Beautiful wolf spider mothers tote their egg cases slung beneath the abdomen to reduce chances of their young falling victim to predators or parasitoids.
Last week we visited funnel weaving spiders whose gossamer webs were revealed by morning mist on low-lying vegetation outdoors. This week we take it indoors where early each morning for the past couple of weeks I have been greeted by smallish wolf spiders dashing across the bedroom floor, cruising the bathroom, slipping around the sink, and audaciously reclining upon my recently made bed. What’s up with this? In previous episodes we met several famous and more notorious home invaders, including brown marmorated stink bugs, multicolored Asian lady beetles, and boxelder bugs. Take notice: spiders enter homes as well!
Small wolf spiders dashing about the bedroom floor, roaming the bathroom, slipping around the sink, or resting on the bed provide an opportunity for honing one’s spider catching skills first thing in the morning.
Wolf spiders are among the most important invertebrate agents providing the ecosystem service of biological control by devouring caterpillars, leaf hoppers, lace bugs, and just about anything else they can sink their fangs into. As generalist predators, they eat a broad range of prey and are vitally important in putting a beat-down on insect pests not only in agricultural ecosystems but also in residential gardens and landscapes. During this growing season as I tended my flower beds and vegetable gardens, I was amazed at the abundance of wolf spiders dashing through the mulch and hiding beneath border stones lining the gardens. As summer wore on, female wolf spiders were regularly seen toting their dazzling white egg cases slung beneath their abdomens. By late summer and early autumn after these eggs hatched, busy mothers toted scores of tiny spiderlings upon their backs, safe from hungry jaws of other ground-dwelling predators.
In a basement room, a mother wolf spider carries dozens of spiderlings on her back until they are old enough to fend for themselves.
On more than one occasion, I have discovered an egg-laden female wolf spider sneaking along the baseboard where wall meets floor in the playroom downstairs. Such discovery ends with the capture of the mother-to-be and the subsequent relocation of said spider to the garden where food abounds. Apparently, this year one such female avoided detection and fulfilled her motherly role of producing a brood of hatchlings somewhere in my home, hence the ongoing excitement of discovering small wolf spiders in bedroom, bathroom, and round about my home at 5:30 each morning. While this might generate terror for arachnophobes, for a bug geek these misplaced youngsters provide a refreshing opportunity to limber up while giving chase and corralling these rascals in a drinking glass. Once captured they are released outdoors to fulfill their spidery roles of hunting pests in my garden. After relocating about a dozen small wolf spiders over the past two weeks, several days have passed without a spider sighting. With the onset of chillier weather, this year’s wake-up call to spiders appears to have come to an end.
Outdoors, large wolf spiders can be found under stones, resting with young on their backs, or devouring hapless prey with powerful fangs.
Acknowledgements
We thank spider-loving Ashley for providing inspiration for this episode. The interesting review “Spiders as biological control agents” by Susan Reichert and Tim Lockley provided background information.