A new federal law aims to increase salmon stocks in the Pacific Northwest by allowing states and tribal governments to kill a limited number of sea lions.

The Endangered Salmon Predation Prevention Act passed both houses of Congress and was signed by President Trump on December 18. The law amends the 1972 Marine Mammal Protection Act by allowing the killing of up to 900 sea lions per year in parts of the Columbia River and its tributaries by certain entitites.

The states of Washington, Oregon and Idaho, as well as six tribal groups including the Nez Perce Tribe and the Confederated Tribes of the Umatilla Indian Reservation, could be permitted to kill up to 100 sea lions each per year under the new measure, as long as their cumulative take is within “ten percent of the annual potential biological removal level,” a summary of the bill states.

The potential biological removal level is defined by law as the maximum number of animals that can be removed from a marine mammal population while still allowing the population to maintain optimum sustainability, a NOAA fact sheet states.

The bill’s passage follows a slate of illegal sea lion killings in the Puget Sound region in recent months that have worried wildlife officials.

According to Michael Milstein of NOAA, 12 sea lions have been found shot over the last three months in Kitsap and King Counties. An investigation is ongoing and no arrests have been made yet, Milstein said.

Anglers, commercial fishermen, tribal groups and others have complained about the 1972 Act, which forbids the taking of marine mammals except in very specific circumstances.

“We’re watching our salmon fisheries go down, and their taking the orcas with it,” Ron Garner of the Puget Sound Anglers Club said during an interview last month. “It’s time they get it fixed,” he said, referring to the law.

The Humane Society of the United States has expressed opposition to the new law, Milstein said.

The legislation was proposed in the Senate by Jim Risch, R-Idaho, and Maria Cantwell, D-Wash. Gov. Jay Inslee has also expressed support for the bill.

“Wild salmon are central to the culture, economy, and tribal treaty rights of the Pacific Northwest,” Cantwell said in a statement. “This science-based, bipartisan bill enhances existing tools that state and tribal wildlife managers need to address salmon predation, protects the health of sea lion stocks, and ensures that we are managing wildlife based on the best science available.”

Gabe Stutman is a reporter with the Kitsap News Group. Follow him on Twitter @kitsapgabe.