Tyler Dale Hopkins Jessen
-
BSc (University of California at Santa Cruz, 2013)
-
BA (University of California at Santa Cruz, 2013)
-
MSc (University of Calgary, 2017)
Topic
A multi-method approach to studying a cryptic species: mountain goats in Kitasoo Xai鈥檟ais territory
Department of Geography
Date & location
-
Thursday, December 11, 2025
-
10:00 A.M.
-
David Turpin Building
Reviewers
Supervisory Committee
-
Dr. Chris Darimont, Department of Geography, 樱花影视 (Supervisor)
-
Dr. Paul Paquet, Department of Geography, UVic (Member)
-
Dr. Cole Burton, Department of Foresty, UBC (Outside Member)
External Examiner
-
Dr. Ryan Brook, Agriculture and Bioresources, University of Saskatchewan
Chair of Oral Examination
- Dr. Ibrahim Numanagic, Department of Computer Science, UVic
Abstract
Biodiversity conservation depends on linking ecological theory with applied monitoring and management. This challenge is particularly difficult for cryptic species that inhabit remote areas, where access and available data are limited. Yet such species can be of significant ecological, economic, and cultural value. By using multiple data sources, my dissertation confronts these challenges to provide an assessment of the population trends and habitat use of mountain goats (Oreamnos americanus) inhabiting the central coast of British Columbia (BC), Canada. This work begins with a synthesis and prospectus of the varied contributions of Indigenous Knowledge (IK) to ecology and evolution (Chapter 2). Although often discounted in the past, IK is increasingly contributing to the understandings of science, from the conceptualization of hypotheses, to the design of field methods, to the interpretation of results. Owing to the historically fraught relationship between western science and Indigenous peoples, the work also provides guidance for researchers to ensure that the processes and outcomes of collaborative research adhere to ethical standards, as defined by Indigenous peoples themselves. In Chapter 3, I apply this framework to a conservation assessment of a population of mountain goats residing in Kitasoo Xai’xais (KX) Territory, where scientific data were absent. Based on interview data from local land-users, observations of mountain goats declined precipitously from 1980 to 2019. Aerial surveys in 2019 and 2020 revealed a low-density population (mean = 0.25, SD = 0.12 goats/km2), typical of the coastal range of mountain goats. Lastly, provincial kill data (1980–2018) showed that, province-wide, goat kills per hunter/day declined among resident hunters in both coastal and interior BC. Together, these data suggest that coastal goats are likely declining in abundance and/or shifting in distribution, both of which threaten the long-standing relationship between people and mountain goats in the area. In Chapter 4, I examined intrapopulation variation in the space use of mountain goats in KX territory, specifically the differences between groups of mountain goats with kids and those without (typically solitary males). Using multi-state occupancy models derived from aerial surveys, I found that mountain goats use higher elevation areas, and that nanny groups with kids preferentially used areas of high terrain ruggedness. These results are consistent with foraging and predation-risk theory that suggest that reproductive groups trade areas with better forage for areas with greater security. More generally, our results show that considering sex- and age-specific variation in space use is important for the management of mountain goats, including for delineating spatial protections and hunting prescriptions. Collectively, my dissertation shows that coastal mountain goats are likely to be sensitive to human and natural disturbances, and that existing management strategies should consider age- and sex- composition as well as intrapopulation variation in space use. More broadly, this research demonstrates how disparate data sources and methodologies may be leveraged to elucidate trends in the distribution, abundance and behaviour of wildlife that present practical challenges to researchers and managers.