MONITORING AND ASSESSMENT OF WOLF-UNGULATE INTERACTIONS AND TRENDS WITHIN THE GREATER YELLOWSTONE ECOSYSTEM
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Ken Hamlin
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Study Areas and Populations--Gallatin Canyon
| The Gallatin Canyon (GC) site consists of two subsites that cover 125 km2 in four drainages (Porcupine [30 km2], Taylor Fork [56 km2], Tepee [13 km2] and Daly [26 km2]), on a combination of National Forest and state land. Valley bottoms are primarily sagebrush grassland and grassland with small riparian zones. Coniferous forest and small meadows dominate the slopes above. Elevation runs from 1975 m ASL to 2432 m ASL. The GC site has held between 1214 and 3028 elk over the past seven decades, holding relatively stable around the long-term average of 1725 ± 63 (SE) animals (13.7 elk/km2). Elk comprise >90% of the ungulate community, usually in small groups (mean = 18.9 elk ± 2.2 SE, max = 176 elk: counts of 414 ungulate groups in winter 2000-01). Moose, mule deer and white tailed deer (Odocoileus virginiana) also use the GC site, at densities much lower than elk (total of 50 individuals in 23 groups out of 414 groups counted). Elk move freely between the four drainages, but elk density is very low in the steep, rocky cliffs between the subsites. Policies regulating human hunting on the GC site have varied substantially, but hunting has generally been used to regulate herd size and reduce the impact of browsing on woody plant regeneration (Lovaas 1970; K. Alt, pers. comm). Few elk are on the GC site during the fall general hunting season, but 80 licenses are issued for a late-season hunt, with an average 63% success. Because calf recruitment has declined recently, these late-season permits have been reduced in number from about 500 issued previously. |
Gallatin Canyon (top) and Daly Creek (bottom) study areas. Photos © John Winnie, Jr.
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The
GC site is used by the Chief Joseph pack, which included 12 wolves in the winter
of 2000/01. This pack has one of the largest home ranges in the GYA (Smith et
al. 2000), and moves frequently from the GC site to the EM site and other areas
that are quite difficult to reach on the ground. During a field season of 3
months, we recorded 24 kills in 283 wolf-days (8.48 
kills/100 wolf-days). The
Chief Joseph pack is currently denning on the GC site. Two females established
dens separated by 3.1 km, but the den occupied by a subordinate female was
abandoned after a month. We do not know if her pups died or were transferred to
the alpha female's den.
The intermittent use of this site by wolves will allow for detailed analysis of changes in anti-predator behavior by elk (herd sizes and configurations, habitat selection, vigilance, feeding rates, diurnal activity patterns) under varying risk of predation. With respect to major variables likely to affect wolf-elk predation, this site combines public land, human hunting pressure, intermittent use by wolves, partially migratory elk herd at moderate/high (and stable) density, small elk groups, and heavy snow.
Research Projects in the Gallatin Canyon Site:
--Wolf-ungulate dynamics in upper Gallatin Canyon--John Winnie, Ph.D. candidate
