better understanding of the potentially complex life history requirements
of westslope cutthroat trout in headwater basins is critical to managing
for the persistence of the subspecies. This study investigated cutthroat
trout habitat use and movement over the course of a year and at the headwater
basin-scale; and used radio telemetry, a method that permits the detection
of movement over long distances. This study answered two important questions:
How do the habitat associations of westslope cutthroat trout in headwater
basins change seasonally?
How does the spatial distribution of habitat patches influence the seasonal
movements of westslope cutthroat trout in headwater basins?
order to accomplish these objectives, adult westslope cutthroat trout
(>200 mm) habitat associations were assessed at several spatial scales
over a 17-month period. A stream habitat inventory of the entire study
area was completed in July 2001. To assess the seasonal dynamics of the
study area, continuous year-round stream temperature and weekly discharge
data were recorded. Habitat use information was gathered by tracking 70
cutthroat trout tagged with surgically implanted radio transmitters, from
August 2000 to January 2001. Each fish was located on a weekly basis,
and stream habitat variables and movement distance were recorded each time
a fish was located. From these data, habitat associations based on an
electivity index were calculated for several spatial scales, including
the channel unit, reach (sensu Montgomery and Buffington 1997), and valley
segment (sensu Frissell et al.
1986) and compared for differences among
seasons. To assess the influence of habitat on movement, the movement
of fish tagged in stream areas of high spatial habitat heterogeneity (e.g.,
abundant instream large wood, high pool frequency and residual pool depth,
and unconstrained reach) was compared to the movement of fish tagged in
areas with low spatial habitat heterogeneity.
Annual Reports and Publications:
Starcevich, S.J. 2005.
Seasonal movement patterns and habitat use of westslope
cutthroat trout in two headwater tributary streams of the John Day River. Master's
thesis. Oregon State University, Corvallis.
Gunckel, S.L. 2002.
Stocking history of westslope cutthroat trout and rainbow trout
in the upper John Day basin, Oregon. Oregon Department of Fish and
Wildlife, Annual Progress Report, Corvallis.
A. and S.J. Starcevich. 2001.
Trout Studies, 2001 Annual Progress Report.
Oregon Department of Fish and Wildlife, Sport Fish Restoration Project F-136-R-14,
Annual Progress Report, Portland.
A. and S. Starcevich. 2000.
Trout Studies, 2000 Annual Progress Report.
Oregon Department of Fish and Wildlife, Sport Fish
Restoration Project F-136-R-13, Annual
Progress Report, Portland.
Trout Studies, 1999 Annual Progress Report.
Oregon Department of Fish and Wildlife, Sport Fish Restoration
Project F-136-R-12, Annual Progress Report,