Bachelor of Science
School or Department
Faculty Mentor Department
Dr. Mike Mitchell; Dr. Joshua Nowak; Jesse Whittington
Elk, juvenile recruitment, occupancy, survival, remote camera
Juvenile recruitment is a key parameter in understanding ungulate population dynamics. Traditional methods in population composition surveys, such as estimating young: adult-female ratio’s, can be precluded by cost, safety, and feasibility. The use of remote cameras provides a potentially cutting-edge tool to apply to wildlife population estimation techniques. While the prevalence of remote cameras in ungulate studies has increased, few studies have used cameras to estimate vital rates, such as recruitment or survival. Here, we tested the potential of remote cameras to estimate calf: cow ratios and calf survival of elk (Cervus elaphus) using the Royle-Nichols (2003) occupancy model. Using the Royle-Nichols (2003) model, data collected from cameras on unmarked individuals can estimate detection probability and abundance. We compared camera-based estimates of calf: cow ratio to traditional ground-based estimates obtained from group classification surveys. We test this approach in a partially migratory elk population at the Ya Ha Tinda (YHT) Ranch, Alberta, Canada. We deployed cameras (n=44), across the YHT, a working horse ranch and important elk winter range. We created a Royle-Nichols occupancy model for female and young-of-year elk, estimating abundance of respective age classes for a 110-day sampling interval between 15 May – 1 September 2018. We estimated calf survival by comparing the abundance estimates of calves between 7 primary sampling periods and determined the effect of abiotic, biotic and anthropogenic covariates on detection probability and abundance. Our camera-based ratio results made biological sense; following expected trends in detection variability, peak calf abundance, and declining ratios associated with neonatal mortality. We then compared the estimates of calf survival and group composition to those of traditional field estimates collected in the same time period. We conducted a Pearson correlation test and found an r=0.426 correlation between our camera-based and ground observations of calf:cow ratio. Although the correlation was moderate, ground-based estimates were biased due to sightability of hiding calves. Thus, our results demonstrate the utility of using remote cameras to derive important parameters for understanding ungulate population dynamics.
Honors College Research Project
GLI Capstone Project
Hessami, Mateen A., "Estimating Juvenile Recruitment of Elk in an Occupancy Modeling Framework" (2019). Undergraduate Theses and Professional Papers. 252.
© Copyright 2019 Mateen A. Hessami