PORTLAND, OR – Imagine walking through an open meadow along the Oregon coastline and you are surrounded by butterflies with wings of yellow-orange fluttering all around you. This enchanting scene is closer to becoming a reality as the U.S. Fish and Wildlife Service and partners are moving forward with a proposal for re-establishing two populations of the threatened Oregon silverspot butterfly.
The locations identified for potential reintroduction, both within the butterfly’s historical range, are Saddle Mountain State Natural Area in central Clatsop County and the Nestucca Bay National Wildlife Refuge in southern Tillamook County. Saddle Mountain State Natural Area, owned and managed by the Oregon State Parks and Recreation Department, has high numbers of nectar and violet plants and should be to the butterfly’s liking. Nestucca Bay National Wildlife Refuge has been actively restoring habitat for silverspots in preparation for their return.
The Service’s National Wildlife Refuge System plays an essential role in helping protect and conserve our nation’s most at risk species, including recent local conservation successes with the greater sage-grouse, Columbian white-tailed deer and Oregon chub.
At one time, the Oregon silverspot butterfly was widespread among 20 distinct locations from northern California to southern Washington. Only five populations currently remain, four in Oregon and one in California. The species gained Endangered Species Act protections in 1980 when it was listed as threatened. More recently, concern for the species has increased due to dramatic declines observed in 2014 and 2015 at all four existing Oregon sites. The Service is working with our partners at the Oregon and Woodland Park Zoos, the Oregon Parks and Recreation Department, and the U.S. Forest Service to reverse this trend, including this effort to reintroduce new populations.
To increase the likelihood of success, the U.S. Fish and Wildlife Service is proposing to designate these populations as experimental to provide surrounding landowners with assurances the reintroductions will not impose economic or regulatory restrictions on their properties.
The Service is partnering with the Oregon Zoo and Seattle’s Woodland Park Zoo, which are providing Oregon silverspot pupae for the reintroductions through their imperiled species recovery programs. Each year, a small number of female butterflies are collected from the wild and brought to zoo conservation labs, where they lay large numbers of eggs. The eggs hatch into tiny larvae, which are kept safe over the winter and released the following year to augment wild silverspot populations. These programs substantially increase the number of offspring surviving to adulthood.
The primary limiting factor for the Oregon silverspot is lack of its caterpillar host plant, the early blue violet. The butterfly needs these violets to be densely-packed and in high numbers, surrounded by other native nectar plants. This type of coastal prairie habitat was historically maintained by regular natural disturbances such as fire, but now it is very rare naturally and often must be created and managed for it to be sustained, mostly due to invasive species.
The proposed rule will be published in the Federal Register on December 23, 2016. The proposal and instructions on how to provide comments can be found at www.fws.gov/oregonfwo/. Comments will be accepted through February 21, 2017.
The U.S. Fish and Wildlife Service works with others to conserve, protect, and enhance fish, wildlife, plants, and their habitats for the continuing benefit of the American people. For more information, visit www.fws.gov/pacific, or connect with us through any of these social media channels at www.facebook.com/USFWSPacific, www.flickr.com/photos/usfwspacific/, www.tumblr.com/blog/usfwspacific or www.twitter.com/USFWSPacific.