Abstract
Large whales are hard to examine at sea. Here we describe a perspective to enable a better understanding of their individual condition and health. We used aerial photogrammetry to study growth of endangered North Atlantic right whales (NARW) (Eubalaena glacialis) in the Bay of Fundy Canada in 2000–2002 (manned fixed wing aircraft) and Cape Cod Bay in 2016 (Unmanned Aerial System, UAS).1,2 Matching to the NARW catalog revealed 33 distinct individuals in the 2016 images, with five of these also represented in the earlier dataset. Updated length-at-age relationships revealed that whales growing in the last 15 years are generally smaller than those of the same ages measured in the early 2000s; this was most dramatic for four juveniles aged between 2 and 6 that were clearly below the expected growth curve.3 In contrast, older whales (>20 years) had estimated adult sizes consistent with the previous dataset, including similar measurements of whales represented in both sets. Body width to length ratios indicated a potential reduction in body condition in the recent samples. Using a UAS we collected and analyzed blow samples from humpback and right whales for respiratory microbiome analysis.4 Concurrently, using an infrared camera we acquired overhead thermal and RGB video of the head including the open blowhole. We measured core temperature at the base of the open blowhole, and the changes in the size of the blowhole during surfacing sequences.5 Thus, we are able to acquire short and long-term indices of health and growth.
Acknowledgements
Study conducted under NOAA Permit 17355-01. Funded by Woods Hole Oceanographic Institution Independent Research & Development Program and NOAA CINAR #NA14OAR4320158.
* Presenting author
Literature Cited
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