Northwest orca mothers, babies starving to death

FILE - In this July 31, 2015, file photo, an orca whale breaches in view of Mount Baker, some 60 miles distant, in the Salish Sea in the San Juan Islands, Wash. Two females and a 10-month old calf are believed gone. (AP Photo/Elaine Thompson, File)

Researchers who track the endangered population of orcas that frequent Washington state waters believe four whales are believed dead or missing since summer.

The Center for Whale Research said Friday that only 80 animals were accounted for during its July 1 census. Two females and a 10-month-old calf are missing.

Center senior scientist Ken Balcomb says the orcas, particularly mothers and babies, are struggling because they don't have enough food, a primary factor in their decline.

>> Photos of NW orcas that died amid food supply concerns 

He and others say breaching four dams on the Lower Snake River is the best opportunity to save the orcas and restore runs of salmon that the killer whales eat.

The whales have a strong preference for chinook salmon, which are typically larger and fatter fish, but those runs have been declining.

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