Several aspects of the physiology and diseases of the North American elk (Cervus canadensis) were investigated, toward the goal of uncovering influences responsible for declining productivity among some elk herds in Oregon. A newly developed drug, Etorphine, together with its antagonistic companion, Dip renorphine, was used to immobilize elk. Substantial differences were found in the amounts required and animal responses dependent upon age, physical condition and life history. Whole blood samples were obtained from 60 living elk for hematological studies. The parameters examined included hemoglobin levels, packed cell volume, erythrocyte and leukocyte counts, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular volume, and the percentage distribution of neutrophils, band cells, lymphocytes, monocytes, eosinophils, and basophils. Respiration rate, heart rate, and body temperature were measured for nine drugged elk. Sickling of erythrocytes was found in the blood of two female elk. Serum was separated from the blood of 72 living elk and 22 recently shot elk of mixed ages and sexes. Serum proteins were differentiated by electrophoretic analysis. Values obtained for total protein, albumin, total globulin, albumin/globulin ratio, and for the alpha1, alpha2, beta and gamma globulins, were grouped and summarized to facilitate comparisons based on age and sex, as well as between living and dead, and captive and free-living elk. Total serum protein concentrations were markedly higher in the older age groups of both captive and freeliving elk. An apparent tendency to higher albumin levels was found among males of this species. Values for serum concentrations of sodium, potassium, calcium, inorganic phosphorus, blood urea nitrogen, Chlorides, Cholesterol, glucose, direct bilirubin, total bilirubin, creatinine, and uric acid, as well as activity levels of alkaline phosphatase, lactic dehydrogenase, and serum glutamic oxalacetic transaminase were obtained. Sodium/ potassium and calCium/phosphorus ratios were calculated. Urine speciments were obtained from seven elk and analyzed for the presence of glucose. Young elk, both captive and free-living, had higher serum values for sodium, calcium, inorganic phosphorus, glucose and alkaline phosphatase than did the older age group. Mature elk, both captive and free-living, had higher serum values for calcium/phosphorus ratio, blood urea nitrogen, creatinine, uric acid and serum glutamic oxalacetic transaminase than did those under two years of age. Differences in serum Chemistry were also found between captive and free-living elk. Serological tests on sera from 67 elk tested were negative for brucellosis and bluetongue virus. Tests for leptospirosis on sera from 29 elk by the macroscopic agglutination method were all negative. Of 38 free-living elk tested for leptospirosis by the microscopic agglutination test, 16 showed positive reactions to one or more serotypes at a significant titer of 1:100 or greater. Another eight showed positive reactions at the 1:50 level. This is believed to the first report of serological reactivity to leptospirosis reported for elk. Internal organs from 39 elk were examined for the presence of adult helminths, and fecal pellets from 82 elk were examined for the presence of parasite eggs. Lethal numbers of Dictyocaulus viviparus were recovered from the respiratory organs of two yearling male elk. Two nematodes of the Trichostrongylus axei and Ostertagia circumcincta, were found that have not been previously reported from Roosevelt elk. Fascioloides magna and Oesophagostomum venulosum were also found. The common winter tick, Dermacentor albipictus and Ixodes pacificus were collected from Roosevelt elk. This latter species has not been previously reported in elk. Increased gannna globulin values and concomitant decreases in albumin were observed in tick-infested elk.

