Cameras on the backs of baby humpback whales have captured a rare glimpse of moms nursing their calves.

In addition to a camera, the suction-cup tags also carry an acoustic recorder, depth sensor and accelerometer, which together, collect data on the behavior, movement and breathing patterns of the whales. Researchers also deployed drones to simultaneously watch the graceful creatures from above and observe their size and body condition.

The team, which includes scientists from the University of Hawaii at Mānoa Marine Mammal Research Program, the Stanford University Hopkins Marine Station and the University of California, Santa Cruz, is interested in finding out how often and for how long the calves nurse — a behavior that's tricky for researchers to observe from the surface.

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"We can actually see what these animals are seeing and encountering and experiencing themselves," Lars Bejder, the director of the Marine Mammal Research Program, said in a statement. "Itʻs quite unique and rare footage that we're obtaining, which is allowing us to quantify these nursing and suckling bouts that are so important."

About 100,000 humpback whales (Megaptera novaeangliae) visit the crystal clear waters off the coast of Maui, Hawaii, between January and March each year. The whales spend this time exclusively breeding, and they rely solely on energy stored from their previous summer feeding season in Alaska.

The data collected in this study will provide important insights into the nutritional needs of humpback mothers and calves while they're hanging out in their Maui breeding grounds.

Humpback whale research in Hawaii is a largely collaborative effort. Tag deployment and retrieval were made possible with help from local whale conservation and ecotourism groups.

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