Catalogs of Whale Tails Prove Revealing

March 7 -- Some people can never forget a face … and some scientists can never forget a tail.

Judy Allen, for example, has studied pages and pages of individual whale tail images for more than 20 years.

"Sometimes a tail is quite striking. It can be a black marking or a serrated edge," says Allen, who is associate director of Allied Whale, a marine mammal research group based at College of the Atlantic in Bar Harbor, Maine. "Look around your town and you can recognize people by their faces. It's a similar type of recognition."

Just as law enforcement agencies keep data bases of human fingerprints, scientists have maintained deep databases of whale tail images. And while police use fingerprints to track criminals, scientists have analyzed their databases to learn key elements of whale behavior. The whale catalogs may also eventually lead to one long-sought bit of knowledge: exactly how long particular whales can live.

20 Years of Whale Tails

Sean Todd, director of Allied Whale, says the program has amassed more than 10,000 images of about 6,000 individual whales in the North Atlantic since the late 1970s. Recent studies estimate a total of between 10,000 and 11,000 humpback whales now inhabit the ocean.

Less comprehensive are the catalogs of humpback whales in the Antarctic where long, severe winters and very rough waters can make tracking whales treacherous work. Researchers with Allied Whale have only recently begun gathering images of whale tails in Antarctic waters. In fact, Todd and Allen just returned from a cruise in the Antarctic sponsored by the Abercrombie and Kent Global Foundation where they collected 10 new images of humpback whale tails. The Antarctic whale tail catalog now lists about 1,000 individuals.

Todd explains it takes about a three-person crew to capture a whale tail image. One person steers the boat, another takes notes while a third snaps photographs.

"We follow the animal until it goes into a terminal dive," says Todd, explaining that a whale conducts a terminal dive after its lungs have filled with oxygen and it's ready to return to the deep. To make the deep dive, it raises its tail high in the air and plunges straight down.