Sydney Goward

Topic

Using remote camera traps to monitor population demographics and community ecology of divii (Dall’s sheep): Part of a community-based monitoring program in the Northern Richardson Mountains, NT

School of Environmental Studies

Date & location

• Monday, April 8, 2024

• 1:00 P.M.

• David Turpin Building

• Room B255

Reviewers

Supervisory Committee

• Dr. Jason Fisher, School of Environmental Studies, University of Victoria (Co-Supervisor)

• Dr. Trevor Lantz, School of Environmental Studies, UVic (Co-Supervisor) 

External Examiner

• Dr. Chris Darimont, Department of Geography, University of Victoria 

Chair of Oral Examination

• Dr. Ulrich Mueller, Department of Psychology, UVic

   

Abstract

The warming Arctic is undergoing rapid ecological change, influencing wildlife populations, mammal community interactions, and ultimately, the persistence of many species. Collecting the species monitoring data required for sound stewardship decisions in these remote areas is a major challenge. Remote wildlife cameras, facilitated through community-based monitoring programs, offer a solution to provide this critical data. In this thesis, I employ novel methods in remote camera trapping as part of a community-based monitoring program to investigate Dall’s sheep population demography and predator-prey dynamics with grizzly bears. In Chapter 2, I explore the ability of remote wildlife cameras to estimate population demographics (lamb:nursery, ram:nursery, and ram classification proportions), as compared to currently standardized aerial surveys. These metrics are imperative to assessing population status and predicting population trends. I found that camera data, accumulated sufficiently through time and discretized in appropriate biological seasons produced reliable lamb:nursery, ram:nursery, and ram classification proportions comparable to those obtained from aerial surveys, and produced similar population status trends between the two methods. To my knowledge, this is the first study employing remote cameras to estimate productivity (lamb:nursery ratio) and adult sex ratios in a wild, un-marked sheep population, and marks a significant advancement in wildlife monitoring with remote cameras. In Chapter 3, I examine the temporal coexistence of Dall’s sheep and grizzly bears, in a core habitat area, at different times of the year. I used remote camera data to derive a time-to-event model investigating if and how grizzly bears are tracking nursery groups and ram bands. I also evaluated the differences and similarities in diel activity patterns between the species to estimate temporal niche partitioning. I found clear temporal segregation of nursery groups and grizzly bears, and showed that grizzly bears were more closely tracking nursery groups than ram bands, especially early in the spring when lambs are most vulnerable to predation. The results indicate that camera traps can yield fine resolution insights into predator-prey relationships. This study provides a new method to monitor Dall’s sheep population demography, as well as new information on Dall’s sheep and grizzly bear relationships. Incorporating a remote camera system into wildlife monitoring programs allows for a more comprehensive examination of demography, while fostering an opportunity to explore further questions related to community-based monitoring and management.