Banff Elk Ecology Project

Project Field Supervisor - Contract - 1997 to 1999

Background

During the period 1990-1996, concerns grew over increasing elk (Cervus canadensis) numbers in and around the town of Banff, Alberta and corresponding increases in elk/human conflict as well as declining elk numbers in the western Bow Valley 1. These concerns prompted Banff National Park to initiate the Banff Bow Valley Elk Ecology Project in 1997 2.

Project Objectives

To assess the status of the elk population within the Bow River watershed of Banff National Park. Key elements included:

Capture and Monitoring

  • Capture, mark individuals for visual identification, node specific ear-tags and radio-collars.
  • Daily intensive road/ground searches, weekly censuses, weekly multi-species telemetry flights.
  • Location and recovery of transmitters on mortality.

Assess Key Population Parameters

  • Elk zone and node identification.
  • Yearly population totals, pre-calving (survival) and post-calving (productivity).
  • Productivity, individual reproductive success and survival.
  • Timing and causes of mortality.

Calving Surveys

  • Yearly, aerial/ground survey, May 20 – June 5.
  • Timing and locations of parturition (birth).
  • Sex of new calves (ratios), abandonment.

Movements and Habitat Use

  • Identify movement patterns, corridors and critical habitats.
  • Assess forage quality and quantity.
  • Assess interaction between elk, wolves, other ungulates and other large predators.
  • Assess competition for and impact on forage by elk, moose and other ungulates.

Results

The Banff Elk Ecology Project began fieldwork in January of 1997. Wildlife Technical Services was contracted to coordinate, supervise and conduct the fieldwork from startup to completion of fieldwork in December 1999.

Elk Captures

  • 149 elk captured and marked, 73 radio-collared (47 ADF, 1 YLF, 22 F and 23 M calves).
  • Captures, corral trap or chemical immobilization, via ground stalking or helicopter.
  • Immobilization, IM injection carfentanil and xylazine/hydrochloride or ketamine and xylazine/hydrochloride, reversal IM injection naltrexone and yohimbine or antagonil respectively.

Elk Population Parameters

The Bow Valley was divided into 3 zones (eastern, central and western) and 2 distinct sub-populations (Urban and Rural) based on elk, wolves and human density and their behavior. Urban elk were habituated to human presence, utilizing the town site and its periphery. Rural elk were non-habituated; inhabit areas of the valley, east, north and west of town. Elk were found to exist in discrete sub-herd units with little or no interchange and differing rates of mortality.

Population Estimates

In 1983, elk in all three zones had relatively similar population estimates, densities and rates of railroad and highway mortality. Wolves were not present. By 1986-87, wolf re-colonization was well under way and the TCH twinning project phase I & II had been completed.

In the eastern zone, the 1984/85 population estimate was N=139. The 1997/98 population estimate was N=72. Elk numbers began stabilizing with the completion of the highway twinning project phase I & II in 1987. However, increasing highway kills at the east end of the twinning segment fencing combined with increasing railway mortality and wolf predation from re-established packs, lead to a continued decline in elk numbers by 1995.

In the central zone (Banff town site), the1984/85 the population estimate was N=223. The 1997/98 population estimate was N=455. Elk numbers increased and highway mortality was eliminated with the completion of the highway twinning project phase I & II in 1987. Human use was highest in this zone, which excluded predators, greatly reducing predation. The result, productivity and survival rates were high corresponding with increases in elk numbers.

In the western zone, the 1984/85 the population estimate was N=411. In 1997/98 there were exactly 40 elk left. The numbers of elk have been in a constant rate of decline. Highway mortality at the west end of the twinning segment fencing remained high, railway kills continued and wolf pack kills increased into the mid 1990's.

Mortality

  • 16 of 73 radio-collared elk died (7 urban elk, 9 rural elk), 8 predation (6 wolf, 2 cougar), 3 highway, 2 railway, 1 drowning and 2 unknown.

Survival

  • Urban elk, finite survival of 69% (annual range 50-88), calf production averaged 82% and calf survival to 1year averaged 86%.
  • Rural elk, finite survival of 51% (annual range 42-79%), calf production averaged 72% and calf survival to 1 year averaged 55%.

Footnotes

1. Hurd, T.E. 1999. Factors limiting moose numbers and their interactions with elk and wolves in the Central Rocky Mountains, Canada. Masters Thesis. University of British Columbia. Vancouver.

2. Mckenzie, J. 2001. The Demographic and Nutritional Benefits of Urban Habitat Use by Elk. Masters Thesis. University of Guelph.