Endangered Mission blue butterflies will be released today atop Twin Peaks, which ecological studies have shown to be a suitable habitat for the insects and their eggs.
A new batch of butterflies will fly free in the hills, after a successful introduction of 22 pregnant females in 2009, according to The City’s Recreation and Park Department. The department also helped release a group of 60 males and females on Twin Peaks last year, according to Recreation and Park spokeswoman Connie Chan.
“They are surviving and thriving,” Chan said. “We needed to make sure there is a full circle of life there, and we continue to find not just the adults, but the caterpillar and the eggs.”
Officials plan to collect more butterflies today on San Bruno Mountain and transfer them to San Francisco, which once served as the insect’s natural environment and provided an ample food source of the herb lupine.
The butterflies’ numbers have dropped dramatically due to urbanization, resulting in their 1976 listing on the federal endangered species list.
The project’s goal is to restore several hundred butterflies to Twin Peaks, as was seen in the 1980s.