Environment: Calling all Humpbacks

A cooperative research project took a comprehensive look at whales.

Humpback whales continue to flock to the Islands this winter season to mate and give birth in our warm waters. The big news? They’ve just been pursued like never before across the North Pacific, in a massive cooperative effort involving an estimated 300 researchers from 50 organizations and 10 areas—including the United States, Canada, Mexico, Central America, Russia, Japan and the Philippines.

These scientists recently concluded a three-year project known as the Structure of Populations, Level of Abundance and Status of Humpbacks (SPLASH), the largest research survey ever conducted on any type of whales. Some of the questions the scientists hope to answer are: How many North Pacific humpback whales exist? Is the North Pacific humpback species one big population, or a collection of smaller groups that migrate to the same regions year after year? What kind of negative impacts are humans having on the whale?

ID, please: Researchers took photos of humpback whales to identify each individual. photo: Doug Perrine/courtesy of the Hawaiian Islands Humpback Whale NMS

The SPLASH project was unique in that each region used the same methods for collecting data. For instance, researchers took approximately 10,000 photographs of the fluke, or tail pattern, of humpback whales to identify each individual and monitor its movements over the three-year period.

Another method involved collecting a tiny tissue sample—the size of a pencil eraser—by shooting a dart from a crossbow. (Not to worry, most of the whales didn’t even react.) “Since you can’t catch one and take its blood or measure it, the biopsy sample allows us to look at different things: genetics, sex, toxin levels, even what it’s eating,” says David Mattila, co-chair of the SPLASH steering committee and the science and rescue coordinator for the Hawaiian Islands Humpback Whale National Marine Sanctuary.

SPLASH also sent expeditions to places that weren’t previously surveyed. “These included regions such as Far East Russia, the Bering Sea and the offshore waters of Alaska—where no one had been since whaling was in place decades ago,” says Mattila.

Although the project’s data analysis won’t be completed until the fall, preliminary findings show that there are, indeed, substructure populations. That is, separate populations that migrate to the same regions every year, such as California whales that migrate down to Central America in the winter. The biggest subpopulation seems to be the one that comes to Hawai‘i from Alaska. While exact numbers aren’t in yet, the group is not only healthy, but is also growing at a considerable rate. A guesstimate based on an annual population increase of 6 percent to 7 percent puts the number of whales coming to Hawai‘i every year at around 10,000.

There are exceptions, though. One humpback traveled all the way from Russia to Hawai‘i, and another was found in Hawai‘i one winter, and in the Philippines the next. What a couple of nomads!