Wednesday, November 25, 2015

Brown Widows are Everywhere!

Well at least they are here in Orange County, California.

We are being completely overrun with brown widow spiders (Latrodectus geometricus). I've never seen anything like this. Black widows would hide in dark, secluded places, but since the brown widows showed up there are no black widows to be found. The brown widow has seemed to out-compete with its cousin the once common black widow.

Walking in the yard at night, we see all along the edges of plants, the sides of the house, the gates and fences, and anything else are brown widow spiders hanging upside-down in their webs with that telltale hourglass prominently displayed.

The brown widow spiders are fairly distinct with their long legs banded dark and light, amazingly strong webs, kind of a dark-chocolate colored body and that orangey-red hourglass. And yes they are venomous, although considered not as venomous as the black widow spider. Though still considered dangerous, it turns out their venom is the same as their close relation, the black widow spider. However, their chelicerae (fangs) are shorter that those of their black widow cousins and are therefore not able to deliver the same potentially dangerous bite. There bite should still not be taken lightly—particularly, as always, with children and older people.

The brown widow spiders are also incredibly prolific. We find several off-white, spiky egg cases in clusters—not very well hidden. We'll find the egg cases and the females under the lips and lids of trashcans and trashcan handles, under the rims of pots, under fence rails, door stoops, just about anywhere else. Typically we're finding them anywhere we are going to end up sticking our fingers to get a grip on whatever it is.

Brown widow egg cases in a metal fence fitting.



Here’s a great website with more information and some great photos:


Thanks for lookin'.