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Pest Library · Residential Pest

Norway Rat

Metro Vancouver's ground-and-basement rat — thicker, heavier, and more burrow-driven than its roof-rat cousin.

Norway Rat (Rattus norvegicus) — specimen photograph for identification reference, The Wild Pest field guide.
Norway RatRattus norvegicus. Field guide specimen photo, The Wild Pest reference library.

Identification

Rattus norvegicus is the larger and more common of the two rat species in Metro Vancouver. Adults weigh 200 to 500 grams, with a heavy body 18 to 25cm long plus a tail shorter than the body (15 to 22cm). Fur is coarse, brownish-grey on the back fading to pale grey on the belly. The face is blunt and heavy-jawed, the ears are small and close-set to the head, and the eyes are relatively small — all adaptations to a ground-dwelling, burrowing lifestyle. Droppings are 15 to 19mm long with blunt ends, shaped like olive pits. Norway rats are excellent swimmers (they use Metro Vancouver's storm-sewer system as a transit network) and strong diggers, but poor climbers compared to the roof rat.

Habitat in BC

Norway rats dominate ground-level and below-grade habitat across Metro Vancouver — burrows in yards, compost piles, under decks and garden sheds, in basements, garages, crawlspaces, and along the storm-sewer system. They prefer protected outdoor nesting with reliable food access: a compost heap 20 metres from a back door, a chicken coop, a backyard fruit tree, a commercial dumpster. Infestations are heaviest in the pre-1985 housing stock of East Vancouver, Strathcona, the Downtown Eastside, New Westminster uptown, and the older parts of Burnaby and Port Moody. Waterfront and ravine-adjacent homes across the region also see sustained pressure. Per our internal 2026 Vancouver Rat Report, four neighbourhoods — East Vancouver (V5K/V5L/V5N), Strathcona/Hastings, Marpole, and New Westminster — account for 63% of year-over-year Norway-rat callout growth.

Signs you have norway rat

  • Droppings 15–19mm long, blunt-ended, in kitchen drawers, pantry corners, garage base plates, or along crawlspace joists.
  • Greasy rub marks along baseboards, behind appliances, or on joist edges — from fur oils on frequently travelled routes.
  • Gnawed weatherstripping, chewed plastic utility conduit, or tooth marks on wooden sill plates at foundation level.
  • Burrow openings 5–8cm wide at the base of decks, sheds, compost bins, or retaining walls.
  • Scratching, gnawing, or dragging sounds low in walls, in the crawlspace, or inside the kitchen stud bay after dark.
  • A musky, concentrated ammonia smell near the area of heaviest activity — urine buildup in nesting material.

Risk & damage

Norway rats carry documented public-health risk. Leptospirosis is transmitted through urine contamination of standing water or food surfaces, with confirmed BC cases each year. Salmonella, hantavirus (rare in Rattus but documented), and rat-bite fever are all possibilities. Mechanical contamination of food-storage areas is near-certain where a rat population has been active more than 30 days. Structural risk is significant: Norway rats chew wiring insulation (a documented fire cause in BC Fire Services residential reports), gnaw PEX plumbing, damage weep systems, and burrow undermining foundations and garden walls. For food-service premises under Fraser Health or VCH, a single sighting triggers mandatory remediation.

Seasonality in Metro Vancouver

Metro Vancouver's Norway-rat calls run heaviest from late August through March, peaking in October and November as rats move from outdoor burrows into structures ahead of winter. Breeding continues year-round in our climate — Rattus norvegicus can produce 5 to 7 litters per year with 6 to 12 pups each — but is most intense in spring and early fall. The 2025–2026 winter was unusually mild, which did not cull juvenile rats the way a normal BC winter does; combined with the 2023 provincial SGAR ban and 2023–2024 construction churn across central Burnaby, the West End, and Mount Pleasant, the 2026 population is meaningfully elevated. Expect sustained pressure through the next 18 months.

Treatment approach

Our rodent protocol treats Norway rats as a building-science problem, not a bait problem. Step one is a full exterior perimeter audit plus attic, crawl, basement, kitchen, and garage inspection — every active and potential entry point is documented with photographs. Step two is exclusion sealing: steel wool and copper mesh at small gaps, hardware cloth at vents and soffit openings, weather-resistant sealant at penetrations, concrete patch at weep-hole damage. Step three is first-generation-anticoagulant bait stations (tamper-resistant, SGAR-compliant under BC's 2023 regulation) and snap traps deployed at activity hotspots. Step four is two 15-day verification visits with photo documentation. We do not use SGARs, and we do not leave rodents to die in walls — glue traps are never part of our protocol.

