UH research finds Hawaiian pilot whales eat 416 million squid a 12 months to energy deep dives : Maui Now

For the primary time, scientists have calculated an in depth “energetic budget” for Hawaiʻi’s short-finned pilot whales, revealing what it takes to energy their excessive, 800-meter (2,600-foot) dives for meals.

A brand new research led by the University of Hawaiʻi’s Hawaiʻi Institute of Marine Biology discovered a median grownup whale should eat 142 squid every day to outlive, scaling as much as 416 million squid yearly for the complete inhabitants of short-finned pilot whales. The knowledge, published within the Journal of Experimental Biology, supplies a benchmark for safeguarding the traditionally understudied marine mammals.

“Pilot whales are one of the only oceanic dolphins that regularly dive to extreme depths—up to 1,000 meters—to find prey,” mentioned William Gough, Marine Mammal Research Program (MMRP) postdoctoral researcher and lead writer of the research. “This deep-diving, high-risk foraging strategy requires a delicate balance between the energy they spend and the energy they acquire. Our study is the first step in quantifying that balance for this specific population.”

The deep waters surrounding the Hawaiian Islands are dwelling to a genetically distinct inhabitants of short-finned pilot whales. These extremely social, toothed whales should not migratory; they continue to be with their tight-knit, multi-generational households in a single area for all times. The inhabitants forages year-round the place they pursue their most popular prey: squid.

Using high-tech tags on eight pilot whales off Lānaʻi between 2021 and 2024, researchers measured motion, depth, sound and video to estimate vitality use throughout dives. They additionally analyzed the abdomen contents of a stranded whale and recorded the animals’ speedy “clicks” throughout hunts to find out their food plan and prey success price.

The researchers mentioned that understanding exactly how a lot vitality the animals require is important for understanding tips on how to successfully handle towards threats and guarantee their survival. 

“Deep-diving species like pilot whales are especially vulnerable to human-induced disturbances, such as noises from ships or changes in ocean temperature, which can disrupt foraging or increase their energetic costs,” Gough mentioned. “If they use more energy than they can find, they face an energy crisis that weakens their health, hurts their ability to fight off disease, and ultimately limits their ability to reproduce and recover the population.”

Despite this inherent vulnerability, the Hawaiian pilot whale inhabitants advantages from a steady and plentiful squid meals supply, which can higher equip them to deal with environmental disturbances than populations elsewhere.

Pilot whales are at the moment listed as “data-deficient” by the International Union for Conservation of Nature, regardless of having comparatively giant inhabitants sizes. This classification means scientists lack the data they require to precisely assess their threat of extinction. MMRP plans to use these scientific strategies to estimate the energetic expenditure of different cetacean species, from the harbor porpoise to the blue whale, with the aim of building a world benchmark for marine mammal conservation.

The report will be accessed at Journal of Experimental Biology.