Beneficial Arachnida and How to Attract Them: Wolf Spiders

If you have seen a large, hairy spider with long legs  in your garden it might be a wolf spider.  Actually wolf spider refers to a family of spiders and includes over 3,000 species world wide and 200 species in North America.  The name comes from the fact that these spiders chase their prey and pounce on them (like a wolf).  Wolf spiders can be distinguished from other spiders by the arrangement of their eight eyes in three rows; the lowest row has four small eyes, the middle row two large eyes, and the top row two small lateral eyes.

Since the name wolf spider refers to a whole family of spiders there is considerable variation in appearance.  Most are brown or gray, often mottled with blotches or stripes, and between ¼ to 1½ inches in length.  They live alone on the ground often under shrubs and grasses where there favorite prey, insects, reside. They also hide under rocks and other objects, although some dig borrows.  Since they are active hunters, they do not spin webs, and they locate their prey by sight and sensing vibrations.   A male attracts a  female by rhythmically waving his second set of appendages called the pedipalps which he also uses to transfer sperm to the female.  The female of many species wrap the dozens of eggs she produces in a large ball of silk which she carries on her abdomen until the spiderlings hatch. When the eggs hatch the young spiders look like miniature adults and they crawl on the mother’s back where they remain for several weeks until they can go off on their own.  They shed their exoskeletons several times before becoming adults.  Male spiders live about a year but females live several years.

Paralleling the great diversity in appearance among wolf spiders,  is a great diversity in their diet.  Most wolf spiders are nocturnal and eat a variety of ground dwelling  insects including beetles and grasshoppers, other Aracnida including other wolf spiders, as well as amphibians, and reptiles that they can find at night.  They may attack prey as large or larger than themselves.

Wolf spiders rarely come into a house and provide no real threat even if they do.  They can bite but the bite only causes problems in people who are allergic.  Since they eat insects, many of which are agricultural pests, the wolf spider is considered a benefit.  Unfortunately, they do not discriminate between good and bad insects when they select their dinner, but they are a net benefit to a garden and should not be killed unnecessarily.

To attract and maintain a population of wolf spiders provide a suitable habitat and food source.  Organic mulches like leaves and grass clippings and a wide selection of native plants including shrubs will give the spiders the cover they need and access to the insects the feed on.  Avoid pesticides.