Nearly 400 endangered northern leopard frogs will leap back into the wild soon, thanks to a recovery effort at Northwest Trek Wildlife Park. Washington Department of Fish and Wildlife (WDFW) officials delivered the frog eggs to the Eatonville wildlife park in April.
“They’ve already grown from egg masses to tadpoles in a short time,” said Northwest Trek Zoological Curator Marc Heinzman. “At this rate, the frogs should be ready to hop back into the wild this summer.”
Once abundant throughout North America, northern leopard frogs are rapidly disappearing from their native ranges in Washington, Oregon, and western Canada. The species has been listed as endangered in Washington since 1999. With only one known wild population remaining in the state, the frogs still have a long road to recovery.
Northwest Trek, along with program partners at WDFW, U.S. Fish & Wildlife Service (USFWS), Oregon Zoo, and Washington State University (WSU), believe that raising these frogs free of predators gives them a much better chance of survival in the wild.
“We’re very pleased to participate in this critical recovery effort to help save these endangered frogs,” said Heinzman.
Keepers at Northwest Trek raise the frogs in a controlled environment, monitoring their water quality and giving them a steady diet.
The likely causes of frog decline in the Pacific Northwest include habitat loss and degradation, diseases, non-native species, and climate change. According to WDFW officials, northern leopard frogs are an important indicator of water quality due to their permeable skin. Improving and conserving wetland habitat will help frogs and other species, ranging from amphibians to waterfowl and deer.
“We hope to re-establish a northern leopard frog population to the Columbia National Wildlife Refuge in Eastern Washingon,” said Heinzman.
In late May, staff from Northwest Trek, WDFW, and WSU will tag nearly 400 tadpoles at Northwest Trek with an elastomer dye to better track them after release into the wild.
“This spring, we will release half as tadpoles into the wild and the other half later in the summer as frogs,” explained Heinzman.
The partners are all eager to learn if releasing a tadpole rather than a frog will lead to better survival. Successful conservation efforts often involve adapting strategies to identify the best outcomes for recovering a particular species.
Funding for the northern leopard frog reintroduction is provided through a competitive state wildlife grant awarded to WDFW from USFWS’s Wildlife and Sport Fish Restoration program and Potholes Supplemental Feed Route mitigation funds provided by the Department of Ecology.
2024 is the fourth year Northwest Trek Wildlife Park has been involved in raising and releasing northern leopard frogs into the wild.