Humpback Whales’ Migration Timing at Risk Amid Climate Change
A groundbreaking study led by McGill University researchers reveals that humpback whales in the southeastern Pacific rely on a combination of real-time environmental cues and long-term memory of Antarctic feeding grounds to determine their annual migration. However, with climate change accelerating, this adaptive strategy may become less effective as ocean conditions rapidly shift.
How Humpback Whales Time Their 10,000-Kilometer Migration
The research team analyzed eight years of satellite tracking data (2009–2016) from 42 humpback whales tagged off the coasts of Costa Rica, Panama, and Ecuador. Their objective was to understand the triggers behind the whales’ southward migration to Antarctica’s Southern Ocean.
The findings indicate that humpback whales integrate local environmental changes—such as sea temperature and food availability—with their memory of past oceanic conditions in their Antarctic feeding grounds. This enables them to synchronize their migration with the seasonal krill bloom, ensuring they arrive at the optimal time for feeding.
“They appear to recognize that changes in their immediate environment are connected to conditions thousands of kilometers away,” said lead author Professor Virginie Millien, a biologist at McGill University. “This ability allows them to fine-tune their migration and maximize feeding opportunities.”
Climate Change Disrupting Whale Migration Patterns
For thousands of years, this migration strategy has been reliable. However, with rising global temperatures and shifting oceanic conditions, it is now under threat. Warming waters and changing sea ice patterns are delaying the krill bloom, disrupting the whales’ feeding cycle.
“We don’t know how long they’ll be able to keep up,” Millien warned. “Every year since 2016 has been the warmest on record, and climate change is accelerating. At some point, their memory-based navigation may no longer be effective.”
Differences in Migration Between Males and Females
The study also uncovered gender-based differences in migration patterns. Males tend to travel faster and take more direct routes, whereas females—especially those with calves—follow longer coastal routes, likely to avoid predators and allow their young to rest.
Conservation Efforts: Protecting Whale Migration Corridors
With increasing ship traffic along coastal migration routes, humpback whales face heightened risks from vessel collisions and habitat disruption. The researchers emphasize the urgent need for conservation measures to protect key migration corridors and feeding grounds.
Co-author Hector Guzman of the Smithsonian Tropical Research Institute has been advocating for policy changes, including reduced vessel speeds in critical whale habitats.
“This study provides essential data to support conservation efforts,” said Guzman. “Safeguarding humpback whales also helps maintain the delicate balance of marine ecosystems.”
Key Takeaways
- Humpback whales use memory and environmental cues to time their migration.
- Climate change is disrupting krill availability, affecting whale feeding cycles.
- Males migrate faster, while females take longer, safer routes.
- Conservation measures are needed to protect whale migration pathways.
More Information:
Virginie Millien et al., Migratory Behaviour of Humpback Whales in the Southeastern Pacific Under Climate Change, Scientific Reports (2025). DOI: 10.1038/s41598-025-87489-4
Provided by: McGill University