenetic development
influences their distribution through time. This information
is especially important to the management of coastal cutthroat
trout because their abundance and distribution have declined
across the historic range of the subspecies. Aquatic habitat
degradation has been identified as a potential cause for these
decreases. Many populations of potamodromous coastal cutthroat
trout are isolated above natural barriers to upstream migration,
in small first-, second-, and third-order streams that are negatively
affected by upslope disturbances, including timber harvest and
road 
building.
Persistence of these isolated populations is directly related
to their capacity to move with seasonal changes in habitat availability
or to demands associated with ontological development.
The purpose of this study is to (1) examine distribution
of coastal cutthroat trout in a third-order watershed in the
Umpqua River basin that is isolated above a barrier to anadromous
salmonids and (2) monitor movement and habitat-use of marked
fish over a period of 14 months. Variation in movement patterns
and 
habitat
relationships will be evaluated for all life stages of coastal
cutthroat trout (juveniles, subadults, and adults). This will
be accomplished by examining the entire watershed at various
spatial scales (e.g., watershed, stream, segment, reach, and
channel unit), and identifying environmental variables that
are related to changes in habitat availability and fish movement.
For additional information about this completed research study
see the 2002
CFER Annual Report. (2.2 MB)
