Banff Moose Ecology Project

Project Field Supervisor - Contract - 1994 to 1997

Background

Moose (Alces alces), were relatively common in the Bow valley of Banff National Park in the 1940’s through the 1960’s 1. Their numbers began a rapid decline during the 1970's and 1980's 2. The decline continued to the point where sightings in the Bow River Valley during annual aerial and ground surveys became rare between 1985 and 1993 3.

In 1994, concerns over the decline in moose numbers coupled with the fact that the current status of the population was unknown, Banff National Park initiated a moose research program 3.

Project Objectives

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

Capture and Monitoring

  • Capture, mark individuals for visual identification, ear-tags, combination visual/radio collars.
  • Daily intensive road/ground searches, weekly multi-species telemetry flight rounds.
  • Age and sex classification of unmarked individuals.
  • Location and recovery of transmitters on mortality.

Population Parameters

  • Yearly combined aerial survey/capture sessions, during fall rut and mid-winter.
  • Yearly population estimates, pre-calving (survival), post-calving (productivity).
  • Productivity, individual reproductive success and survival.
  • Timing and causes of mortality.

Calf Surveys

  • Yearly, aerial surveys, May 20 – June 5.
  • Timing and locations of parturition (birth), site fidelity.
  • Sex of new calves (ratios), abandonment.

Movements and Habitat Use

  • Identify movement patterns, corridors and critical habitats.
  • Assess forage quality and quantity.
  • Assess the interaction between moose, elk and other ungulates.
  • Assess the interaction between moose, wolves and other large predators.

Results

The Banff Moose Ecology Project began fieldwork in early March of 1994. Wildlife Technical Services was contracted to coordinate, supervise and conduct the fieldwork portions of the project from startup to completion of fieldwork in December of 1998.

Moose Captures

  • 45 adult moose (22 female, 23 male) captured and radio-collared.
  • 37 chemically immobilized, 8 net gun restrained, all helicopter assisted.
  • Immobilization, IM injection of carfentanil/xylazine hydrochloride, reversal, IM injection of naltrexone.

Moose Population Status

There was no definable Bow Valley population but rather a constant trickle of dispersing individuals arriving in the valley from adjacent watersheds. Once in the valley an animal's life expectancy was under 6 months.

The reasons for the decline are complex involving a variety of factors but simply put, over time, the populations' mortality exceeded its recruitment. Past, recent and ongoing events contributing to the decline including:

  • Long-term habitat loss via forest encroachment, fire suppression.
  • Increase in prevalence of giant liver fluke (Fascioloides magma) infection, a parasite hosted and shed by elk, but harmful to infected moose.
  • Increasing elk density in the central Bow valley.
  • Increasing highway and railway mortality
  • Recent wolf re-colonization (1980's) with a corresponding increase in predation.

Moose Population Parameters

  • Mean annual population estimate of 57 (48 – 66, 95% C.I.).
  • 76 mortalities, 39 females (25 ad, 5 yl, 9 yoy), 30 males (25 ad, 1 yl, 4 yoy) and 7 unk..
  • 27 predation (24 wolf, 2 grizzly bear, 1 unk.), 5 railway, 4 malnutrition, 2 highway, 2 hunting and 12 unk..
  • 33 of 45 radio collared moose had died by March of 1999.
  • 19 predation (17 wolf, 2 grizzly bear), 6 unk., 3 malnutrition, 2 highway, 2 hunting, 1 ceacal torsion.
  • Mean annual survival rate 71% (64 - 82%, 95% C.I.).
  • Mean annual calf production 67%
  • Calf survival to 1yr 23%.

Footnotes

1. Holroyd, G.L. and Van Tighem, K.J. 1983. Ecological (biohpysical) land classification of Banff and Jasper National Parks. Vol. III: Wildlife Inventory. Environment Canada, Canadian Wildlife Service, Edmonton.

2. Woods, J.G. 1990. Effectiveness of fences and underpasses on the Tran-Canada Highway and their impact on ungulate populations in Banff National Park, Alberta. Canadian Parks Service, Calgary.

3. 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.