Our new project assessing the body condition of the “Sounder” gray whales is progressing well. SR3’s Dr. Holly Fearnbach is collaborating with Dr. John Durban (Southall Environmental Associates) and John Calambokidis (Cascadia Research Collective) to monitor changes in body condition of this group of whales that stopover during migration to feed in North Puget Sound. We are using a remotely controlled drone to collect high resolution aerial images to measure size and body condition to assess health changes, and also collecting blow samples to assess respiratory health. By collaborating with Cascadia Research Collective, we are able to link our measurements to track changes in condition of known individuals. So far, we have imaged 9 different whales, with repeat images of 4 of these whales between March and April. It is clear in the photos below that some of these whales markedly improved in body condition since first arriving to feed. This rapid improvement highlights the importance of Puget Sound as a stopover location where the “Sounder” gray whales fatten up on ghost shrimp (more information). We will continue to assess their nutritional health until early summer when the whales resume their northbound migration to Arctic feeding grounds. Results from this study will provide important information on the body condition and health of gray whales during the current Unusual Mortality Event. This research was conducted by two scientists from the same household, such that social distancing and isolation requirements were safely met.
Aerial images of two “Sounder” gray whales (CRC-49, “Patch”; CRC-21, “Shackleton”) taken on March 19th and April 6th, 2020. Changes in body condition are already evident, with both whales appearing fatter in April. Images were collected non-invasively using a remotely-controlled hexacopter drone flown at >150ft over the whales under NMFS research permit 19091. Photo by Holly Fearnbach (SR3) and John Durban (SEA).