Researchers to assess humpback health

SEATTLE – Researchers are heading out into the North Pacific this weekend on a four-month mission to learn more about humpback whales, acrobatic crowd-pleasers up to 50 feet long whose eerie, plaintive songs have been recorded for CDs.

The voyage of the federal research ship McArthur II marks the big-bang kickoff of a three-year, $3 million multinational effort to assess the region’s humpback population, which was decimated by more than a century of commercial whaling.

“This is the largest whale project that has ever been attempted – the most people and the biggest ocean,” said Jay Barlow, chief scientist on the research vessel McArthur II, part of the National Oceanic and Atmospheric Administration fleet.

The undertaking is called SPLASH, for Structure of Populations, Level of Abundance and Status of Humpbacks.

The count, bankrolled by NOAA, will gather input from scientists and volunteers all along the Pacific Rim – Japan, Russia, Mexico, Canada, the Philippines, Costa Rica, Panama, Nicaragua, Guatemala and along the U.S. coast.

Humpbacks, which feed in northern waters over the summer and then head south in winter to breed off Hawaii, Japan, Mexico and Central America, are believed to make the longest migration of any mammal – as much as 5,000 miles one way, said longtime whale researcher John Calambokidis of Cascadia Research in Olympia, who will be conducting small-boat West Coast counts.

That makes international cooperation essential, said the researchers, who held a news conference at NOAA’s Lake Union facility along with Ed Bowlby, research coordinator at the agency’s Olympic Coast National Marine Sanctuary.

Up to now, “we knew about each other’s research,” but there had been little formal collaboration, Calambokidis said.

Scientists believe the North Pacific population had dropped to about 2,000 – probably less than 10 percent of pre-whaling levels – when California whaling stations were shut down in 1966. At that time, the huge mammals were hunted for their oil and for use as fertilizer and dog food.

They’re now believed to number more than 10,000, Barlow said, and the population appears to be growing 6 percent to 8 percent a year.

Like much marine life, humpbacks remain a mystery to landlocked humans.

“We see so little of the humpback whale. … All its life is conducted underwater,” Barlow said. And while 10,000 may sound like a lot of animals, spread over the vast Pacific “they can be very difficult to find.”

Also, unlike gray whales, which migrate en masse, humpbacks tend to travel alone or in pairs, though groups of 10 to 15 may gather to feed.

In addition to a more accurate population count, researchers hope to learn more about the whales’ migration patterns – little is known about where they spend summers – and whether the population is growing and how fast.

Another issue is the impact of human activity. Toxin levels are a concern, and the air-breathing whales sometimes get tangled in fishing nets and drown.

The McArthur II will travel north to explore feeding grounds along the British Columbia and Alaska coasts, west to Russia’s Kamchatka Peninsula and then east to the south Bering Sea before heading home to NOAA’s Lake Union dock north of downtown.

The humpbacks that feed in these areas winter in Hawaii and Japan, while those that breed off Mexico and Central America tend to feed off the U.S. coast. They generally stay along the continental shelf – about 50 miles offshore – though a 30-foot humpback was spotted in Puget Sound waters off Tacoma earlier this month.

The 224-foot McArthur II will zigzag along its route, traveling about 100 miles a day, Barlow said.

When whales are spotted, researchers will approach on inflatable vessels to photograph their tail flukes – the undersides, visible when they dive, are as individual as fingerprints.

The vessel also will tow an array of hydrophones to listen for whales below the surface. The singing tends to occur only at the winter breeding grounds, Barlow said, but humpbacks do make sounds while feeding.

Tissue samples less than an inch thick will be taken by crossbow so researchers can collect genetic data and learn about toxin levels.

Humpbacks are baleen whales, which feed on tiny marine animals by straining water through bony plates, called baleen, in their mouths. Toxins tend to be more of a concern higher up the food chain.