Spooky Spiders

Oct 27, 2011

by Lorraine Julien

Photo: Lynx spider by Nickles, John, US Fish & Wildlife Service

As though he knew Hallowe’en was approaching, a large black Wolf (Lycosidae) spider with fuzzy looking legs decided to take up residence near my kitchen door. I crept up to it very slowly with my camera but, unfortunately, I didn’t check the pictures for clarity and my spider was gone before I could photograph it again. Though they can produce silk like most other spiders, Wolf spiders do not spin webs. When the young are hatched, they cling to their mother’s body holding onto special handle hairs on her back.

The proper name for spiders is Arachnids, named after the mythological woman who was changed into a spider (Arachne) by the goddess Athena for challenging her to a weaving contest. Arachnids are some of the best architects in the animal world – spiders spin silken webs, spun from fingerlike glands in the abdomen to trap insects. The most common web is the round or Orb web while in parts of North America there are spiders that dig tunnels, line them with silk, and close the entrance with a movable door to trap their hapless prey. Another odd web is the funnel-shaped cobweb of the brown Grass Spider.

Though all spiders are creepy looking, they are valuable to have in your garden as they have voracious appetites for pest insects and do not eat plants. As a group, spiders eat tons of pest insects every year. They also eat non-pest insects such as honey bees, butterflies and praying mantises, to name a few, if they are unlucky enough to be trapped in the spider’s web.

Once the prey is secure, the spider kills it by injecting its venom and then wraps the prey in a silken cocoon for later consumption. Don’t worry, our native spiders don’t have enough venom to harm humans and most spiders don’t have fangs that are strong enough to pierce human skin. (Small consolation if you happen to find one in your bed at the cottage!) Of the thousands of spider species, there are only four in the U.S. (Colorado) that are poisonous (black widow, brown recluse, hobo and yellow sac spiders) and these are not common.

Spiders generally live for one to two years although some types such as the Tarantula can live up to 20 years. As spiders grow, they shed their exoskeleton (outer skeleton). This shedding is necessary for growth but, during this transition, they are extremely vulnerable to being eaten by other spiders. Spiders have eight legs as opposed to insects that have six legs. They’re found everywhere in the world except the oceans and Antarctica.

Reproduction is hazardous for male spiders. Garden variety spiders breed only once a year. Males roam around searching for females and usually build a small web near the female’s web. He then courts the female by plucking strands on her web. Before the male approaches the female, he makes a safety drop line to enable him to retreat quickly in case she attacks him. After mating, the male dies and is sometimes eaten by the female.

Most of the typical spider webs that we see are made by Orb weavers (Araneidae). Their webs are designed to capture prey with very fine, but strong, silk strands which spread the force of a flying insect throughout the web and lessen the chance of it bouncing out. Orb weavers have very poor eyesight but are extremely sensitive to vibrations in the web. Their webs can be as large as two feet in diameter. Spiders are the originators of “web” sites (sorry couldn’t resist).

One of our most common spiders is the Black and Yellow Garden Spider (Argiope aurantia). It has distinctive yellow and black markings on its body. This spider was the star of the book “Charlotte’s Web” and is very familiar to campers and gardeners. In a nightly ritual, the spider consumes the circular interior part of the web and then rebuilds it each morning with fresh new silk. These fine threads appear to have tiny particles of what may be miniscule and organic matter that may contain nutrition. The design of the web is different from those of other spiders as the spider spins what appears to be a vertical, white zipper-like centre in the web. It was originally thought this might be there to strengthen and stabilize the web but scientists now believe it’s there to stop birds from flying into and destroying the web.

The Jumping Spider (Salticidae family) does not build a web. They wander through the garden looking for insect or spider prey. They have little retreats with egg sacs in mailboxes, goldenrod and in the corners of windowsills. These sturdy little spiders have very good vision and the ability to jump impressive distances for their size. I’ve seen this type in our house and they are not easy to catch.

The Daddy Longlegs or Harvestmen (Opiliones) is not a spider at all but it is a close relative. They scavenge and eat very small insects. If you want to attract spiders to help control pest insects in and around your home and garden:

Use mulch on your vegetable and flower gardens

Provide places for web attachment or homes such as tall plants

Use a natural insect spray if possible and limit its use

Happy Hallowe’en!

Please feel free to report any observations to Lorraine Julien at This email address is being protected from spambots. You need JavaScript enabled to view it.  or Steve Blight at This email address is being protected from spambots. You need JavaScript enabled to view it.