Every winter, humpback whales (Megaptera novaeangliae) undertake massive migrations from feeding grounds in the Gulf of Alaska and the Bering Sea to tropical and subtropical breeding areas. The Revillagigedo Archipelago serves as one of the most vital of these tropical reproductive sites. The whales utilizing this area belong to the “Oceanic Population Unit,” a distinct group known for high site fidelity. To support the study of this critical habitat, Lokahi Ocean Science is teaming up with the PRIMMA Lab at UABCS  to conduct a month-long expedition to Socorro Island, using our vessel as our base and conducting operations with our dinghy along the island’s coastline.

The primary drive for this research is to gather data on the distribution, movements, body condition, and genetics of these whales.  The findings will help us to understand how climate change is restructuring migration patterns and population dynamics. 

Methods

1. Photo-Identification: Identify individuals by taking photographs of their dorsal and caudal fins. Using HappyWhale, we can see where this individual has been sighted in the past.

2. Aerial Assessments: Deploy a Mavic 3 drone to estimate the body condition.

3. Collect Tissue Biopsies: Obtain skin and blubber samples for genetic, stable isotope, and contaminant testing.

4. Record Acoustic Data: Submerge an omnidirectional hydrophone during encounters to capture recordings of humpback whale songs.

Objectives

• Clarify Conservation Status: Provide an updated, data-backed assessment of the “Oceanic Population Unit” of humpback whales to help evaluate their official conservation status.

• Map Migratory Corridors: Use the gathered genetic and photographic data to better understand the specific “herds” and the migratory connections between the Revillagigedo breeding grounds and northern feeding zones.

• Determine the health of each herd by analyzing their body condition to see if we can find any relationships between heat waves and animal health.

• Strengthen Long-Term Data: Directly contribute to the PRIMMA-UABCS long-term datasets to build a deeper understanding of humpback whale populations across the Mexican Pacific.