Tropical dolphins spotted in Puget Sound – Third warm-water species in seven months

By Judith Lavoie, Times Colonist
24 June 2011 Two dolphins that would be more at home frolicking in the warm bays of southern California or Mexico are cruising the chilly waters of Puget Sound and biologists are baffled by an apparent trend for tropical species to head north. Reports of strange whistles started coming in to the Orca Network in late May followed by sightings of unidentified cetaceans reported to the Cascadia Research Collective, an Olympia marine mammal research group. On June 4, the strangers were confirmed by Cascadia biologist Annie Douglas as long-beaked common dolphins, a species that has never previously been seen in Puget Sound. “The first photos were of a juvenile animal and the one we are seeing now is an older animal, maybe subadult,” she said. Victoria zoologist Anna Hall, who also skippers a boat for Prince of Whales whalewatching, said the only previously recorded sighting in local waters was in April 1953 when a longbeaked common dolphin stranded itself off Victoria. “It’s really, really unusual,” she said. […] The common dolphins are the third tropical species to turn up in Puget Sound or Juan de Fuca Strait within the last seven months. In January a bottlenose dolphin, a species that rarely goes north of central California, stranded and died near the Nisqually Delta in Puget Sound, after being seen in the area for at least a month prior to its death, and in December a Bryde’s whale died after being severely injured by a ship. Another Bryde’s whale stranded and died in southern Puget Sound in January 2010. Bryde’s whales usually prefer tropical or warm temperate waters. It is a mystery why tropical species are coming north, Douglas said. “It seems there is a significant change and it’s probably temperature related, but we don’t know much more than that,” she said. “Maybe in a year or two we will be able to say that this was the beginning of a change.” Howard Garrett of Orca Network said the appearance of warm-water species is “totally inexplicable,” especially as it is a La Nina year, meaning the water is colder than usual. […]

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