GRAYS HARBOR, Wash. — Biologists with the Cascadia Research Collective, who were out on Washington waters to survey gray whales and humpback whales, were greeted with an unexpected sight.   

Two blue whales were spotted on July 24 in shallow water about 17 miles off the coast of Grays Harbor, feeding off a swarm of krill.

Seeing a blue whale this far north is incredibly rare. John Calambokidis, one of the biologists who spotted the whales, said there have been less than five sightings of them near Washington in the last 50 years. 

The most recent documented sightings were in 2011 when six blue whales were seen feeding off the Washington coast, according to Cascadia Research.

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Blue whales, the largest animals on the planet, are usually found in waters near California. Calambokidis said they can sometimes be found as far south as Central America and as far north as Alaska.

Calambokidis said the whales follow the krill, which brought them to the area.

According to Calambokidis, recent Cascadia surveys indicate that several blue whales have been spotted off the coast of Oregon.

It's unclear if the blue whales' shift north is permanent.

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