Ship-Whale Collisions Hint at Shift in Feeding

Over about eight weeks, three ships pulled into Northwest ports with a fin whale draped over the bulbous bow, a fuel-conserving device projecting into the ship’s path just below the waterline.

The first dead fin whale -- it is the world’s second-largest creature -- arrived at Seattle on the bow of the container ship Tokyo Express on Aug. 9. The second came into Portland, Ore., on the auto-transport vessel Ruby Ray on Sept. 2. The third reached a Cherry Point refinery on the bow of an oil tanker Oct. 2.

It’s happened before, but not in such quick succession.

“To have three come in so close together is something we’ve not seen before,” said Brent Norberg, marine-mammal coordinator for the National Marine Fisheries Service here.

It’s not clear why, although scientists speculate that the whales may have changed feeding patterns -- moving into traffic lanes in search of prey. It appears that “the food they’re grazing on happens to be on a freeway,” Norberg said.

Ship-whale collisions and other encounters -- net entanglements and propeller hits -- have been an increasing factor in whale deaths off the nation’s coast for some years, raising concerns among biologists. Ships are getting bigger and faster, while populations of the now-protected whales are increasing.

In the recent cases, tests indicate two of the whales were alive when they were struck. Damage to the Portland carcass suggests that it was already dead.

The carcasses, which ranged from 35 to 60 feet long, apparently were tucked up against the vessels by the bulbous bows. The odd-shaped projection has greatly increased fuel efficiency through “wave-making resistance reduction technology” developed in the early 1960s.

A bulbous bow would prevent a struck animal simply rolling off to the side, Norberg said. There is no research on whether bulbous-bow technology could be a factor in whale deaths, he added. . The percentage of bulbous-bow ships involved in collisions with whales is not known.

Crews “are as surprised as anyone when they pull in and the animal is there,” he said. The ships weigh thousands of tons: “That’s a massive object moving through the water;” striking a whale would be “kind of like hitting a noodle with your car.”

The remains of the two whales that probably were alive when struck were quite fresh when they reached port, Norberg said, which suggests that the strikes occurred as the vessels neared their journey’s end.

That reduces the chance that a whale strike would be noticed, he said. When ships near port, they are busy taking on pilots to navigate inland waters, slowing to enter the Strait of Juan de Fuca and making other routine changes in operational strategy.

Also, “crew size is going down as vessel speed and size are going up,” noted activist Fred Felleman of Ocean Advocates. “And even if somebody did see a whale, it’s not like a big ship can turn on a dime.”

Unlike toothed whales, baleen whales such as fin whales do not echo-locate -- a method of detecting objects and food by creating a series of clicks and interpreting the reflected sound. Even so, scientists believe that they have very sensitive hearing. And today’s bigger, faster ships generate “significant amounts of noise,” said whale expert John Calambokidis of Cascadia Research in Olympia.

Still, with few natural enemies, whales may not consider an approaching vessel a threat.

“These animals evolved over millions of years,” Calambokidis said. “The arrival of huge ships that travel 20 or more knots is a very recent development -- recent as in the last 100 years. It’s nothing they’re equipped or have evolved to recognize as a threat.”