Eastern Beaufort Sea beluga (Delphinapterus leucas) body condition indicators for monitoring the Tarium Niryutait Marine Protected Area

• Main Author: MacMillan, Kathleen
• Other Authors: Loseto, Lisa (Environment and Geography) Peyton, Jonathan (Environmental and Geography), Hanson, Mark (Environment and Geography) Roth, James (Biological Sciences)
• Format: Master Thesis
• Language: English
• Published: 2019
• Subjects: Beluga; Body condition; Indicator; Marine protected areas; Arctic; Monitoring; Pacific; Beaufort Sea; Beluga*; Delphinapterus leucas; Inuvialuit; Sea ice
• Online Access: http://hdl.handle.net/1993/33689

Two body condition indicators, blubber thickness and maximal half-girth measurements, were evaluated for use to monitor the health of Eastern Beaufort Sea beluga (Delphinapterus leucas) in the Tarium Niryutait Marine Protected Area (TN MPA). Beluga body condition metrics collected from the community-based beluga monitoring program in the Inuvialuit Settlement Region from 2000-2015 were assessed. Body condition indicators based on the predicted values and residuals of fitted linear models for blubber thickness and girth were developed to account for variation in age, size, location, and timing of harvest. Statistically significant differences in condition were detected between regions of the TN MPA for three of the condition indices. The male blubber thickness indicator was found to increase during the summer harvest season. Long-term temporal analyses found that both girth indicators led the trends in both blubber thickness indicators. Lastly, two large-scale climatic variability metrics, Pacific Decadal Oscillation and sea ice minimum, were significantly negatively correlated to body condition trends. This research provides key recommendations for the TN MPA co-management agencies on the use of body condition indicators. February 2019