Occasional Invaders
Spider
Eight-legged predators found in nearly every home. Most Ontario spiders are harmless and eat other insects, but heavy webbing and large numbers are a nuisance.
Quick facts
- Size
- A few mm to over 5 cm with legs
- Colour
- Grey, brown, black or patterned
- Active season
- Year-round; most visible late summer and fall
- Where found
- Basements, corners, windows, garages, decks, docks
How to Identify
- Eight legs and two body sections
- Common local types: house, cellar, wolf, orb-weaver and dock spiders
- Most build webs; wolf and dock spiders hunt on the ground
Signs to Look For
- Webs in corners, windows and light fixtures
- Egg sacs (small silk balls)
- Spiders in basements and garages, especially in fall
Why It Matters
- Most are harmless; bites are rare and usually mild
- Webs make homes, decks and businesses look neglected
- Large numbers often mean plenty of other insects to eat
Prevention Tips
- Vacuum webs and egg sacs regularly
- Seal gaps around windows and doors
- Reduce outdoor lighting that attracts insects
- Keep basements and garages free of clutter
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