People near the small port town of Astoria, Oregon, were treated to a bizarre sight earlier this week: several humpback whales swimming in the Columbia River.
Oregon Public Broadcasting reported the whales were spotted near the Astoria-Megler Bridge, located 14 miles from where the river meets the Pacific Ocean.
"It’s really great to be able to see it, but you also wonder what's going on out in the ocean," said biologist Deborah Jacques, adding she’s never seen humpbacks so far upriver.
The Columbia River forms nearly the entire border between Oregon and Washington.
Bruce Mate, director of the Marine Mammal Institute at Oregon State University's Hatfield Marine Science Center, told Portland CBS affiliate KOIN 6 News that the whales were likely chasing anchovies and that El Niño conditions are driving them closer to shore in search for food.
"We have circumstances off shore that don’t favor whales very well this summer," Mate said. "It’s a very strong El Niño so the productivity is low and animals are seeking out resources where they can find them."
El Niño is characterized by unusually warm ocean temperatures in the Equatorial Pacific and can significantly impact weather and climate around the globe.
If El Niño events increase or get closer together, seeing humpbacks in the river could become more common, Mate told The Oregonian.
Humpback whales can be seen along the Oregon and Washington coasts during their migrations between northern waters and their breeding grounds near Hawaii. However, they are usually 5 to 15 miles offshore.
Vince Patton, a producer at Oregon Public Broadcasting, captured footage of the whales upriver after noticing a "feeding frenzy of pelicans diving into the water."
Watch the full video below.
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