Humpbacks make a SPLASH in the N. Pacific

May 23, 2008

By Alana Phillips

Humpback whales were historically abundant in the Pacific Ocean, but extensive whaling almost resulted in their extinction. By the mid-1960s, it’s estimated that fewer than 1,500 humpback whales remained in the North Pacific. Humpback whales completely disappeared from many regions around the coast of British Columbia for decades.

From 2004-2006, an international multi-agency research effort known as SPLASH (Structure of Populations, Levels of Abundance, and Status of Humpbacks) has been working to determine the number of humpback whales in the North Pacific Ocean. This study is one of the largest international collaborative studies of any whale population ever conducted, involving over 50 research groups in 10 countries around the Pacific Rim.

Whale biologists surveyed the whales’ winter breeding areas and their summer feeding areas, and took photographs of the whales’ tail flukes, which are individually identifiable by their black and white colour patterns and presence of scars, nicks and scratches. By matching photos from different areas, the biologists were able to track individual animals across the Pacific Ocean, and determine where the whales travel throughout the year. For example, they found that most of the humpback whales that breed in Hawaii travel to the Gulf of Alaska and the Bering Sea in the summer feeding months, while whales that breed in Mexico tend to feed off the coasts of California and Oregon.

In the SPLASH Final Report released this week, biologists showed that by applying statistical models to the counts of humpback whales that were photographed, they estimated that the current number of humpback whales is between 18,000 to 20,000 whales, a much higher number than was previously thought. Over the last few months, we’ve had regular reports of humpback whales in the Strait of Georgia, and recently had our first report of a humpback whale in Howe Sound , north of Vancouver – the first confirmed sighting of this species in Howe Sound in 100 years!

Although that’s great news for the whales, they still face many threats in our area. Because they feed on schooling fish such as herring, humpback whales are vulnerable to entanglement in fishing gear, and are likely ingesting contaminants from human sources that make their way up the ocean food web. As humpback whales become more numerous in our waters, they’ll encounter high volumes of vessel traffic ranging from pleasure craft to tug boats, ferries, cruise ships and cargo ships, all of which increase the risk of collisions, disturbance and underwater noise.

You can help! If you see a humpback whale, please follow the Be Whale Wise guidelines. View the whales from a distance and allow them space to perform their natural behaviours. If you see a whale that’s entangled in fishing gear, please call the DFO Incident Reporting Line at 1-800-465-4336. And finally, be sure to send us your sightings – every report we receive helps to protect humpback whales and other cetaceans along our coast.

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Humpbacks make a SPLASH in the N. Pacific

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