LA losing its native black widow spiders

This is a bit of follow-up to a post that Ellen Alperstein wrote for our Native Intelligence blog in 2012. Ellen explored the realm of spiders in Southern California, especially their activity in the autumn, and included a data point that the only native venomous spider here was the female black widow — but that the non-native African brown widow had been discovered and was coming on strong. She spoke to experts at the Natural History Museum, including entomology volunteer Jan Kempf. Now comes a piece at KCET's website that also talks to Kempf and updates the story to say that brown widows are winning out and the old familiar (but scary looking) black widows are becoming more and more scarce around Los Angeles.

Nowadays, kids are less likely to run into a black widow, though that hourglass is still a good indication of danger. That's because black widows in the LA area have largely been replaced by their cousins, the brown widows, who also bear a characteristic reddish hourglass. And a citizen science project started by the Los Angeles County Natural History Museum has helped document the change.

The story of brown widows in Los Angeles begins in 2002. According to Brian Brown, entomology curator at the Natural History Museum of Los Angeles, that's when the museum began encouraging Angelenos to capture spiders from their houses and backyards and bring them to the museum. Since the Spider Survey citizen science program started, more than 1,000 families have contributed more than 5,000 eight-legged specimens to the museum's collections. "They brought them in every conceivable container you can imagine," says Brown, including one empty bottle of Chanel No. 5.

But Brown isn't a spider expert; his passion is tiny flies. The job of identifying every specimen falls instead to museum volunteer Jan Kempf.

As a child, Kempf was already intrigued by the natural world. She was the sort of kid who chased after lizards in the backyard. That might explain why she began docent training at the museum twenty-six years ago. At the end of the training year, participants had to present a research paper. "I decided to research something I didn't know anything about, and it ended up being spiders," she says. She was hooked. She began taking classes in her spare time on spider biology and spider identification. Before long she met Brown, and she quickly transferred from the docent program to volunteering in the entomology department.

The photo above is a brown widow, from the Center for Invasive Species Research.