Whale stranding a mystery

  • Fri Aug 24th, 2007 3:00pm
  • News

It’s hard to say what caused the stranding of the young humpback at North Beach on August 20, says BC whale researcher, Dr. John Ford. “Since it was a calf, it could have been a navigational error,” said Dr. Ford. “When there is a live stranding of a baleen whale, usually its health is compromised and it can be a last ditch effort to not drown.” When he learned that an adult humpback was lingering offshore throughout the calf’s ordeal, Dr. Ford said, “There probably isn’t anything wrong with that calf, it is weaning time…the fact that it hasn’t been back is a good sign.” The calf was found beached in shallow water about a kilometre from Tow Hill on a falling tide. People kept it alive for almost 12 hours by covering it with blankets and spraying seawater on it throughout the long day. “Usually stranded whales don’t get off the beach…achieving that is uncommon,” Ford said, “Its a great thing to see people’s efforts to rescue this calf and it looks successful since it hasn’t been found back on the beach.” Kathy Heise, a whale research associate at Vancouver Aquarium agreed with Dr. Ford that the calf could have made a mistake when it came into shallow waters. She said there could be any number of reasons why the young whale beached itself. “It is unknown why, when no one was there to see…it could have been chased by killer whales,” she said. Dr. Ford also had a report that the calf was briefly beached near the Agate Beach campground in the evening of August 29. “Usually when animals strand repeatedly they eventually die,” he said. Large scratches on the calf’s back were noticed by Ford in photos sent to him. These will help identify the calf if it’s seen again. “Also, the most identifying feature of the calf is distinct markings on its dorsal fin,” he said. “Unfortunately, Its tricky to see injuries, orcas can internally bruise a humpback, causing it to die later…we just don’t know yet,” said Ms Heise. “The internal organs can be crushed when a humpback is stranded, there could have been unnoticed damage to the calf .” Humpback calves are born in the winter in warmer waters of Hawaii and Mexico. The calves nurse for 10 to 12 months and then leave their mothers. Humpbacks have one of the longest migrations of any mammal and spend spring, summer, and fall in the waters of Haida Gwaii where they feed on krill, herring and sand lance. In the Pacific, humpbacks are listed as Threatened by the Committee on Endangered Wildlife in Canada. However, they have had a significant increase in numbers since the early 1990s. This year, researchers counted almost 200 humpbacks in the waters of Haida Gwaii.