(Portland, OR) -- The Oregon Zoo is raising 17 northwestern pond turtles that have just hatched. They're about the size of a walnut. They'll continue to grow until next spring when they're released into the Columbia River Gorge. When the turtles are small, they're a prime meal for bullfrogs. The American bullfrog isn't native to the gorge. By raising the turtles until they're larger gives them a fighting chance to survive.