Crater Lake managers introduced an invasive crayfish in 1915, and now it may wipe out a unique newt

Posted

The federal government announced this week that it is considering listing an Oregon newt that lives only at Crater Lake National Park as threatened or endangered because an invasive predator has exploded in numbers and is on the brink of exterminating the newt.

The demise of the Crater Lake newt, also known as the Mazama newt, has rapidly accelerated in the past 15 years or so — brought on by climate change’s warming temperatures, which favor the newt’s predator, the signal crayfish, according to a national conservation nonprofit that is petitioning the U.S. Fish and Wildlife Service to protect the newt as an endangered species.

The crayfish occupied about 50% of the shoreline in 2008, but that ballooned to 80% in 2020, according to the National Park Service. The nonprofit that is pushing for the newt’s protection, — the Center for Biological Diversity — says that number has now reached about 95%. And anywhere the crayfish live, the newts aren’t to be found.

The nonprofit estimates that the crayfish could occupy 100% of the shoreline in as little as two years.

“Without endangered species protections this cute little newt will soon blink out of existence,” said Chelsea Stewart-Fusek, an attorney for the nonprofit, in a news release. “We need funding right now to remove signal crayfish from Crater Lake so these newts aren’t wiped out. Otherwise, this incredible lake will be changed forever.”

The Center for Biological Diversity also says as the crayfish multiply, the crystal clear clarity of the lake’s water could worsen as more algae bloom. That’s because the crayfish also prey on algae-eating plankton in the lake, the center said.



This chain of problems began well over a century ago, in the late 1800s, when enthusiasts began stocking fish in the lake in hopes of attracting visitors, elevating public interest and gaining federal protection, according to the National Park Service. The plan worked, with the federal government designating the lake a national park in 1902.

The Center for Biological Diversity says park managers introduced the non-native crayfish in 1915 as a food source for the fish. And everything remained relatively stable until temperatures began to rise. The crayfish have now become an existential threat to the endemic newt.

The newts are a subspecies of the rough-skinned newt that lives across the Pacific Northwest. The Crater Lake newt has been found only in the waters and along the shoreline of the lake. Unlike the more common rough-skinned newt, which contains a potent neurotoxin to deter predators, the Crater Lake newt is relatively defenseless, scientists say.

— Aimee Green covers breaking news and the justice system. Reach her at 503-294-5119, agreen@oregonian.com or @o_aimee.

Our journalism needs your support. Subscribe today to OregonLive.com.

©2024 Advance Local Media LLC. Visit oregonlive.com. Distributed by Tribune Content Agency, LLC.