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I studied sex-specific movements and habitat use of Rocky Mountain elk (Cervus elaphus nelsoni) in the Cascade Range of south-central Washington, USA, during 1992-1999. I used 3,059 relocations of 78 radiomarked elk (25 adult males, 26 subadult males, and 27 adult females). Adult males (≥5 yr) consistently migrated from summer-autumn home ranges earlier than other elk, contrary to expectations, but the timing of spring migration was similar among sex-age classes. Using compositional analysis, I found habitat use of adult and subadult (≤4 yr) male elk during winter and summer-autumn were similar at home-range and patch scales. However, use compositions for cover types and topographic features often differed between males and females. Males selected mature semi-closed forest at both scales during summer-autumn. Females demonstrated similar preferences to males at the home-range scale. I did not detect selective use of cover types at the patch scale by females during summer-autumn. I also did not detect selective use of cover types at the home-range scale by males during winter, but males selected conifer forest at the patch scale. In contrast, females selected oak (Quercus spp.) woodland and openings at the home-range scale and used cover types proportional to their availability at the patch scale during winter. All elk located their winter home ranges in relatively steep terrain, but within winter home ranges, males selected gentler slopes than females did. The effects of roads on habitat use differed among sex-age classes of elk; adult males selected summer-autumn home ranges with lower road densities and used patches much farther from roads than did subadult males (x difference = 693.8 m) and females (x difference = 827.4 m). During winter, female elk home ranges had lower road densities, and females used areas farther from roads than adult and subadult males, but differences in effect sizes were small. Data were consistent with the hypothesis that males used environments with predictably less human activity than did female elk.

Movement of Rocky Mountain elk (Cervus elaphus nelsoni) to private land in Colorado, USA, is problematic for population management because once on private land, elk are largely unavailable for harvest. We evaluated the relative effects of reducing hunter numbers and changes in opening dates of early-season hunting (archery) on elk movement to private land during a 4-year field experiment. Our study area was divided into north (NTA) and south (STA) treatment areas. Eighty adult female elk were captured and radiomarked during July 1996. From 1996 to 1999, we relocated radiomarked elk 2 times per week for a 2- to 3-month period surrounding archery season opening dates, and we classified each elk location as being on public or private land. In 1996 and 1997, NTA and STA opening dates were manipulated, and in 1998 and 1999, the number of NTA archery licenses sold was reduced approximately 50%. Using Akaike's Information Criterion (AIC) model selection to generate estimates, we found that elk movement to private land was not affected by a 50% reduction in hunter numbers. Likewise, the best AIC model exploring the mean date of elk movement to private land did not include a variable for hunter numbers treatment; the model included only an area variable. However, mean date of elk movement (±95% CI) overlapped opening day of archery season in 7 of 8 cases, indicating that elk shifted the timing of their movements to private land in response to the beginning of hunting season. Delaying archery opening day had a greater effect on retarding elk movement onto private land than reducing hunter numbers. More intense management, such as reducing hunter densities for >2 consecutive years, or decreasing hunter numbers by greater proportions, may be required to alter elk movements onto private lands compared to the more successful option of delaying archery opening day.

Mule deer (Odocoileus hemionus) and elk (Cervus elaphus nelsoni) in Colorado showed a decline in post-harvest young:female ratios during 1975-1995. One hypothesized cause of this decline in productivity is a decline in male:female ratios during the breeding period. We examined Colorado Division of Wildlife (CDOW) deer and elk population composition data obtained from helicopter surveys to see whether sex ratios explained variation in young:female ratios. Data for both deer and elk supported a response of young:100 females ratios to the male:100 females ratios during the previous year. The observed ratios were about 0.25 fawns:100 does per I buck:100 does for deer (95% CI ± 0.14) and 0.28 calves:100 cows per 1 bull:100 cows for elk (95% CI ± 0.12). However, these effects were not adequate to explain the decline in fawn:doe (1.14 fawns:100 does per year) and calf:cow ratios (0.68 calves:100 cows per year) observed during 1975-1995. Differences in the sex ratio:productivity relationship observed between populations suggest that only some areas might show an increase in young:female ratios in response to an increase in male:female ratios, and then only a small increase in young:females was predicted. We did not detect a threshold of male:female ratios for either species that precipitated a drastic decline in productivity. Based on commonly employed population composition surveys, we conclude that increasing post-season sex ratios will have little if any impact on subsequent population productivity.

