Wolf Spider Facts and Pictures
Is it Really the Big Bad Wolf?
Have you ever been out with friends, and you see a big hairy spider and someone yells, "wolf spider!"? Now the thing is, there are lots and lots of big brown spiders out there (and "big" is relative to how much you hate spiders too). Wolf spiders are the ones that have a bad reputation because they're big and brown and easy to see, and they have a fierce sounding name so people remember them. If they were called "floofy brown Betsies" or "hairy teddy bears" then most folks would probably just chalk them up to big brown things that happen to saunter through now and again. But no...a biologist long ago thought that wolf spiders hunted like wolves, in packs, and they named the family "Lycosidae." This comes from the Greek "lycosa" meaning wolf. Any time you see an "a" after a Greek name it means the critter is a predator, it eats meat. In the case of spiders, bugs and other small creatures, this particular family name is misleading because wolf spiders the world around are really solitary and don't like hunting in packs. They do pounce on prey but not quite like a wolf does. So let's get down to some real wolf spider facts and pictures.
Yes they can get big
Here are some quick facts about wolf spider species, size, and numbers:
- We've got about 240 species in 21 genera (groups) in North America (this number changes regularly because they're constantly being reclassified). You can see a complete list on BugGuide.net.
- Wolf spiders can range in size from something like the number on a watch face to the inside palm of your hand (2.5-35 mm).
- The biggest wolf spider is Hogna carolinensis, and let me tell you the adults looks big enough to saddle up and ride. They can grow up to the size of a human hand. However, they're really shy and avoid people. Scientists love these spiders because they're big and easy to track. You can read about one group that researched their sprint speed and flight. They put them on treadmills and then showed them "model predators." Who makes this stuff up?!
What to look for in North America...or "My what big eyes you have"
The best way to ID a wolf spider is by its eyes (yes, I know you don't want to get close enough to see its eyes but this is the best way, really). It has eight eyes total, with four in a row on the bottom, two large eyes above, and two medium sized eyes spaced out on the top and sides of its head. The four in a row can have two larger ones in the middle and two smaller ones outside, but regardless, there are four. So many eyes make for good hunting!
Describing wolf spiders is difficult because they have a wide range of colors and markings. Generally I think of them as brown spiders with a broad back, fuzzy body and legs, and a big furry brown abdomen. Below are some examples of different subspecies that are most common. Their abdomens and cephalothorax (sef-a-low-thor-ax), or fused head and middle) are about the same size.
These spiders also tend to be black or dark grey on their bellies and behind their knees (yes, I know you really don't want to get close enough to see this, but trust me it's true).
Wolf spiders also have three tiny hooks on the ends of their legs (tarsus) to help them grip and hold when they are running and climbing. Their front two legs can also be large and sturdy for holding prey. Compared to most spiders wolf spiders all have robust and thick legs, often marked in a very fashionable striped pattern.
Where you find them
Wolf spiders are found all across North America, and they can be found in brush, under rocks and stones, and around buildings or wood piles. Some even dig burrows. line the burrows with silk, and wait for their prey. Regardless, they are all hunters and they don't build webs. Their main habitats are deserts, grasslands prairies, open fields, grassy areas around homes, and wooded edges.
They can bite, but they're not harmful
Wolf spiders are big but they're also tiny compared to humans. They don't want to fight humans but if they are backed into a corner or scared they may bite with their fangs. They do have a mild venom, but it's not super toxic. It can hurt and make you swell a bit, but it should subside with some ice and time. My favorite sting/bite treatment is called Sting Stop. You can get it online on Amazon (Click here). (The other old favorite is a paste of baking soda and water--thick enough to stick to the spot---let it dry out completely to draw out the venom and then brush off the soda dust/residue.)
For a while wolf spider bites were thought to cause necrosis (knee-crow-sis or tissue death), like the brown recluse, studies in Australia have shown that this isn't true. Most often the bite was from a brown recluse, that had been misidentified as a wolf spider. Wolf spider bites are little worse than bites from mosquitoes or biting flies. You can read more about mis-identification of brown-recluse bites in this paper by Vetter and Bush, 2002.
Females carry their young
One of the key characteristics of wolf spiders is that the females swaddle their eggs in a ball of silk and then they carry their little baby buntings under their abdomen as they run around. When the eggs hatch the babies then hang on to the mother's abdomen like a bouffant of hundreds of eight legged baby opossums. Eventually the babies drop off.
Babies balloon, like Charlotte's Web
Baby wolf spiders can also do something called ballooning. Remember Charlotte's Web, when the spiderlings cast their long silk lines and then were carried away by the wind? Studies show that it's a way for less competition between spider siblings.
Here's a short video showing a wolf spider trying to balloon. Notice how it raises its abdomen. When it does this it's ejecting a thread of silk and trying to catch a ride on the wind.
Regardless of their size, wolf spiders are really harmless. They're not the "big bad wolf" that they're made out to be. They're just critters that have a scary name. If you leave them alone they will take care of the insects around your yard and house. Just try to appreciate their presence and give them space, and they will give you yours.
Need more help in identifying brown spiders? Try my other blog post "Introduction to Identifying Brown Spiders." If you find one in your house, and you're not gung-ho to pick them up, try the "Critter Catcher" a good solution to humanely removing spiders and insects from your house.