Research was conducted near the Starkey Experimental Forest and Range in northeastern Oregon. Effects of defoliating bluebunch wheatgrass (Agropyron spicatum (Pursh) Scribn. and Smith) to increase the quality of regrowth available on elk (Cervus elaphus nelsoni) winter range were studied from 1988 through 1990. Clipping treatments were implemented to condition the forage regrowth. Treatments were no defoliation, spring defoliation (7.6 cm stubble height) in June, and fall defoliation (7.6 cm stubble height) in September. Percent calcium, phosphorus, in vitro dry matter digestibility (IVDMD), and available forage (kg/ha DM) of regrowth present on control, spring defoliated, and fall defoliated plots were determined in November and April of both years. Conditioned forage that was again defoliated in the winter was also analyzed for nutrient quality and available forage. Spring conditioning did not affect (p > 0.05) the forage in percent calcium, phosphorus, or available forage, and only slightly increased the IVDMD, when compared to the control in November. In November, the control and spring conditioned forages were deficient in meeting elk requirements for phosphorus, and contained wide calcium to phosphorus ratios. The forages were below 50% IVDMD, and digestible energy levels were below animal requirements in year 1, indicating that spring conditioning did not have an effect on the quality of winter range forage. Defoliation in the vegetative phenology stage allowed the regrowth to complete the growing season similarly as undefoliated plants. Fall conditioning significantly increased the percent phosphorus and IVDMD, while decreasing the available forage compared to the control and spring conditioned forage in November. Fall conditioned forage exceeded elk requirements in both calcium and phosphorus. The calcium to phosphorus ratio was near the optimum absorption range. Digestibility was high, and digestible energy levels were above animal requirements for both years. Fall conditioning however, may create a severe deficit of forage if regrowth is not achieved. In April, there were no differences among treatments in percent calcium, phosphorus, or available forage. Forage from all treatments exceeded elk requirements in calcium and phosphorus, and the calcium to phosphorus ratio would allow optimum absorption of both minerals. Digestibility was high for forage from all treatments. This indicated that the previous years defoliation did not effect forage quality the following spring. Conditioned forage that was again defoliated in the winter was not different in percent calcium or phosphorus when compared to the control in April. Depending on the year and conditioning treatment, there were statistically significant differences in IVDMD and available forage between the control and the winter defoliated samples in April. Conditioned forage that was not defoliated in the winter (April (U)) and winter defoliated samples (April (W)) were comparable in forage quality and available forage in April, though statistical differences were calculated for the spring conditioned samples in year 1, and fall conditioned samples in year 2. / Graduation date: 1992

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

The Roosevelt elk (Cervus elephus roosevelti) is a National Forest management indicator species on the westside of the Cascade mountains, Western Oregon. A Habitat Effectiveness model is used by State and Federal agencies to evaluate elk habitat in the region. Concerns about the model's lack of differentiation between winter and summer ranges in the analyses and assumptions that burning will increase forage quality on winter range prompted this study. I investigated the effect of broadcast burning, plant association, and time since disturbance on the quality of trailing blackberry (Rubus ulna), red huckleberry (Vaccinium parviflorum), willow (Salix spp.), vine maple (Acer circinatum), salal (Gaultheria shallon), and red elderberry (Sambucus racemosa). Crude protein, neutral detergent fiber, acid detergent fiber, acid insoluble ash, lignin, astringency, condensed tannin, and hydrolyzable tannin contents were measured. No significant effects of burning, plant association, or age were observed for crude protein, hydrolyzable tannins, or neutral detergent fiber. Crude protein varied among taxa: trailing blackberry contained 9.65%, and the other taxa ranged from 5.21-7.24%. Neutral detergent fiber was highly variable: trailing blackberry contained 30.90%, and the other taxa ranged from 52.20%-65.06%. Acid detergent fiber content ranged from 44.88%-49.49% for all taxa except trailing blackberry (17.78%). Lignin varied among taxa: trailing blackberry had the lowest content (6.37%) and salal had the highest (30.25%). Lignin content in salal was greater on recently disturbed sites. Astringency ranged from 0.0015 mg protein precipitated per mg plant tissue in vine maple to 0.6737 in trailing blackberry. Salal and willow had intermediate astringencies: elderberry, huckleberry, and vine maple had the lowest. Hydrolyzable tannins were present in all species except red elderberry. Burning and plant association effected astringency and condensed tannin content in trailing blackberry and huckleberry. Samples from burned, very dry and resource-poor sites had higher astringencies than on similar unburned units and non-resource-limiting sites. Condensed tannin contents increased with unit age in salal, huckleberry, and trailing blackberry, possibly accumulating during peak years of re-establishment after disturbance. Vine maple and red huckleberry were the only taxa with positive digestible protein levels. Digestible protein content may be higher in winter forage on less severe sites. Elk forage enhancement in winter range should be evaluated on a site-specific basis. Burning did not promote a detectable increase in quality for these forage taxa, and it decreased the quality of species sensitive to site conditions. / Graduation date: 1991

