There are approximately 1400 species known in Canada, including a few rare ones, 2 species of tarantulas (Antrodiaetus pacificus and Sphodros niger) and 2 species of black widows (Latrodectus variolus and L. hesperus) found in southern parts of Ontario, Alberta and British Columbia.
Spiders commonly found in Canadian homes include house spiders, wolf spiders, cellar spiders, fishing spiders, jumping spiders and (much less often) black widow spiders. Interestingly the common house spider and Black Widow spider are both in the same family. Spiders are usually found in the corners of rooms, closets, boxes, dark crevices, basements, garages, and gardens.
The spider has an unsegmented body with two main divisions and four pairs of legs. It also has organs for producing silk, which is used for making nests, webs to catch prey, or cocoons for its eggs.
Most spiders prey on insects, many of them pests. Once the prey becomes tangled in the web, the spider immobilizes it by wrapping it in more silk and then injecting venom to paralyze it. Later, the spider injects a digestive liquid and sucks out all the nutrients from its prey. Not all spiders are web spinners, and there are many types of spiders that use different strategies to catch their food. For example, Wolf spiders hunt for their prey and are especially helpful to farmers and gardeners because they prey on common crop pests like caterpillars, plant bugs, and aphids.
Spiders do not transmit any diseases. Although nearly all spiders have venom glands, they rarely bite humans, and only a few species (like the black widow spider) can have a venomous -- but not usually fatal -- bite. Most spiders are nocturnal and avoid conflict by running away. They will only bite if they feel threatened (for example, being squeezed or held).
The degree of reaction to the black widow spider bite depends on the area of the body bitten, amount of venom injected, the person’s size and a person's sensitivity to the venom. Serious long-term complications or death are rare. If bitten, remain calm, and immediately get medical attention (contact your doctor, hospital, or poison control center). Apply an ice pack directly to the bite area to relieve swelling and pain.
As previously stated, spider bites are rare; however, when doing yard work or in forested areas, take proper precautions by wearing gloves and boots, rolling pants into socks and tucking your shirt into your pants.
The 3 of the Most Common Spiders in Ontario
Yellow Garden Spider
Source: The Cosmonaut, Wikimedia Commons
Cross Orbweaver Spider
Source: Ryan Hodnett, Wikimedia Commons
Yellow Sac Spider
Source: Marcello Consolo, flickr.com
How To Get Rid of Spiders?
To prevent spiders from entering your home, weather strip or caulk windows and doors, and repair screens. When cleaning your garage or basement, or working in your garden, it is a good idea to wear gloves to avoid exposing yourself to unexpected spider bites. Spiders are generally beneficial: a few spiders left in your basement and crawlspaces will help to capture earwigs and other insects.
- Sweep or vacuum baseboards and corners of rooms often to remove any harborage areas
- Remove spider webs.
- Sweep behind washers and dryers often and rearrange furniture occasionally to prevent spiders from spinning webs in the same place.
- Keep clothing, shoes, and blankets off the floor so that spiders do not hide in them during the day.
- Use yellow light bulbs outdoors to attract fewer insects, which will discourage spiders from spinning webs near your house.