Butterflies were released atop Twin Peaks

Female Mission blue butterfly perched on a silver lupine seed pod, waiting for a mate. She was transferred from San Bruno Mtn. in 2009 and laid her eggs in the restored habitat Twin Peaks. (Ty Freiberg)

April 22, 2011 5:30:04 PM PDT
Several mission blue butterflies were released atop Twin Peaks in San Francisco Friday.

It is part of an effort to restore the endangered species to the area after a small population of butterfly eggs and larvae was discovered in Twin Peaks. San Francisco's Park Department along with the U.S. Fish and Wildlife services say the spread of invasive plants severely reduced the butterflies' habitat in San Francisco.

In 1976, the federal government granted the butterfly special protection.