My husband David first read about the Mt. Diablo tarantulas in the San Francisco Examiner Sunday edition. With his characteristic vigor he exclaimed, “Got to go see them!” and within the hour we left with our three kids. It was October and that’s when male tarantulas go wandering to find mates. The day was hot, the folding hills of Mt. Diablo golden. “Look there!” David exclaimed as we drove up Northgate Rd. He had spotted our first tarantula casually crossing the pavement.
We crouched down on the centerline to admire it; then picked it up with cupped hands. Our youngest son Clive held his arm out so the spider could walk up it. We held hands underneath to catch the spider should it fall. We knew that tarantulas are not poisonous to humans and were highly unlikely to bite. Perhaps we shouldn’t have picked it up but we were careful and soon enough we set it on its way unharmed.
This is what I hoped would happen on my trip to Mt. Diablo yesterday. The hills were still golden in the autumn light, just as they had been before. An added delight was that the elevation was high enough that I was above the smoke line from the California wildfires. I did not see any tarantulas, although I did see a female tarantula nest. The silk surrounding the hole indicated that she was still inside. The silk makes it easier for her to slide inside and out. Had she already mated? I don’t know. I’d read that she puts a web of silk over her hole when she’s ready to mate. The male taps on this webbing to announce his presence.
I spoke to two park personnel about where I might see tarantulas. One told me “They are everywhere!” but the gentleman at the visitor center said he’d seen only one this year. “I think there are fewer tarantulas than there used to be. And now they seem to come out more in August and September than in October.” He added, “And they don’t like direct sunlight, so you’re more likely to see them in the evening or morning.”
I hiked several trails and stayed until after sunset, even briefly considering sleeping in my car overnight (outside the park entrance) to see if I found any early next morning. I hadn’t paid for camping, although I will next time. The campground was open and there were several vacant spots.
I would highly recommend this field trip, even though I didn’t see tarantulas. The park is lovelier than I remembered: vast acreage of beautiful oak covered hills and tremendous views from the peak. There are other reasons to go, too. I will talk about them on another post. Next year I will go in September and camp.
Science Without a Laboratory 