| Trait | Norway rat | Roof rat |
|---|---|---|
| Body size | 20-25 cm | 16-20 cm |
| Tail vs body | Shorter than body | Longer than body |
| Snout | Blunt | Pointed |
| Eyes / ears | Smaller eyes, smaller ears | Larger eyes, larger ears |
| Weight (adult) | 350-500 g | 150-250 g |
| Activity | Ground level, burrowing | Climbing, arboreal |
| Common Metro Van areas | Richmond, Strathcona, agricultural-adjacent Surrey, dike-edge Pitt Meadows | Vancouver west-side, Burnaby Heights, North Van, Steveston |
| Droppings | 18-20 mm, blunt, capsule | 12-15 mm, curved, pointed both ends |
Why getting the species right matters
If you treat roof rats with a Norway rat protocol — bait stations along the foundation, traps in the basement — you'll have nothing to show for the work because the rats are operating overhead. The pest is wasted bait, frustrated homeowner, and the colony continues breeding in the attic. The reverse failure is rarer but happens: setting attic traps for what turns out to be Norway rats nesting under the deck. The first two minutes of any rodent inspection are species ID for exactly this reason.
Range expansion notes
Roof rats were historically associated with the southern US and tropical climates. Their range has expanded north over the past 30 years, partly driven by mild winters and continuous urban cover. Vancouver's west-side has had established roof rat populations since the early 2000s; North Vancouver and West Vancouver since around 2010. Burnaby Heights and parts of New West are now consistently roof-rat-dominated. Norway rats remain the dominant species in the Fraser delta lowlands (Richmond, Pitt Meadows, agricultural Surrey) and along waterways.
Frequently asked questions
Can I have both species at once?+
Are roof rats worse than Norway rats?+
Why are roof rats showing up in newer Vancouver homes?+
Treatment protocols compared: the full difference
| Protocol element | Norway rat | Roof rat |
|---|---|---|
| Primary inspection zone | Foundation, crawlspace, ground-level perimeter | Roof line, soffit-fascia, gable vents, attic |
| Bait station placement | Exterior perimeter at foundation level, 6-10 m spacing | Attic only (tamper-resistant), exterior only if ground activity present |
| Trap placement | Ground-level indoors — garage, basement, under appliances | Attic along joists and beams; roof-rat runway paths |
| Exclusion priority | Crawlspace vents, slab gaps, deck junctions, sewer cleanout | Soffit-fascia, gable vents, roof returns, dormer junctions |
| Tree management | Not required unless arboreally adjacent structure | Essential — trim all branches within 1 m of roofline |
| Monitoring timeline | 4-6 weeks typical to zero activity | 6-8 weeks — longer due to canopy population replenishment |
| Attic insulation risk | Low (Norway rats rarely nest in attics) | High — insulation contamination common after 3+ months |
How Metro Van's geography shapes species distribution
Norway rats dominate the Fraser delta lowlands for a reason: they evolved as commensal species following river systems and agricultural land. The Richmond and Pitt Meadows dyke system provides ideal Norway rat habitat — soft soil for burrowing, water adjacency, continuous agricultural food supply. Roof rats dominate the forested North Shore and Vancouver west-side for different reasons: mature arboreal cover provides the canopy connectivity their climbing behaviour exploits, and mild wet winters create the same conditions as the subtropical origins where the species first established in BC. The boundary isn't sharp — the Strathcona and Commercial Drive areas have both species because they sit between agricultural/waterway character and tree-covered heritage housing. When both are present, the inspection and treatment must address both levels independently.
For property managers and strata councils, knowing the species matters for budgeting. Norway rat programmes are typically exterior bait-station maintenance contracts with quarterly service. Roof rat programmes require annual roof inspections, attic trap placement and retrieval, and canopy management coordination. The budgets are different, the liability exposures are different (attic insulation damage vs foundation undermining), and the contractor skill set needed is different. Specifying the right programme requires confirming the species first — which is exactly why every Wild Pest booking starts with a species-ID inspection rather than a pre-packaged protocol.