9:00 am - 10:00 am
Location: 849 General Services Building
Event details: A graduate exam seminar is a presentation of the student’s final research project for their degree.
This is an ALES MSc Final Exam Seminar by Emily Cicon. This seminar is open to the general public to attend.
MSc with Dr. Scott Nielsen
Thesis Topic: Surrogacy and Umbrella Effects of Grizzly Bears on Songbirds is Scale Dependent
The consideration of different spatial scales in ecological studies, including assessments of surrogacy, is often suggested, but less commonly executed. Species utilize their environments at many spatial scales; therefore, the relationships between species including surrogate relationships, will vary depending on the scale of analysis. Here I study the potential for grizzly bears to act as a surrogate for songbird conservation in Alberta across three spatial scales: (1) the broad-scale umbrella effect that uses the scale of individual home ranges of bears, (2) an intermediate scale that uses seasonal patch-level resource selection function models (maps) to index local use (avoidance to selection) of habitats by grizzlies within a region, and (3) the localized scale that uses individual bear telemetry locations with known activity. The relationship between grizzly bears and songbird diversity changed over the three spatial scales examined – with the strongest effects observed at the largest scale and little to no relationship at the intermediate and localized scales, respectively. This emphasizes the importance of spatial scale in surrogacy studies. As well as testing grizzly bears more intensively, I also tested the idea that flagship species are equivocal to umbrella species by comparing grizzly bears to two other well-known flagship species in Canada – the greater sage-grouse and woodland caribou. Grizzly bears were found to outperform the other candidate species at the largest umbrella scale in Alberta – illustrating that a flagship can also be an umbrella species, but not in all cases. I also demonstrate that when scale is kept constant across space, geographic variation significantly affects the potential for a signal in surrogacy (e.g. not all areas of grizzly bear range are equally effective in being a surrogate).
A primary motivation for using surrogate species is to simplify conservation action – using the management of one species’ to guide the conservation of many. While this appears to be a theoretically simple idea, it has proved to be contentious in the literature and its efficacy circumstantially difficult to predict. The research presented in this study contributes to knowledge on the applications of surrogacy – helping to outline the circumstances and methods where the management technique will be the most or least effective.