Wakey, wakey! Zoo rouses 3,500 caterpillars for trip north

March 1, 2013 - 11:51am

WDFW aims to reestablish endangered Northwest butterfly in central Washington

Over the past two weeks, Oregon Zoo conservationists have roused more than 3,500 Taylor's checkerspot caterpillars from their winter dormancy, transferring the tiny larvae to "wake-up chambers," where they have been eating voraciously, according to zoo butterfly keeper Mary Jo Andersen.

For the eighth year in a row, the zoo's butterfly conservation lab has successfully reared thousands of checkerspot larvae, making significant progress in the effort to save this endangered Northwest butterfly.

Rearing the rare butterflies comes with many challenges. One of the most difficult tasks is feeding the ever-munching larvae, which require vast quantities of specific plants. Thanks to the zoo's horticulture department, the checkerspot caterpillars are able to feed on one of the plants their species eats in the wild: narrowleaf plantain.

This level of care is crucial: The Taylor's checkerspot butterfly is listed as endangered in Washington state and is under review for federal listing. (Oregon does not include invertebrates on its list.) While the butterflies themselves are small, they are important pollinators and have a big impact on their ecosystem.

Next week, the Washington Department of Fish and Wildlife plans to release most of these well-fed caterpillars on prairies in central Washington, where some of the region's best checkerspot habitat remains.

"Releasing caterpillars reared at the zoo is part of our ongoing effort to reestablish this imperiled species at sites where it once was abundant," explained Mary Linders, a species recovery biologist with WDFW. "Without large, connected populations, the butterflies struggle to survive."

The caterpillars will finish developing in the wild, first turning into chrysalides and then hatching as adult butterflies. After eight years of working to grow the number of endangered checkerspots, Andersen says the effects are visible.

"Biologists are now documenting Taylor's checkerspots at sites where they've been absent for more than a decade," Andersen said. "As a zookeeper and animal lover, it's great to be involved in a conservation process that puts thousands of animals back into the wild each year."

Around 150 of the caterpillars were not scheduled for release and will finish their transformation at the zoo. Adult butterflies will then breed and lay eggs to start the process all over again for next year.

Committed to butterfly conservation, the Oregon Zoo is a charter member of the Association of Zoos and Aquariums' Butterfly Conservation Initiative, a collaborative effort among nearly 50 zoos and aquariums. The zoo works in partnership with and receives funding from the Washington Department of Fish and Wildlife and Joint Base Lewis-McChord and its Army Compatible Use Buffer program to rear checkerspots and release them into the wild. Additional project partners include the U.S. Fish and Wildlife Service, the Xerces Society and the Sustainable Prisons Project administered through The Evergreen State College and Mission Creek Corrections Center for Women.

Learn more about the Oregon Zoo's effort to save Taylor's checkerspots and other imperiled Northwest species.