The Trapdoor Spider Came In From The Rain

With streaks of lightning and claps of thunder an October storm brought well-needed rain to Southern California. While the rest of the country is preparing for the white blanket of winter, our native plants are waking up from a dormancy that helps them survive the hot dry breath of summer.

In the rain the mallow rejoiced and unfurled new blooms.

The katydid rode out the storm on her rose perch. While the days are growing cooler, she still has a month or so to enjoy the new growth.

One hillside resident, however, did not welcome the rain. Damp and homeless, she wandered in under the kitchen door seeking shelter. She stumbled into the web of a cobweb spider and was stuck there about an inch off the ground.


I was startled at first by the size of this visitor. Including her legs, she is about the size of a quarter. At first I thought she might be a young tarantula, but upon closer inspection she has the glossy brown cephlothorax of a trapdoor spider. While a relative of the tarantula, this spider has a softer, more vulnerable appearance. She’s kind of like that geeky cousin with the pale skin that seemed allergic to the sun.

The trapdoor spider colony on our hillside has included 17 locatable and occupied borrows. I haven’t counted in resent months, but it’s usually easy to spot 4 or 5 at any given time. While chance encounters have occurred when underground burrows were mistakenly dug up, I have never seen one of these homebody spiders out walking around.

I’ve seen them holed up with a brood of offspring. Baby trapdoor spiders.

And last spring, heavy rains caused one poorly placed burrow to be damaged. Damaged trapdoor spider burrow.

Did this young female trapdoor spider loose her home in the rain? There doesn’t seem to be any major mud flow areas in the yard.

Was she uprooted by the gopher that has been tunneling on the hillside and relocating dirt where no one wants it? It could be. But if she came from this far section of the yard, she walked at least 50 yards to get to the back door.

Maybe she lost her home to a foraging skunk some time ago and had yet to find a suitable hole when the rain came? Yet, she seems plump and healthy, not a spider on the edge of survival.

A female trapdoor spider spends her whole life in the protective confines of a tunnel. Walking around, she is vulnerable to the California towhees hunting in the leaf litter, skunks prowling at night, and even the wolf spider that seems to have devoured all of the cobweb spiders in the chicken house. While a male might go out looking for a mate, the large rounded abdomen and small pedipaps between her front legs and fangs tell us she is indeed a female.

What is this shy young girl doing wandering about in the big wet world? I don’t know.

While it is fascinating to see out of her tunnel, the yard needs her as a predator and she needs a natural location where she can build a comfortable tunnel burrow. When the rain stops and night falls, I’ll return her to the hillside where she belongs.