Migratory destinations and spatial structuring of humpback whales (Megaptera novaeangliae) wintering off Nicaragua

• Published in: Scientific Reports
• Main Authors: Joëlle De Weerdt, Aldo S. Pacheco, John Calambokidis, Melvin Castaneda, Ted Cheeseman, Astrid Frisch-Jordán, Frank Garita Alpízar, Craig Hayslip, Pamela Martínez-Loustalot, Daniel M. Palacios, Ester Quintana-Rizzo, Nicola Ransome, Jorge Urbán Ramírez, Phillip Clapham, Tom Van der Stocken
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Portfolio 2023
• Subjects: Medicine; R; Science; Q; Megaptera novaeangliae
• Online Access: https://doi.org/10.1038/s41598-023-41923-7; https://doaj.org/article/8b343dfa43af47e2a404bd4d27342482

Abstract Understanding the migratory patterns of large whales is of conservation importance, especially in identifying threats to specific populations. Migration ecology, including migratory destinations, movements and site fidelity for humpback whales (Megaptera novaeangliae) remain poorly studied in parts of the range of the Central America population, considered endangered under the United States Endangered Species Act. This study aimed to investigate the migratory destinations of humpback whales sighted at two study sites in Nicaragua, which are part of the Central America population. A ten-year photographic database of humpback whales observed off Nicaragua was combined with citizen science contributions and sightings from dedicated research programs. The resulting image collection was compared with available historical photo identifications and databases using an automated image recognition algorithm. This approach yielded 36 years of photographic identification totaling 431 recaptures in Nicaragua (2006–2008 and 2016–2021) and 2539 recaptures (1986–2020) in both feeding and breeding grounds of 176 unique individuals sighted in Nicaragua. Our results showed that photo-identified whales were recaptured between October and April in breeding grounds and year-round in feeding grounds between British Columbia and California, with peak recaptures between June and October. Our study provided first-time evidence on fine-scale site affinity of individual humpback whales within Nicaraguan waters and to other breeding and feeding grounds.