We measured the grazing preference of 3 castrated male Rocky Mountain elk (Cervus elaphus nelsoni) for 2 crested (Agropyron desertorum [Fischer ex Link] Schultes), 5 thickspike (Elymus lanceolatus ssp. lanceolatus [Scribner &J.G. Smith] Gould), 3 Snake River (proposed name E. lanceolatus ssp. wawawaiensis), and 2 bluebunch wheatgrass (Pseudoroegneria spicata [Pursh] A. Love) entries. Number of bites and visits were highly correlated in early May (r2=0.77) and late May (r2=0.83). 'Critana' and 'Elbee' thickspike and 'Hycrest' and 'Nordan' crested wheatgrasses can be recommended for seedings for elk spring grazing where these grasses are adapted.

Because of the extent and cost of elk (Cervus elaphus nelsoni) damage in Colorado, we tested the repellency of MGK? Big Game Repellent (BGR), chicken eggs, coyote (Canis latrans) urine, Hinder?, Hot Sauce Animal Repellent? (Hot Sauce), Ro -pel?, and thiram on tame cow elk there from December 1990 to February 1991. At the concentrations used, coyote urine and BGR performed better than the other repellents for deterring elk from feeding on cubed alfalfa hay. Consumption of rations treated with odor repellents (BGR, chicken eggs, coyote urine, and Hinder) increased from day 1 through day 5 of the trial, but consumption of rations treated with thiram (a taste repellent) decreased. In a second trial, hungry elk consumed significantly more repellent-treated apple twigs (Malus domestica) than did elk that were maintained on an ad libitum diet. Hot Sauce, applied at 100 times (6.2%) the labeled concentration for deer (Odocoileus spp.), deterred all 9 satiated elk and 7 of 9 hungry elk from browsing on apple twigs, but the labeled concentration (0.06%) failed to deter most elk fed ad libitum and all elk when hungry. Coyote urine, at 10% and 100% concentrations, failed to deter hungry elk, but the 100% solution moderately deterred elk fed ad libitum from browsing on apple twigs. Thiram applied at the labeled concentration and at 10% of the labeled concentration for deer failed to deter any elk when hungry and most elk when fed ad libitum. In a third trial, Hot Sauce at concentrations of 0.06%, 0.20%, and 0.62% did not deter any of 9 elk fed 50% of their average daily intake, but the 2.0% and 6.2% concentrations deterred 2 and 6 elk, respectively. Hot Sauce, at concentrations of 6.2% and 12.4%, and 100% coyote urine were not phytotoxic to apple trees. Abstract: Because of the extent and cost of elk (Cervus elaphus nelsoni) damage in Colorado, we tested the repellency of MGK? Big Game Repellent (BGR), chicken eggs, coyote (Canis latrans) urine, Hinder?, Hot Sauce Animal Repellent? (Hot Sauce), Ro -pel?, and thiram on tame cow elk there from December 1990 to February 1991. At the concentrations used, coyote urine and BGR performed better than the other repellents for deterring elk from feeding on cubed alfalfa hay. Consumption of rations treated with odor repellents (BGR, chicken eggs, coyote urine, and Hinder) increased from day 1 through day 5 of the trial, but consumption of rations treated with thiram (a taste repellent) decreased. In a second trial, hungry elk consumed significantly more repellent-treated apple twigs (Malus domestica) than did elk that were maintained on an ad libitum diet. Hot Sauce, applied at 100 times (6.2%) the labeled concentration for deer (Odocoileus spp.), deterred all 9 satiated elk and 7 of 9 hungry elk from browsing on apple twigs, but the labeled concentration (0.06%) failed to deter most elk fed ad libitum and all elk when hungry. Coyote urine, at 10% and 100% concentrations, failed to deter hungry elk, but the 100% solution moderately deterred elk fed ad libitum from browsing on apple twigs. Thiram applied at the labeled concentration and at 10% of the labeled concentration for deer failed to deter any elk when hungry and most elk when fed ad libitum. In a third trial, Hot Sauce at concentrations of 0.06%, 0.20%, and 0.62% did not deter any of 9 elk fed 50% of their average daily intake, but the 2.0% and 6.2% concentrations deterred 2 and 6 elk, respectively. Hot Sauce, at concentrations of 6.2% and 12.4%, and 100% coyote urine were not phytotoxic to apple trees.

