Mazama newt eggs laid for first time in human care

Eggs represent 'huge milestone' in effort to save Crater Lake's Mazama newt

Two Mazama newts at the Oregon Zoo's conservation lab laid eggs last month - marking the first time this imperiled amphibian has produced eggs in human care. The newts arrived at the zoo last August, as part of an emergency effort with the National Park Service and the High Desert Museum to save them from extinction.

"This is a huge milestone," said Julia Low, who oversees the zoo's newt conservation efforts. "It tells us we're giving the newts what they need to thrive, and that they feel comfortable enough to breed. Every tiny egg gets us closer to saving them."

The two newts have laid a total of 52 eggs, each about the size of a mustard seed. Low isn't sure yet if any of the eggs will hatch, but some show promising signs of cell division and development.

"We check the eggs daily with a microscope," Low said. "Mazama newt eggs have never been documented in the wild, and since this is the first time they have laid eggs in human care, everything we're observing is new information."

Care staff don't know exactly what to expect during this inaugural Mazama newt breeding season, so they're using data from axolotl eggs to chart the newts' progress. Whether the eggs hatch or not, experts agree they represent a major step forward in the conservation effort.

"This is a very promising development," said David Hering, an aquatic ecologist at Crater Lake National Park. "It means we're one step closer to reintroducing newts to Crater Lake."

Historically, Mazama newts were the top aquatic predator in Crater Lake, but in recent years they've been threatened by invasive signal crayfish, which are taking over the lakeshore.

"If we don't act now, the Mazama newt could disappear," Hering said. "We need to keep a population of these newts safe in human care while we work on a long-term solution to the invasive crayfish problem, and that's where the Oregon Zoo comes in."

This is the first cohort of Mazama newts to live at the Oregon Zoo's conservation lab, but the zoo has a history of bringing native species back from the brink. For more than 25 years, the zoo has spearheaded conservation triumphs with California condors, native butterflies, northwestern pond turtles, northern leopard frogs and more.

The Mazama newt has been included in Oregon's revised State Wildlife Action Plan and has been petitioned for listing under the Endangered Species Act. The zoo's Mazama newt conservation efforts are conducted in partnership with the National Park Service.