Environmental drivers of persistent humpback whale Megaptera novaeangliae feeding events in a Mexican breeding area
Marine ecology. Progress series (Halstenbek), Vol.726, pp.161-179
11/01/2024
1
Humpback whales Megaptera novaeangliae typically fast for several months in low-latitude breeding areas. Here we report on persistent feeding events during 5 wintering seasons between 2013 and 2020 in a known upwelling region of Banderas Bay of the mainland Mexico breeding area. In total, there were 76 unique feeding events documented (group size = 1 to similar to 100 individuals), involving 201 photo-identified whales, of which 18 were documented feeding in multiple years. The most prolific years of documented feeding in 2017 and 2018 (based on number of reports/individuals photo-identified feeding) followed the strongest marine heatwave ever recorded in the North Pacific. Whales documented feeding in Banderas Bay had significantly shorter mean sighting histories (2.3 yr) than a non-feeding sample (8.7 yr) and were reported to be of small size, suggesting they were predominantly younger whales. Most high-latitude recaptures of Banderas Bay feeding whales were in more northern North Pacific feeding grounds (50.8% were resighted in Russia, Alaska, and northern British Colombia, Canada). A binomial general linear model revealed a significant relationship between the probability of whales feeding in Banderas Bay and sea surface temperature (SST). Specifically, feeding consistently occurred in years of lower than average winter SST (<25 degrees C), associated with La Nina years of the El Nino Southern Oscillation (ENSO). We conclude that feeding of humpback whales is now a predictable occurrence in the upwelling region of Banderas Bay in years that ENSO fluctuations lead to lower regional SST. The magnitude of several years of low-latitude feeding events reported here was likely influenced by climate change induced marine heatwaves that occurred during the study period.
- Environmental drivers of persistent humpback whale Megaptera novaeangliae feeding events in a Mexican breeding area
- Nicola Ransome - Murdoch UniversityAstrid Frisch-Jordan - Centro de Estudios Universitarios ArkosTed Cheeseman - Southern Cross UniversityJohn Calambokidis - Cascadia Research CollectiveAlice Kew - La Orca Sayulita, Sayulita 63728, Nayarit, MexicoOlga Titova - Severtsov Institute of Ecology and EvolutionOlga Filatova - University of Southern DenmarkNeil R. Loneragan - Murdoch UniversityJoshua N. Smith - Murdoch University
- Marine ecology. Progress series (Halstenbek), Vol.726, pp.161-179
- Inter-Research
- 19
- SGPA/DHVS/9375/19 / Post-graduate International Scholarship of Murdoch University, Perth, Western Australia
- 991013372616702368
- Faculty of Science and Engineering
- English
- Journal article