Photo by Sean McCann
Family name: Lycosidae
AKA: wolf spider Body size: with so many species, wolf spiders have a tremendous range in size, from 0.11 inches to 1.77 inches Where they live: With more than two hundred wolf spider species in North America north of Mexico, wolf spiders can be found in any habitat across the continent.
Wolf spiders are among the most ubiquitous and conspicuous spiders in North America. Whether a mama wolfie is toting her babies around your garden or a subadult is darting between blades of grass on your lawn, you likely encounter wolf spiders (whether you realize it or not) each day during their peak season, the summer.
Many researchers around the world have devoted years of their lives peeking into every nook and cranny of wolf spider biology and behavior. Because we know so much about wolf spiders, we decided to narrow the field and share with you our top ten favorite facts.
Photo by Sean McCann
• They come in every variety. Wolf spiders are extremely diverse, with nearly twenty-four hundred species worldwide and more than two hundred species in North America alone. They all are a little hairy with relatively long legs, but in terms of size, they range from smaller than a dime to bigger than a quarter. They vary in color from gray to brown and often have patterned bodies. They use silk for draglines and egg sac construction, but not for prey capture.
• They’re nothing like wolves. Though they can be a little hairy and they hunt for food, the similarities between these spiders and their lupine namesake ends there. Wolf spiders are loners and don’t hunt in packs. And when they “hunt,” mostly they sit around waiting for food to show up. When it does, they pounce on it, more tigerlike than wolflike.
• Wolf spiders live all over the place. With so many different species, they have adapted to pretty much every condition. Whether they’re running up and down beaches, tiptoeing across the Arctic tundra, hunting in farmers’ fields, or living it up in the woods, wolf spiders play valuable roles in their diverse environments. They help control populations of other animals, such as small insects, that are lower on the food chain. In addition, animals higher up in the food chain, such as birds, depend on them for food.
• They have excellent eyesight. Wolf spiders use their eight eyes to hunt and avoid predators. They exhibit eyeshine, which means their eyes glimmer when illuminated at night. Many species are nocturnal and count on their keen vision to help them nab food in the dark.
• They go with the flow. While many other spider species have fixed life histories (meaning they mate at a certain time of year, produce a certain number of egg sacs each year, live a certain amount of time, etc.), a wolf spider’s life story varies depending on where it lives, not its species. Down South, a single species can have multiple generations in a growing season, while in colder climates it might take two years just to mature. They generally overwinter as immatures and mate during springtime, but this can vary, too.
Photo by Sean McCann
• Even without a nest, they’re great at nesting. Wolf spiders don’t construct webs to provide shelter for their family. Instead, females protect their eggs by carrying their ofttimes bluish egg sacs attached to their abdomens like little Santa Clauses with sacks full of spider babies. With forty or more eggs per sac, that’s quite a load of babies to haul around. Some wolf spider mothers of the genus Pardosa help speed up their young’s development time by sunning their egg sacs on warm days.
• They make great mothers. After their eggs hatch, the young spiderling wolfies crawl up on their mother’s abdomen, where they stay for one to two weeks. All the while, their mama makes sure nobody bullies (or eats) her little babies. Spiderlings don’t eat during their free ride, but when they start to get hungry they no longer like to bunk with their brothers and sisters and release a little line of silk, from which they float to their new life in the breeze — tiny, daring aeronauts.
• They’re apparently tasty. Many animals enjoy feasting on wolf spiders. In addition to birds, cats, and other larger animals, parasitic wasps specialize in eating wolf spider eggs. When one such wasp finds a wolf spider mama carrying her egg sac, that sneaky bugger will lay her eggs in with the spider eggs. The wasp larvae eat the contents of the egg sac, setting the scene for a sad surprise when, instead of spiderlings, an abundance of well-fed wasps emerge from the mama’s sack.
• They’re speedy. Excellent runners, wolf spiders dart across open areas or between fallen leaves. Some species, however, prefer the sedentary life, constructing silk-lined burrows an inch or two beneath the ground where they just hang out, watching the world go by.
• They’re excellent communicators. When it comes to getting their message across, wolf spiders use everything they’ve got. They use visual cues, like leg waving and dancing, as well as auditory and tactile (well, vibrational) cues to attract mates. Smaller wolf spiders sniff out pheromones of larger spiders and hightail it in the opposite direction to avoid being eaten.
Cover courtesy of the University of Chicago Press
Reprinted with permission from Dr. Eleanor’s Book of Common Spiders by Christopher M. Buddle and Eleanor Spicer Rice and published by The University of Chicago Press