Why we love spiders
Yes, they really are good for our gardens!
The scientific name for the spider is “arachnid”. This name has its source in a Greek myth about a princess named Arachne. Arachne was an expert weaver whose fame eventually reached the ears of the goddess Athena. Athena decided to challenge her to a weaving contest, but she underestimated Arachne’s skill and lost. Overwhelmed with jealousy, Athena turned her into a spider to spin silk forever.
We all know that birds are incredibly helpful of getting rid of insect pests, but did you know that spiders are highly skilled at this as well? No other creature eats as many insect pests. And since they are especially attracted to the good eating available in diversified gardens, these eight- legged creatures can be counted on to go after the insect population when they show up in our gardens at home.
Spiders will go after flies, mosquitoes, moths, beetles, wasps and other insects around our homes and gardens. However, they don’t discriminate. They also eat beneficial creatures: ladybugs, honeybees and butterflies. But the harm they can do is far outweighed by the good.
There are more than 3,000 spider types in North America and an amazing 38,000 species worldwide. They have spent more than 300 million years on this planet, with successive generations becoming increasingly complex, highly skilled and differentiated.
One classification method divides this vast population into two groupings – “hunters” and “web spinners” – referring to the core techniques the spiders use to catch their prey.
The “web spinners” – there are some 3,000 spinner species – are the more visible and known for the silk nets they create to ensnare their prey. The orbs are web sheets formed into wheel-like shapes; built with an amazingly sturdy thread that emerges as liquid silk from the spider’s abdomen and, manoeuvred by their creators into upright position, these webs have proved through the ages to be highly effective traps for flying insects.
“Hunter” spiders represent a much larger population, embracing a very large number of families. They have
developed a huge variety of methods for catching prey. Scientists will tell you that what most hunter methods have in common, though, is the fact they don’t use webs. Hunter species include wolf spiders, jumping spiders, the super-numerous, widely dispersed night crawlers and copycat sac spiders (which tend to make their homes in vegetation and some buildings) and crab spiders.
These spiders-hunters might employ speed and strength as a tactic on their hunt, or camouflage combined with an element of surprise. Or the spider might change its colour to match its background, or simply sit in a flower patch exploiting its scents and other features to attract butterflies and other insects. Ingenious ant-mimicker spiders (yes, that’s their name) will turn themselves into faithful copies of the insects, transforming their legs into antennae, the shells on their backs into separate heads and thoraxes – a deception that readily wins them entry to an ant’s nest.
Spiders’ homes – as varied as the species itself – can be a lush bush; a deep or shallow burrow; a neat, selfcrafted tunnel; a banana leaf; leaf litter; tree roots; or human habitat. Many spiders hibernate in winter, emerging in spring just in time to meet up with newly-awakened insects and some good spring meals.
Life for the spider isn’t all work and no play – though on the matter of mating there are some interesting twists. “The coupling of two predatory and often short-sighted creatures can be a hazardous affair,” scientists tell us. The female is usually larger than the male – often MUCH larger. Her cannibalistic tendencies are aroused. And yes, the male is going to have to work very hard, with some fancy footwork, to convince the female he’s not her prey.
Humans, it should be said, have very little reason to fear spiders – though in fact many of us do. Yes, spiders carry some venom for selfprotection, but usually too little to do more harm than a mosquito bite. Spiders only bite humans in selfdefence, and we’re told there were only about 100 reliably reported human deaths from spider bites in the 20th century. Enjoy your yard. The hunters and spinners are out there right now, working on it.
Although many spiders catch their prey by spinning a web, there are also many like the wolf spider (above right) that catch it by deception.