From The East Bay Times
Aggressive yellowjacket populations are booming this year in the Bay Area as reports of complaints about nests hit records in some areas.
Winter rains produced plenty of insects to eat, which helped wasp nests thrive, insect experts say. Hot September weather — like the Labor Day heat wave — spurred the insects to hunt more aggressively for food, increasing the opportunities for human encounters of a painful kind.
Vector control districts in Santa Clara and Alameda reported an unusually high number of public calls about yellowjackets, while Contra Costa is on pace to break its all-time high for yellowjacket service request of 972 set in 1999.
Public calls for help with yellowjackets have increased 83 percent in Contra Costa County so far this year. The vector district received 858 calls through Labor Day this year, up from 469 at the same time last year and more than the 744 calls during all of 2016, the district reported.