Wolf Spiders in Michigan: A Guide to Identification, Behavior, and Control

Wolf spiders are one of the most common spiders found in Michigan. With over 125 species in North America, these hairy spiders can range greatly in size appearance, and behavior. While the majority of wolf spiders pose no threat to humans their large size and speed can cause quite a scare if one scurries across your basement floor!

In this guide, we’ll cover everything you need to know about wolf spiders in Michigan including:

• Common Species & Identification
• Habits & Behaviors
• Bites & Health Risks
• Finding & Preventing Wolf Spiders
• Safe Control & Removal

Common Wolf Spider Species in Michigan

There are around a dozen different wolf spider species that reside in Michigan. Some of the most common include

• Carolina Wolf Spider (Rabidosa carolinensis): Large and hairy, with a legspan up to 5 inches. Light brown body with dark brown stripes.

• Tigrosa Wolf Spider (Tigrosa georgicola): Medium-sized, brown body with faint stripes on abdomen. Grows up to 1.5 inches.

-Dotted Wolf Spider (Rabidosa punctulata): Tan to dark brown with rows of dots on abdomen. Up to 2 inches long.

• Pirate Wolf Spider (Pirata insularis): Smaller species, dark brown with white stripes on cephalothorax. Under 1 inch long.

• Shore Wolf Spider (Arctosa littoralis): Sandy-colored spider that inhabits beaches and sand dunes.

Wolf spiders can be identified by their large, hairy bodies, robust legs, and eyes arranged in three rows. They range in color from light tan to dark brown or black. Many species have stripes, spots, or other markings on the abdomen. The Carolina wolf in particular is very hairy.

Juvenile spiders look similar to adults but are much smaller. Female wolf spiders are generally larger than males.

Habits & Behaviors

Wolf spiders are unique in that they don’t spin webs to catch prey. Instead, they hunt by chasing down their food. During the day, wolf spiders take cover under rocks, logs, and leaf litter. At night, they emerge to actively hunt insects, spiders, and other small prey.

Some species burrow holes or dig shallow pits under objects which they use for shelter. Female wolf spiders carry egg sacs attached to their spinnerets until the spiderlings hatch. After hatching, the young spiders climb up on their mother’s back and ride around with her for several weeks.

Wolf spiders possess excellent eyesight and can spot prey during the day or night. They use camouflage to ambush prey as it passes by their hiding spots. Once spotted, they pounce out and run down their target. Their speed and agility make them successful hunters.

Though wolf spiders wander far from their daytime hiding spots when hunting at night, they don’t venture too far into homes or populated areas. They may accidentally end up indoors if they wander in through cracks, open doors and windows, or hidden within transported materials.

Bites & Health Risks

Wolf spiders have a venomous bite, but they are not considered dangerous to humans. Bites mainly occur when spiders are accidentally disturbed or handled roughly. The venom is comparable to a bee sting in potency.

Wolf spider bites cause mild reactions like:

• Instant pain similar to a bee sting
• Redness and mild swelling
• Itching or burning sensation

Rarely, more severe symptoms may develop like nausea, headache, and dizziness. Serious allergic reactions are unlikely. Seek medical attention if bite symptoms worsen or don’t improve within a few days.

Wolf spiders are not aggressive and only bite in self-defense. Female spiders defending an egg sac can be more prone to biting. The spiders themselves are not poisonous or toxic if ingested.

Finding & Preventing Wolf Spiders

In Michigan, wolf spiders are most active between April and September during warmer months. They can be found throughout the state in wooded areas, beaches, parks, gardens, meadows, and grasslands.

Wolf spiders may take shelter in man-made structures when the weather turns cold. Look for them under decks, porches, sheds, woodpiles, and similar outdoor harborages. Indoors, they inhabit basements, crawl spaces, garages, and first floor rooms.

To deter wolf spiders from your home:

• Seal cracks, crevices, openings around windows/doors
• Remove debris piles and clutter near foundation
• Install yellow bug lights at entrances
• Dehumidify basements and crawlspaces
• Clear tall grass and vegetation near home

Safe Wolf Spider Control & Removal

If you spot a wolf spider inside, avoid direct contact with the spider. Instead, trap it under a cup or jar and slide paper underneath to contain it. Release the spider outdoors far from your home.

For ongoing issues or severe infestations, contact a pest control professional. Treatments may involve residual pesticide sprays along baseboards, window frames, and corner cracks where spiders enter. Outdoor barrier sprays can also be applied.

Sticky glue traps and spider proofing tactics like sealing entry points also help reduce indoor populations. Vacuuming and cleaning away webs/egg sacs helps remove spiders and eliminate harborage sites.

In most cases, wolf spiders found in the home are accidental invaders, not a true infestation. Ongoing presence likely indicates there are entry points for them to sneak inside that should be sealed. Proper sanitation and exclusion tactics limit shelter and food sources so fewer spiders take up residence on your property.

The Bottom Line

Wolf spiders are large, common spiders that actively hunt insect prey. While their appearance can be startling, wolf spiders pose minimal risk to people and pets. Their venomous bites cause mild, localized reactions treatable at home. Limit spiders indoors through proper exclusion measures and sanitation. Population control involves traps, targeted pesticide use, and sealing off entry points into the home. With vigilance and preventative action, wolf spiders can be safely managed around Michigan homes.