Humpbacks feeding in Nicaragua prompt a new body-condition study
Observations of adult humpback whales feeding in their Nicaraguan breeding grounds have prompted a new three-year project. Researcher Joëlle De Weerdt plans to combine drone images with tissue samples to follow body condition and feeding locations. The interview describes the research programme and its hypotheses, rather than completed findings about the benefits of feeding.
Science··Evening
Adults fed in a breeding area
Humpback whales usually build fat reserves in feeding grounds before migrating to tropical breeding waters. In Nicaragua’s Pacific coastal zone, researcher Joëlle De Weerdt observed adults feeding where the usual pattern involves a prolonged fast. She has begun a three-year project at the University of Liège in Belgium, funded by the scientific research fund FNRS, to investigate that behaviour. Daily Science’s interview describes observations and planned research rather than a completed new study.[1]
Drone images are planned to track body condition
The project focuses on whales feeding along the northwestern United States before travelling to Nicaragua to breed from November to April. De Weerdt plans to photograph them from above with drones throughout their stay. Photogrammetry, measurement from images, is intended to follow changes in body condition across the season. Whether local feeding helps preserve or improve that condition is a hypothesis the project aims to test.[1]
Tissue samples are intended to trace feeding locations
Skin and blubber samples are planned to complement the images. Carbon and nitrogen isotope signatures in prey differ between the two feeding regions, offering a way to investigate where the whales ate. Genetic analyses are intended to identify sex and family relationships, while epigenetic analysis is planned to estimate age. These measurements could test whether the observed feeding strategy is shared across sexes or related animals; results are still pending.[1]