This research was conducted on three study areas on elk winter ranges in Northeast Oregon. One was on the Starkey Experimental Forest and Range and the others were in the same vicinity. Plant appendages, spring and fall defoliation and fall growth of bluebunch wheatgrass were evaluated in terms of quality of nutrient content during September through April of 1986-87 and 1987-88. Four treatments were applied. Plants were clipped to a 2.5 cm and 7.6 cm stubble height in the spring before the boot stage of phenological development; plants were clipped to a 7.6 cm stubble height in the fall after plant maturity in September; plants were not clipped during the year. Percent crude protein, dry matter digestibility (DMD), acid detergent fiber (ADF), and lignin were evaluated monthly. Samples from the four treatments were also analyzed from October to April to determine monthly changes in nutrient contents. Production of growth from all treatments was measured in October and March each year. Leaf material had higher percent crude protein and DMD, with lower percent ADF and lignin than the inflorescence and culm. The third leaf (the youngest plant material) had the highest nutrient value of all appendages. The culm and inflorescence values were not statistically different. Growth following spring defoliation treatments produced higher percent crude protein and DMD (P<.05), with a lower percent ADF and lignin than non-treated plants in both years. This was particularly pronounced during 1986 when precipitation in late summer initiated fall growth. Growth following spring defoliation and bluebunch wheatgrass not defoliated did not produce crude protein or DMD values sufficient to meet minimum dietary maintenance requirements for elk. Fall precipitation adequate to promote fall growth occurred only in 1986. Growth after fall defoliation had the highest percent crude protein and DMD with the lowest ADF and lignin values of all vegetation sampled. However, without 3-5 cm of late summer/early fall rains, fall growth does not occur. This happened in 1987. When growth does occur in fall the quality of the growth exceeds the minimum dietary maintenance requirements for elk. Freezing and thawing of fall growth plant material had minimal effect on forage quality. There were differences (P<.05) between the monthly values for percent crude protein and ADF starting in October and ending in April. However, the percent DMD and lignin from October to April were not different (P<.05). / Graduation date: 1993

Forage availability, diets, distribution, and productivity were compared for Roosevelt elk, Cervus elaphus roosevelti, using improved (i.e. seeded, fertilized, and grazed) and untreated areas of the Oregon Coast Range. Seasonal forage availability was substantially different on 1-year-old improved and untreated clearcuts, but the differences diminished by clearcut age 4 and essentially disappeared by clearcut age 7. Elk diets, as evaluated by fecal analysis, were similar in plant species composition and DAPA concentrations on both areas. There was no significant difference in estimated calf birth weights or survival, or in pregnancy and lactation rates, kidney and metatarsal marrow fat concentrations, or breeding dates of adult cows using improved and untreated areas. Summer and winter calf ratios were similar in 7 of 8 seasons sampled. There was no significant difference in home range or core area size, and distances traveled were similar on both areas in all seasons except winter. Elk exposed to summer sheep grazing were displaced an average of 1211 m (SD = 28 m) for an average of 14 weeks (SD = 5 weeks). Elk using improved areas stayed closer to forage areas in spring, but otherwise there was no significant difference in proximity to forage. Elk from both areas demonstrated preferential use of meadows, and used other forage areas in proportion to their availability. The combined results indicated that the forage improvement practices were ineffective in producing any measurable benefits for elk. / Graduation date: 1994