During 13 January-29 March 1988, we assessed the extent of nutritional deprivation in cow elk (Cervus elaphus nelsoni) groups on the lower, middle, and upper Northern Range and on the Madison-Firehole Range in Yellowstone National Park by 4 sequential collections and chemical analyses of urine excreted in snow (snow-urine). Associated changes in elk density and calf : cow ratios also were estimated during early and late winter or spring. Decreasing (P=0.0001) potassium : creatinine (K:C) ratios throughout winter and increased (P=0.0001) urea nitrogen : creatinine (U:C) on all 4 areas indicated progressive nutritional deprivation and increasing net catabolism of lean body tissue, respectively. These ratios also varied among the 4 sampling areas during early (P=0.0001) and late winter (P

We studied the responses of mature, bull elk (Cervus elaphus nelsoni) to repeated bugling that simulated a technique used by hunters to harvest elk. Our study was conducted on the Forbes Trinchera Ranch in southcentral Colorado during September and October 1988-89. We repeatedly approached and bugled at individually radio-collared bulls. To instill negative reinforcement, treatment bulls were harassed by the sound of a shot after bugling sessions; control bulls were not. We used a logistic regression model to test the bulls' ability to learn to avoid hunter vocalizations after repeated harassment. A model that fit the observed data included previous harassment (P = 0.030, 1988; P < 0.0001, 1989), suggesting that repeatedly harassed bulls can learn to avoid a bugling hunter. J. WILDL. MANAGE. 55(3):396-400 Several hypotheses regarding the function of bugling by bull elk have been suggested. Bulls may bugle to advertise to cows (Struhsaker 1967, Geist 1982), to bring harem members closer together (Bowyer and Kitchen 1987), or to assess the fighting ability of other bulls (Clutton-Brock and Albon 1979). During rut some bulls will respond to bugling by searching out and chasing off intruders (Geist 1982, Bowyer and Kitchen 1987); others will try to threaten the intruder with bugles of their own (Harper et al. 1967, Lincoln et al. 1970, Clutton-Brock and Albon 1979). These responses are regularly exploited by hunters during rut. Because the number and proficiency of hunters attempting to harvest bull elk during rut has increased, wildlife managers are concerned that this technique could result in an overharvest or excessive disturbance of bulls during a time of year when they are highly vulnerable. Shooting in the immediate proximity of an elk may cause it to run several kilometers (Skovlin 1982) or to move off into distant, heavily-timbered areas (Ward 1973, Wright 1983). Batcheler (1968) thought that persistent hunting in New Zealand caused a shift in habitat use and an increase in nocturnal activity. If bulls did not develop an avoidance response to hunter bugling, concern about further behavioral and physiological effects of heavy hunting pressure during the rut might be warranted. Artificial bugling by hunters represents a unique type of disturbance, the effects of which have not been determined. Our objective was to determine whether individual bulls learn to cease responding when they are repeatedly harassed after approaching a simulated bugle. We administered the aversive stimulus of firing a blank from a revolver to treatment bulls to experimentally test bull

Winter diet quality of elk (Cervus elaphus nelsoni) was studied in the Jemez Mountains, New Mexico, during January-April 1980 on a recently-burned montane area (BURN) and an unburned upper montane area (BACA). Grasses dominated diets in the BURN, but nearly equal proportions of browse and grass were eaten in the BACA. Botanical composition of diets did not vary during the study at either site. Crude protein and in vitro digestible organic matter (IVDOM) in forages did not differ between locations. Grasses were more digestible than browse, but crude protein content was similar between forage classes. IVDOM and protein increased significantly in grasses with advancing season, but not in browse. Dietary protein ranged from 3.5 to 7.2% in the BURN and from 4.7 to 7.5% in the BACA and was consistently superior in the BACA. Diet IVDOM in the BURN surpassed that in the BACA. Increases in diet quality were correlated with changes in quality of grasses ingested by elk. Forage quality was more variable than was diet quality, indicating the ability of elk to maintain relatively constant diet quality when confronted with large fluctuations in forage quality. 1 figure, 3 tables.

