Humans wiped out a native San Francisco butterfly. Now another species is filling its 'big blue shoes'

For decades, conservationists have been restoring the biodiversity of San Francisco's coastal dunes. But a key piece of the puzzle was missing — until now. 

source https://www.cbc.ca/radio/asithappens/xerces-silvery-blue-butterflies-1.7181494?cmp=rss