by the Editor & Assistant Editor
Our fall was enlivened by an entertaining OMVNATalk discussion that some of you may have missed. Proximity to Halloween may have had some connection to ‘Spidergate’. We thought we would add our little bit.
First, the authors would note that until they moved here, they had never seen so many spiders. Do we have the perfect climate and ecosystem here for these sometimes too friendly 8-legged creatures? Our first week here the editor, visiting a disused shed in the back yard, returned completely entangled in the spider webs that are so difficult to remove because of the amazing strength of spider silk. Some of us welcome our spiders; others don’t appreciate their bug-controlling efforts. Black widows (see below) eat cockroaches and flies in large quantities, thus saving your home from these pests, analogous to the Thai practice of having cobras in your garden to control the rat population. If you don’t appreciate the spider webs around your house and yard, you can try to eliminate them, but you may have little luck, as spiders have evolved to be great producers of spider webs (except for those like wolf spiders and jumping spiders who’ve adapted to other hunting techniques).
First a note about the more unpleasant local spiders–if you are bitten by a spider and develop a necrotic (very unpleasant term) skin lesion, don’t let the doctor tell you that you were bitten by a brown recluse spider–we don’t have any resident populations of brown recluses (Loxosceles reclusa). There are many other sources of necrotic skin lesions besides the dreaded brown recluse–staph, strep infections, and flea and tick bites. We also have our own quasi-local varieties of recluse spiders: Loxosceles deserta in southern California deserts, plus some imported from Chile, Loxosceles laeta, in areas of Los Angeles. Insist on scientific accuracy from your doctor. The variety can easily be determined by microscopic examination of the violin-like pattern on the back of the spider that bit you. If you want to look yourself (carefully), brown recluses are about 3/4” in total length, with a 3/8” body length, six eyes arranged in 3 pairs, and a violin shaped marking on their back. They don’t build webs to catch prey, but they do build little silk shelters to hide in during the day. You might also wish to check websites like http://spiders.ucr.edu/necrotic.html or http://www.venombytes.com for more information.
Our other local troublemaking spider is the western black widow, Latrodectus Hesperus, a very attractive, glossy black spider, with a red or orange hourglass marking on the underside (be careful when you turn the spider over to check this). Only the larger females are dangerous (again caution is suggested when checking for the sex of the spider), ranging up to 1-1/2” to 2” in overall size with a ½” body. They pick secluded, protected locations to spin sloppy 3D webs that are rather unaesthetic, in contrast to the orb weaver’s efforts.
Finally to our orb weavers–the spider variety, Araneidae, that started Spidergate–these spin very nice circular webs that are best admired on a foggy morning, when the dew will show you the amazing workmanship. These spiders, as large as 2” in overall size, are not likely to go after you. Given a chance, they will scurry off to their little silk spider shelter at one edge of the web to hide from the approaching monster. If you do manage to convince one to bite you, the effect is no worse than a bee sting. Our policy has been to leave the spiders and the pretty webs alone and watch the spiders work at their job of catching bugs for dinner.
Spin your web, spider,
Just not across my doorway
Enjoy your fall feast
Spiders are scary
Dangling, creeping and crawling
But no bugs around!
The spider not seen
That comes out only at night
Should stay in Texas!
Black widows scare us
Though they’re not very hairy
Is time the issue?