When to call a professional

Call immediately if you see a rat indoors, if you hear scratching low in walls after dark on consecutive nights, if you find droppings larger than 10mm, or if you see rub marks along baseboards. DIY snap trapping can catch surface rats but will not address entry points, and a Norway-rat colony that has been active for more than 30 days will outpace homeowner trapping. Homes near parks, green belts, or with compost setups should assume higher pressure and consider a professional perimeter inspection regardless of visible signs.
Prevention playbook

How to prevent norway rat in Metro Vancouver homes

  1. 1

    Seal every gap larger than a quarter

    A Norway rat can squeeze through any opening 13mm (½ inch) or larger — roughly the diameter of a Canadian quarter. Walk the perimeter and seal utility penetrations, dryer vents, weep holes, and gaps under siding with hardware cloth, steel wool, and weather-resistant sealant.

  2. 2

    Cut ground-level harbourage

    Remove woodpiles, ivy against the foundation, junk piles in side yards, and dense ornamental plantings within 24 inches of the house. Rats nest in harbourage within 30 metres of a food source — eliminating shelter is more effective than trapping symptoms.

  3. 3

    Lock down food sources

    Compost must be enclosed in a rodent-resistant bin (not open heaps). Bird feeders, pet-food bowls, and fallen fruit all sustain colonies. Store grass seed, pet kibble, and birdseed in metal or thick plastic containers — rats chew through thin plastic and cardboard.

  4. 4

    Install door sweeps + weatherstripping

    Garage doors, exterior doors, and crawlspace access hatches need tight-sealing sweeps. A rat-sized gap under a garage door is the single most common entry path on Metro Vancouver homes we service.

  5. 5

    Audit your roofline and vents

    Attic and roof vents, plumbing stacks, and chimney tops are high-probability rat entries on BC homes, especially post-1990 construction with cheaper vent hardware. Upgrade to galvanized hardware cloth bird-proofing on all roof vents; Norway rats climb and gain roof access via adjoining trees and wires.

  6. 6

    Know the SGAR rule (BC-specific)

    Second-generation anticoagulant rodenticides (bromadiolone, brodifacoum, difenacoum, difethialone) are restricted in BC as of 2023. Homeowners can legally use first-generation actives (warfarin, chlorophacinone) in tamper-resistant stations, but we recommend professional bait management — most homeowner mis-use kills non-target wildlife and teaches surviving rats bait-shyness.

The Wild Pest service

See our Norway Rat treatment page

Transparent pricing, 60-day return guarantee, same-day response across Metro Vancouver. Every treatment is documented with photos and service notes.

Frequently asked questions about norway rat

What's the difference between a Norway rat and a roof rat?+
Size and habitat. Norway rats (Rattus norvegicus) are heavier (200–500g), blunt-nosed, small-eared, and ground-dwelling — burrows, basements, crawlspaces. Roof rats (Rattus rattus) are lighter (150–250g), pointier-faced, larger-eared, and climbers — attics, soffits, rafters, mature tree canopy. Droppings are a quick field test: Norway droppings are blunt-ended olive pits; roof-rat droppings are pointed and slightly smaller. Metro Vancouver has both.
Are your methods SGAR-compliant under BC's 2023 ban?+
Yes. British Columbia's 2023 regulation banned general-use second-generation anticoagulant rodenticides (brodifacoum, bromadiolone, difenacoum, difethialone) because they secondarily poison owls, hawks, and domestic pets. Our Norway-rat protocol uses only approved first-generation anticoagulants in tamper-resistant stations plus snap traps. We can show you the active ingredients and Pest Management Regulatory Agency registration numbers on request.
Why do East Vancouver homes have more rats?+
Three overlapping drivers: pre-1985 housing stock with more entry points (our inspection data shows 38% of pre-1985 East Van homes have at least one active rodent entry vs. 11% for post-1995), dense urban infrastructure with abundant food sources, and proximity to Strathcona's established storm-sewer rat populations. The 2023–2024 construction churn across Mount Pleasant and central Burnaby dispersed established burrows, compounding pressure across East Van.
How do they get in? My home looks sealed.+
Norway rats can squeeze through any gap 12mm (half-inch) or wider and will gnaw to enlarge smaller ones. Common entry points: gaps at utility penetrations (gas, electrical, cable), garage-door corner seals, crawlspace vents with damaged mesh, soffit-fascia gaps at roof returns, and the base of exterior stairs where they meet the foundation. Our audit finds an average of 6 to 11 potential entry points per home.
How long does rodent treatment take?+
Most single-family Norway-rat issues resolve in 14 to 30 days with a proper trap-and-seal protocol. Severe infestations can take 45 to 60 days. The outcome you should expect is zero activity at day 30 and zero returns over the next 12 months — our 60-day guarantee covers that window, and recurring customers move to the quarterly plan for ongoing winter monitoring.
Can I use glue traps?+
We strongly recommend against them and never use them ourselves. Glue traps cause prolonged suffering, are considered inhumane by the BC SPCA, and frequently catch non-target species — songbirds, lizards, neighbourhood cats. Properly placed snap traps are faster, more humane, and more effective. Tamper-resistant bait stations are appropriate for homes without small children or pets with access to station placement areas.
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