Sea lions are consuming more salmon in the Columbia River, according to a new research on fish survival.

NOAA (National Oceanic and Atmospheric Administration) Fisheries preliminary research reveals a steady increase in fish mortality over a five-year period may be attributed to seals and sea lions.

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Michelle Rub, a researcher with the Northwest Fisheries Science Center, says the survival of spring Chinook salmon dropped from 90 percent in 2010 to 55 percent in 2014.

On the other hand, sea lions increased in numbers from an average of 80 in 2010 to 616 today.

"We have some pretty alarming survival estimates--particularly in the last couple of years," Rub said. "It's probably not a coincidence that as mortality is increasing, these sea lion numbers have just exploded."

The research also revealed fewer salmon returning to the river survive during the months of March and April when sea lion numbers are at their peak.

The disturbing reality of the research is that sea lion predation is theoretically killing about 22,500 to 57,000 Columbia River salmon.

Oregon Department of Fish and Wildlife (ODFW) is planning to test sea lion scat this spring to get a better idea of how much salmon sea lions are eating in the lower river.

Rub said she hopes to work with agencies that track tagged sea lions to see if salmon losses can be more directly tied to known sea lion locations.

TagsSea Lions, Columbia salmon, salmon, Chinook salmon