1. The Arctic is experiencing change driven by both climate change and anthropogenic change. How these changes will either directly or indirectly effect or impact the Eastern Beaufort Sea Beluga whales remains unknown, however developing a means to monitor or assess stress will provide a benchmark and guidance for conservation and management.
2. In this study we examined a common measure of physiological stress, cortisol, in blood and blubber to evaluate its use as an indicator of stress. We assessed levels of cortisol and compared them to circulating levels of organic contaminants. We then used findings to make recommendations towards the use of cortisol a long term monitoring indicator of stress in beluga.
3. Cortisol levels ranged among tissues with levels in blood being the highest likely reflecting acute stress (e.g. being chased during the hunt). Higher cortisol levels in the inner blubber suggest this tissue more closely reflects circulating levels relative to the middle and outer blubber. Overall cortisol levels in harvested beluga were similar to captive belugas at a ‘resting’ state indicating Eastern Beaufort Sea beluga whales are under low stress.
4. Cortisol levels in outer blubber tissue (near skin) will make for an ideal indicator for monitoring chronic stress. . The lack of relationship between levels of cortisol and contaminants, a known physiological stressor, suggests current contaminant burden in beluga may not be having a significant impact on overall stress.
Read the full paper in Arctic Science: Cortisol levels in beluga whales (Delphinapterus leucas): Setting a benchmark for Marine Protected Area monitoring
Corresponding author: Lisa Loseto, email@example.com