Whale Entanglements in Fishing Gear Surge Off U.S. West Coast During Marine Heatwaves

Each spring, humpback whales migrate to the coast of California and Oregon to feed on dense schools of anchovies, sardines, and krill. This feeding behavior is supported by a process known as coastal upwelling, which brings cool, nutrient-rich water from the deep ocean to the surface. The California Current is recognized as one of the most productive marine ecosystems due to this seasonal phenomenon, which is crucial for the whales' feeding habits. Recent research indicates that the risk of humpback whales becoming entangled in fishing gear is significantly influenced by the availability of cool-water habitat. During years when this habitat is less available, the likelihood of entanglement increases. This finding was presented by Jarrod Santora of the National Oceanic and Atmospheric Administration and colleagues in a study published in PLOS Climate. The study highlights the correlation between the size of the cool-water habitat and the risk of entanglement, suggesting that environmental conditions play a critical role in the safety of these whales. The surge in whale entanglements off the U.S. West Coast has been observed during marine heatwaves, which can disrupt the availability of the cool-water habitats essential for the whales' feeding. As these heatwaves become more frequent, the implications for whale populations and their interactions with fishing gear are becoming increasingly concerning. The research underscores the need for monitoring and management strategies to protect humpback whales from entanglement risks associated with changing ocean conditions.