The endangered Western Pond Turtle faces threats from habitat degradation and disease, but the biggest threat to these little turtles are invasive bullfrogs that have thrived in the Columbia River Gorge between Oregon and Washington. These huge frogs gobble up tiny turtle hatchlings like Whitman's Samplers. By breeding Western Pond Turtles and raising them until they are large enough to be off the bullfrog's menu, the Oregon Zoo is helping to rebuild the turtle population.
Preparing to storm the shores of the Columbia River Gorge
Bon voyage!
Home sweet home
Photo credits: Brock Parker / Oregon Zoo
PUBLIC CAN VISIT ZOO'S ENDANGERED WASHINGTON TURTLE HATCHLINGS
Turtles will be released into the Columbia River Gorge when they are bigger
PORTLAND, Ore. -- For almost a decade, the Oregon Zoo has been working to save endangered western pond turtles, rearing them in a protected environment until they are big enough to be released into the wild. Visitors can now view recent hatchlings - each a bit larger than a quarter - at the zoo's conservation station, located in the Cascade Stream and Pond Building.
Over the next nine months, zoo staff members will monitor and weigh the rare turtles as they grow. Once they reach a suitable size of about 70 grams, the turtles will be returned to the wild and monitored for safety.
"When we release the turtles, they're big enough that predators like non-native bullfrogs are no longer a threat," said David Shepherdson, the zoo's conservation program scientist. "The months the turtles spend at the zoo give them a real edge - scientists estimate that 95 percent of the turtles we've released into the Columbia River Gorge have survived."
Just a decade ago, western pond turtles had nearly disappeared from Washington, their native habitat, with only 150 turtles left in the wild. Today, researchers estimate there are about 1,400.
Habitat degradation and disease continue to endanger the species, but the biggest threat to fragile baby turtles is the bullfrog. Native to areas east of the Rockies, this nonindigenous frog has thrived throughout the West, driving pond turtles and a host of other small, vulnerable aquatic species to the brink of extinction.
The Western Pond Turtle Recovery Project, a collaborative effort of the Oregon Zoo, Woodland Park Zoo, Washington Department of Fish and Wildlife, and U.S. Fish and Wildlife Service, was created to help restore the species in the wild.
Every summer, wildlife recovery workers monitor female turtles in the field to determine where they will dig their nests. Once the turtles have laid their eggs, workers cover the nests with wire "exclosure" cages that help prevent predators from eating the eggs. The eggs are then allowed to incubate naturally, and hatchlings are collected in the fall.
The hatchlings are barely the size of a quarter when they are taken to the Oregon Zoo and the Woodland Park Zoo. Unlike wild turtles, the zoo turtles are fed and kept warm throughout the winter, so by their summer release, the 10-month-olds are as big as wild 3-year-old turtles.
"We make sure our turtles can hold their own before releasing them into the wild," Shepherdson said.
The zoo is a service of Metro and is dedicated to its mission to inspire the community to create a better future for wildlife. Committed to conservation, the zoo is currently working to save endangered California condors, Washington's pygmy rabbits, Oregon silverspot butterflies, western pond turtles, Oregon spotted frogs and Kincaid's lupine. Other projects include studies on black rhinos, Asian elephants, polar bears and bats.
