A GTA field almanac
The pest year, season by season
Every pest in the Greater Toronto Area keeps a season. Each ridge is one pest across the twelve months, and the higher the crest, the busier the pest. The face on each ridge is exactly who you are dealing with. When a crest reaches your house, the calls we book most are mouse control in Toronto, wasp nest removal in Toronto, and cockroach control in Toronto.
Spring
The ground thaws and the chewers and colony-builders wake first.
Summer
The loud season: stingers, biters, and anything that breeds in the heat.
Fall
As nights cool, the outdoors moves in to overwinter where it is warm.
Year-round
Four pests keep no calendar. Indoors and heated, they never truly stop.
Seeing one of these around the house right now?
How this almanac is drawn
Each ridge is the documented activity of that pest across southern Ontario’s climate, corroborated against a 12-month Google Keyword Planner pull for the Toronto area, where searches for wasps, mosquitoes and carpenter ants rise and fall on exactly these curves. The dotted line marks the current month.
Two honest limits. The almanac is Greater-Toronto-wide: one climate sets the same timing across Toronto, Scarborough and York, so what changes between neighbourhoods is the pest mix, not the months. And the four year-round pests have no real season, so their ridges stay low and level by design rather than inventing a peak.
Sources: documented Ontario pest phenology and Health Canada pesticide guidance, cross-checked against a Google Keyword Planner seasonal search-demand pull for the Toronto geo. Reviewed September 2026.
Photographs via Wikimedia Commons, used under their licences: Carpet beetles: AfroBrazilian (CC BY-SA 3.0) • Ants: Jens Buurgaard Nielsen (CC BY-SA 2.5) • Carpenter ants: Richard Bartz (CC BY-SA 2.5) • Bees: Ivar Leidus (CC BY-SA 4.0) • Earwigs: Charles J. Sharp (CC BY-SA 4.0) • Mosquitoes & ticks: Mick Talbot (CC BY 2.0) • Fleas: Andrei Savitsky (CC BY-SA 4.0) • Wasps & hornets: Judy Gallagher (CC BY 2.0) • Fruit flies: Alexis (CC BY 4.0) • Cluster flies: Ryan Hodnett (CC BY-SA 4.0) • Spiders: Judy Gallagher (CC BY 2.0) • Mice: Ahunt (CC0) • Rats: Dunpharlain (CC BY-SA 4.0) • Cockroaches: Clemson University / USDA (CC BY 3.0 US) • Bed bugs: CDC / Dr. Gary Alpert (Public domain) • Silverfish: Francisco Welter-Schultes (CC0).