August 21, 2026 — The Hawaiian archipelago is teeming with marine life, and winter brings some of the most exciting activity of the year. It’s a season when many whale and seabird species travel to the islands. Migratory baleen whales such as humpback and minke whales are only found in Hawai‘i in the winter, when they seek warmer waters to breed. Others—including various types of dolphins—rely on this marine ecosystem year-round, but scientists have yet to uncover the details of their wintertime habits.

To close that gap, the Pacific Islands Fisheries Science Center launched a survey in late January 2026. Scientists spent 2 months monitoring these species around the main Hawaiian islands aboard the NOAA Ship Oscar Elton Sette. The mission, called the Winter Hawaiian Islands Cetacean and Ecosystem Assessment Survey, is only the second of its kind.

Six years after the first winter survey, researchers returned to better understand where, when, and how many whales and dolphins use this habitat. The data from these surveys feed into stock assessments, helping us track the status of these species and make informed conservation decisions. This work is especially important for high-priority species like false killer whales, including an endangered population that lives around the main Hawaiian islands.

Winter conditions at sea can be rough, with higher swells and lots of white caps. This makes animals harder to see. But NOAA scientists are experienced with scientific methods that rise to the challenge. During the survey, eagle-eyed visual observers spied more than 200 groups of whales and dolphins, even in difficult conditions. They documented humpback mothers with their calves, bottlenose dolphins riding the ship’s bow, and pantropical spotted dolphins leaping high into the air. Cutting-edge passive acoustic technology helped detect other whales and dolphins that could be heard but not seen.

In these photos, take a look behind the scenes of the survey and find out which species spend their winters in Hawaiʻi.

Read the full article at NOAA Fisheries