December 30, 2019 — Two studies and a state report released this month build on the efforts to understand what’s impacting the region’s endangered Southern Resident orca whales and what steps could be taken to help save them.
Researchers and wildlife managers have for years suggested that the Southern Resident orcas, which spend several months of the year in the Salish Sea and coastal waters of Washington, are struggling to find large, nutrient-rich chinook salmon to eat.
Studies recently published in the Proceedings of the National Academy of Sciences suggest the Southern Resident orcas are competing with other fish-eating orca populations of the North Pacific Ocean and that orca calves born to families without grandmothers have a lesser chance of finding chinook to eat and surviving to adulthood.
Meanwhile, a draft state report released Dec. 20 concludes it’s not clear whether a move long called for by environment and wildlife groups – to remove dams on the lower Snake River – would significantly boost the number of fish available to the region’s orcas.
Removing four dams on the lower Snake River in southeast Washington, where it curves from the Idaho border toward the Oregon border, could improve conditions in the river system for salmon, according to the report.