Return of long-lost bees creating a lot of Presidio buzz

Image of research in field with net.

(San Francisco Chronicle) Silver digger bees began to disappear as the vast coastal prairie on the western side of San Francisco was paved over for development and were all but gone by the mid-20th century. But their recent rediscovery is an example of how the removal of invasive plants and the restoration of dunes and grasses at a former military base have helped bring back this lost species that had thrived here for tens of thousands of years before the city was built.