Spelling suggestions: "subject:"rule der -- oregon"" "subject:"rule der -- pregon""
1 |
Factors affecting habitat use by black-tailed deer and Roosevelt elk in the Silver Burn, Southwestern OregonMichalski, Bret L. 14 July 1994 (has links)
A wildfire burned over 40,000 ha of conifer and mixed conifer-hardwood forest in
the Silver Creek drainage of southwestern Oregon in the fall of 1987 allowing me to
assess big game use of a large natural burn. I used fecal pellet group counts to estimate
habitat use and effects of forest management activities on Roosevelt elk (Cervus elaphus
roosevelti) and black-tailed deer (Odocoileus hemionus columbianus) within the Silver
Fire Recovery Project Area (SFRPA) of the Siskiyou National Forest. Pellet decay rate
and differences in observers' abilities to detect deer and elk pellet groups (interobserver
variability) were estimated to test validity of pellet group counts. Pellet group
persistence was estimated during a 10-month period. There were no differences in pellet
group persistence between elk and deer (P < 0.05). Observers differed in ability to detect
elk (F = 2.7; df = 4, 530; P = 0.03) and deer (F = 10.7; df = 4, 883; P < 0.0001) pellet
groups. Interobserver variability related to elk pellet groups was low and was attributed
to differences in numbers of transects searched by each observer. Two observers
detected greater mean numbers of deer pellet groups than did other observers. I counted
775 elk pellet groups and 3,888 deer pellet groups on four study areas within the SFRPA.
I analyzed habitat use for two periods: June to mid-October (summer-fall), and mid-
October through May (fall-spring). I used stepwise logistic regression to create models
predicting categories of habitat use during each period. Management variables were
added to the habitat models to estimate effect of management on predicted categories of
habitat use. Total overstory canopy cover was negatively related to deer use during both
use periods. Distance to road was the only significant management variable affecting
deer habitat use during the fall-spring period (P = 0.03). Slash cover had a negative
effect on probability of habitat use by deer during the summer-fall period (P = 0.02). Elk
use was negatively affected by steep slopes and hardwood canopies during both periods,
while grass seeding positively affected elk use during both summer-fall (P = 0.05) and
fall-spring (P = 0.03) use periods. Clearcutting had a negative effect on probability of
elk use during the fall-spring period (P = 0.04). / Graduation date: 1995
|
Page generated in 0.0437 seconds