Northwest Trek Wildlife Park Supports Endangered Leopard Frog Recovery
For the first time, biologists have documented zoo-reared northern leopard frogs surviving a winter in the wild at Columbia National Wildlife Refuge in Eastern Washington. The breakthrough is thanks in part to Northwest Trek Wildlife Park and the Oregon Zoo, which partnered on a zoo-based rearing and reintroduction program for this endangered species.
Invasive American bullfrogs nearly wiped out native leopard frog populations in the region, but targeted control efforts helped create a more favorable environment for the released froglets.
Zoo-Based Conservation Efforts Show Promising Results
Last August, the Oregon Zoo and Northwest Trek Wildlife Park released zoo-raised northern leopard frogs into the wild. Some of those frogs have now made it through winter—a major step forward in species recovery.
“This is great news,” said Jen Osburn Eliot, who leads the Oregon Zoo’s frog-rearing program. “We raise these frogs until they’re strong enough for release, but without bullfrog control, they wouldn’t survive. This proves that those efforts are working.”
Marc Heinzman, conservation manager at Northwest Trek Wildlife Park, added: “This is a major milestone for our work to save northern leopard frogs in Washington. Collaboration makes this possible.”
Work Continues for the Endangered Leopard Frog
Although this survival is cause for celebration, the work is far from done.
“Reintroductions like this are always difficult,” said Patricia Valcarcel, herpetologist at the Washington Department of Fish and Wildlife. “These early survivors give us hope, but we must stay committed.”
Efforts continue to manage invasive bullfrog populations and assess future release sites to improve outcomes.
A Collaborative Recovery Project
The northern leopard frog has vanished from much of its native range in Washington, Oregon, and western Canada. Listed as endangered in Washington since 1999, only one known population remains.
The American bullfrog, native to the eastern U.S. but invasive here, is a major threat. It preys on native species, outcompetes them for resources, and spreads disease.
The recovery project involves multiple partners, including Oregon Zoo, Northwest Trek Wildlife Park, Washington State University, and U.S. Fish and Wildlife Service. Funding came from a 2024 Competitive State Wildlife Grant awarded to WDFW by USFWS’s Office of Conservation Investment.
Plan a Visit to Northwest Trek Wildlife Park
Northwest Trek Wildlife Park is a 725-acre facility operated by Parks Tacoma. Dedicated to conservation and education, the park is home to grizzly bears, cougar cubs, rescued bald eagles, and more. To explore exhibits and learn about local wildlife conservation, plan your visit at nwtrek.org.