La pression de chasse comme facteur influencant la date de conception chez les clans des Montagnes Rocheuses

Digestive capabilities of elk (Cervus elaphus nelsoni) were determined during 15 feeding trials of singleand multiple-component rations. These results were compared to digestibilities by whitetailed deer (Odocoileus virginianus). Neutral-detergent-solubles (NDS) digestible amount was linearly related to feed content in both elk and deer. Soluble phenolics depressed NDS digestibility but not fiber digestibility. Fiber digestibility decreased curvilinearly with increasing lignin-cutin content in both elk and deer. Elk digested more of the less lignified cell walls than did deer. Equations for estimating drymatter and energy digestibility in both elk and deer are presented. J. WILDL. MANAGE. 46(1):22-29 The understanding of digestion forms an important link in relating the nutritional requirements of wildlife to their available food resources. Because it is impossible to measure the in vivo digestibilities of all forages and combinations consumed by free-ranging ungulates, digestibilities ultimately must be predicted from either summative equations developed from the comparison of feed composition and in vivo digestibility, or in vitro trials if the relationship between in vivo and in vitro digestibilities is known. The estimation of digestibilities must be species specific if larger ruminants digest feed more completely than do smaller species (Hungate et al. 1959). Because digestion measurements for elk have been limited to only a few feeds (Thorne, unpubl. rep., Wyo. Fed. Aid Proj., FW-3R-20, 1973; Westra 1978), summative equations and in vivo-in vitro comparisons have not been previously generated. In addition, earlier summative equations for deer (Robbins et al. 1975) must be reevaluated in light of recent analytical changes (Van Soest and Robertson 1980, Mould and Robbins 1981b). Consequently, the following study was undertaken to (1) compare the digestive capabilities of elk and white-tailed deer, (2) evaluate the role of various feed constituents in reducing digestive efficiencies, (3) generate summative equations for estimating digestibility in the 2 ungulates, and (4) compare in vivo and in vitro dry-matter digestibilities. We acknowledge support from the Washington Department of Game, National Science Foundation (DEB 7624329), and Washington State University. The assistance of M. Reisenauer, B. DeWaard, A. Pfister, M. Radenberg, S. Knick, and D. K. Hulbert is appreciated.

Nutrient intake and utilization are fundamental processes linking wild ruminants to their food supply. Adaptations in body size, digestive physiology, and metabolic requirements influence the food niches and habitat requirements of these animals (Hoffman 1973, Kay et al. 1980, Hanley 1982). Studies of trophic relations and digestive morphology of wild ungulates suggest that larger ruminants are more efficient than smaller ones in digesting fibrous forages (Bell 1970, Prins and Geelen 1971, Short et al. 1974, Giesecke and Van Gylswyk 1975, Jarman and Sinclair 1979, Demment and Van Soest 1981, Mould and Robbins 1982). Few controlled feeding experiments have been conducted on wild ruminants to test this hypothesis (Arman and Hopcraft 1975, Mould and Robbins 1982). Although mule deer (Odocoileus hemionus hemionus) and elk (Cervus elaphus nelsoni) have both been categorized as "mixed feeders" (Kay et al. 1980:741, Hobbs et al. 1983), studies of their diet selection and digestive morphology suggest they may utilize foods differently (Short et al. 1965, Church and Hines 1978, Mould and Robbins 1982, Hobbs et al. 1983). We compared the digestive capability of a large ruminant (elk) and a small ruminant (mule deer) consuming grass hay and related these digestibilities to those predicted from in vitro measurements.

Examen des correlations entre precipitations cumulatives et temperatures estivales d'une part, choix de l'habitat par Cervus elaphus nelsoni d'autre part (nord des Garnet Mountains, Montana)