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Whales appear to be returning to Island waters after area population was wiped out in 1967

Katherine Dedyna, Times Colonist
Published: Thursday, October 18, 2007

It began as a low, inquisitive bellow, then morphed into quasi-barks, growls and echoing calls. For the first time in 25 years, the "true song" of the humpback whale has serenaded spellbound whale researchers in West Coast waters.

The haunting 25-minute "rhapsody" was caught on tape on Oct. 11, the first time that has happened since OrcaLab's hydrophone network was installed in the early 1980s around its northern Vancouver Island location.

"We've been listening all this time," says whale researcher Paul Spong an OrcaLab director who was mesmerized by the sound. The call of the humpback, almost certainly a male, has been posted on the website of the whale research station at www.orcalab.org.

OrcaLab, on Hanson Island at Blackney Pass, has six hydrophones covering 50 square kilometres listening for orcas. Other than "a few tentative sounds" in recent years and a 10-minute session on Sept. 11, there has been no humpback singing in that territory.

Last week's long, impressive and expressive song meant a lot to Spong. "We were just very moved by it."

The unique series of whale phrases and repetitions occurred in Blackfish Sound at the southern end of Queen Charlotte Strait. Its length and complexity signals that the humpbacks may finally be feeling at home in West Coast waters again. "It's a safe place for them to come -- it's also a place where they can find food."

Humpbacks feed on herring and pilchard, among other small fish.

Spong doesn't know how many humpbacks might be cruising B.C.'s coast, but notes that Port McNeill biologist Jackie Hildlreing has a catalogue of 77 humpbacks observed in West Coast waters. They're common enough to be seen as integral to the whale-watching business.

The repetitive phrases of humpback sound compare to verses in songs, explains Spong, a psychologist. Orca calls are commonly heard by OrcaLab but are not repetitive in the same way as the humpback song.

"In general, the songs are thought to have a role in mating," says Spong, perhaps as a form of male display to impress females.

Most of this big humpback song appears to be in the voice of one whale, almost certainly a male, although toward the end there's an indication another humpback may have joined in.

"It was just amazing," said Spong. "It was such a thrill for us to hear the sound."

Humpbacks are mid-sized whales, reaching 10 metres and 30 tonnes.

Spong points out that the population is threatened with an annual whale hunt by Japan. The Japanese are planning to kill 50 humpbacks in southern waters "in the guise of science," Spong said. Many environmental groups also object to the annual whale kill, but Japan argues the program is needed to gauge whale populations and study their breeding and feeding habits.

Forty years ago, the Coal Harbour whaling station near Port Hardy was the last whaling station in North America.

"In 1967, faced with a shortage of whales in nearby Pacific waters, the whalers travelled around the top of Vancouver Island into Queen Charlotte Strait, Blackfish Sound and Knight Inlet," reports OrcaLab. "There, they found a tiny remnant population of 13 humpbacks. Every last one of them was killed."

There was complete humpback silence until 1982. The numbers began to recover after a lone humpback was seen swimming east past Alert Bay toward Johnstone Strait.

"Possibly, this explorer brought news to other humpbacks, because in the years that followed, humpbacks gradually began to return to these waters," OrcaLab reports.

An inter-species vocalization between a humpback and some orcas was picked up by hydrophone last year in Robson Bight but didn't last long.

OrcaLab is convinced that humpbacks are "truly at home here once more" based on greater numbers combined with more vocalization. Where they swim the rest of their lives is not known, but Hawaiian waters are likely.




Source - Times Colonist