Who’s Afraid of the Big Bad “Wolf Spider”?

By Michelle Ramsey, Butte County Master Gardener, August 23, 2013

The scary-looking, ominously-named wolf spider is actually a beneficial insect.  Wolf spiders belong to the class Arachnida andare members of the family Lycosidae (derived from the Greek word lycos, meaning wolf). Wolf spiders stalk their prey like wolves do; they do not spin webs or use silk to subdue prey.  They are fast-moving, aggressive ground predators with excellent eye sight (helped in no small part by the fact that they have eight eyes, arranged in three rows: the first row has 3 small eyes, the second has 2 large eyes and the third row, closest to the top of the head, has 2 medium-sized eyes).  They are nocturnal and hunt for insects mainly at night. They are likely to be found on the ground in open areas like farm fields and grassy environments, or harboring in ground tunnels, amidst pieces of firewood or debris. There are more than 2000 wolf spider species, with body sizes ranging from less than one millimeter to 30 millimeters (.04 to 1.2 inches).

Wolf spiders provide natural control of harmful insects.  The Carolina Wolf Spider (Hogna carolinensis) is the largest of the wolf spiders.  It is brown with black markings.  Its body can measure more than one-inch long (and the whole spider can measure 4 inches across, from legs to legs).  Female wolf spiders are larger than males; their undersides are solid black.  Because some wolf spiders are large and hairy, they are sometimes mistaken for tarantulas.

Wolf spiders are not known to be aggressive but will bite if provoked or threatened. Their bite is not considered dangerous to people but it can be painful (like a bee sting).  When disturbed, they will retreat very quickly.

Young wolf spiders hatch from eggs and look like tiny adults. They shed their skin as they grow. Males reach maturity from spring to summer.  Mating occurs in autumn and the males die before the winter begins. Females lay eggs soon after mating. They carry their egg sacs in a silk cocoon attached to their abdomen by spinnerets.  The spiderlings hatch in June and July and attain only half of their full size by the following winter. After hatching, the spiderlings cling to the mother’s body for about a week before detaching. They too will overwinter and complete their growth the following spring and summer. Female wolf spiders may live for several years. It is common to find females carrying their young spiderlings on their backs during the summer months. They can be a common pest in the fall when they begin to seek shelter from cooling temperatures. 

The wolf spider is a solitary creature, preferring to live and hunt alone. Most are wanderers without a permanent home; however some Carolina wolf spiders create deep tubular burrows to live in.  While wolf spiders prefer to live outdoors on the ground, they may occasionally wander indoors, where they might be found around doors and windows, and in garages.  They may be seen running across the floor when disturbed. To keep spiders out of your home, seal cracks, gaps and other openings.  For immediate and long-term control of wolf spiders, physical removal and/or destruction of the individual spider may be the best control.

For further information visit: http://www.ipm.ucdavis.edu/QT/commongardenspiderscard.html