Beneficial insects

Spiders… Nature’s Outcasts

Few people like spiders. Instead, they inspire fear and revulsion, just like earwigs, sowbugs and millipedes. It has to be said that they are often portrayed in a negative light in popular culture: they are associated with dark places or horror scenes in films, or with witchcraft as in Halloween festivities.

They’re thought to be dangerous. But while all spiders on the planet are venomous because they possess a venom that paralyzes their prey, this venom does not work on humans. At least for most of the 52,000 known species, since only a dozen or so possess a venom that can lead to medical consequences. These few species are not found here in Quebec or even Canada. Fear of spiders is widespread, but don’t confuse it with arachnophobia, which is an uncontrollable and disproportionate reaction, even to the sight of a simple image.

Personally, I’m not afraid of spiders because I know they’re very useful in the garden, but I don’t want them in my house and I won’t let them run over me just yet. However, my view of these little creatures has changed considerably since two unusual characters visited my home.

Here’s a pretty spider weaving her web near my bedroom window, and she’s had lots of babies this year!Photo: Gilles Arbour.

Very Interesting Visitors

This summer, I invited Gilles Arbour, a talented naturalist and photographer, to come and take insect photos in my vast flower meadow, and he asked if he could bring along his friend and partner at Natureweb.com, Pierre Paquin, a renowned arachnologist. They arrived with ingenious homemade harvesting equipment. The first is a beating net, a kind of upside-down umbrella connected to a container, which they walked between the flowers and bushes, banging on the vegetation. The second is a sieve, which they used to collect specimens from the forest litter. This is a large tube of fabric, separated in the middle by a coarse filter to separate leaf litter from the small organisms that swarm in the humus.

Then they sorted it all out on a piece of cloth on the floor, and I could see them taking the little critters in their hands and letting them run down their arms. I’m not quite there yet, but I realize that the fear of spiders is mostly linked to a lack of knowledge and false beliefs.

Pierre Paquin in full harvest mode.

A Few Facts About Spiders

Spiders have been a real discovery for me since that visit. First of all, I had no idea there were so many of them on the planet: 52,228 spider species described worldwide, divided into 135 families. In Canada, there are 1,413 species and 43 families are known (Paquin et al. 2010b) and in Quebec, the fauna includes 708 species in 34 families (Paquin & Dupéré, in prep.). In comparison, mammals number some 5,000 species in 150 families.

The spider’s body is divided into two parts: the cephalothorax, with eight legs, and the abdomen, with spinnerets at the rear. It is through these appendages that they secrete silk, which is used to produce threads for moving around, weaving webs, entangling prey and making egg sacs. Unlike insects, they have no wings or antennae. They generally have eight eyes, but some species in Quebec have six.

Drawing of a typical spider. Photo Natureweb.com.

Some Misconceptions About Spiders

  • They don’t sting because they don’t have a dart, but all species can bite with their hooks (mouthparts) as this is how they catch their prey. Most species, however, are too small to pierce the skin.
  • They rarely bite, unless they feel cornered by clumsy handling, for example.
  • They are predators that feed on insects, not vertebrate blood.
  • Swallowing a spider during the night is an urban legend that makes arachnologists laugh a lot, especially if you put forward a precise number of specimens ingested in a year.

Precious Allies in the Garden

Spiders are valuable allies in the garden, and it’s in our interest to protect them. They cause no damage to plants, as they are predators, whether in the vegetable garden, the orchard, or in our flower beds. On the other hand, they are extremely useful in the fight against real crop pests, as they feed on a wide variety of insects such as mosquitoes, flies, aphids, mealybugs, whiteflies, butterflies and their caterpillars (such as the cabbage maggot), etc. This helps to reduce the need for pesticides.

Spiders react quickly to changes in their environment. A sudden increase in their numbers may indicate an overpopulation of insects. Spiders themselves are a source of food for other animals, such as small mammals and birds. In addition, spiders can help pollinate flowers by moving from plant to plant in search of prey. The presence of spiders is one of the signs of a healthy garden.

Argiope trifasciata and its prey. Photo: Gilles Arbour.

How to Encourage Spiders in the Garden?

To encourage the presence of spiders in your garden, here are a few simple things you can do:

  • Ban the use of all chemical products that harm biodiversity
  • Keep fallow areas or use differentiated mowing in your lawn
  • Leave spider webs in place when you see them
  • Cover the soil with mulch
  • Leave piles of stones or old low walls in place
  • Don’t destroy the egg sacs that house the next generation of predators
  • Grow a variety of melliferous plants to attract foraging insects… and prey for spiders.

Here are a few beautiful spiders that I’ve collected at home or that are common in our gardens.

Cicurina brevis. Photo: Gilles Arbour.
Eris militaris. Photo: Gilles Arbour.
Enoplognatha ovata. Photo: Gilles Arbour.
Misumena vatia. Photo: Gilles Arbour.


Pierre Paquin, biologist and arachnologist, and Gilles Arbour, naturalist and photographer, bring you the beauty, richness, ingenuity and complexity of the living world through photography, blog posts and research on Natureweb (French only).

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Edith Smeesters is a biologist and a pioneer in ecological horticulture in Quebec. She has given countless conferences and workshops and written several books on the subject for over 20 years. She founded and has been president of several environmental organizations, such as Nature-Action Québec and the Coalition for Alternatives to Pesticides. She was a key figure in the creation of the Pesticide Management Code of Quebec, which has been in effect since 2003. She has received several awards for her involvement in the environment and is a member of the prestigious "Cercle des Phénix".

4 comments on “Spiders… Nature’s Outcasts

  1. This blog is always so informative. Thanks for sharing!

  2. Interesting article, thank you. One correction though – we have black widows in Western Canada and the mature, female black widow is medically significant. There has not been a death from them since 1983 and it is suspected that it was an anaphylactic reaction to the anti-venom

  3. Diane Sanders

    I love taking pictures of all insects, enlarging the picture and seeing how fascinating they are close up. They look completely different up close and some are absolutely beautiful. Spiders are my favorite. The naked eye cannot see the intricacies of their bodies and are fascinating. Discovering all the good that many insects do for us is a learning experience. Now I pick up all insects that invade my home and release them back outside. Maybe I overdo it but I’m always pleased to see them scamper off outside.

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