Why species ID matters before you do anything
The five stinging wasp species in Metro Vancouver are not interchangeable. A paper wasp nest under your eaves is a moderate concern — if it's out of the way, you may leave it until fall without serious risk. The same size nest in the same location, if it turns out to be yellowjackets or bald-faced hornets, is a medical-emergency-waiting-to-happen. Treatment approaches also differ: paper wasp nests can be treated with direct aerosol contact; yellowjacket underground nests require dust application; wall-void nests of any species require a different wand-injection approach. Treating the wrong way for the species wastes money, risks injury, and usually fails to resolve the problem. Mud daubers, meanwhile, require no treatment at all — they're solitary, non-aggressive, and provide the ecological benefit of spider predation.
| Species | Size | Colour | Nest | Aggression | When to treat |
|---|---|---|---|---|---|
| Yellowjacket | 10-15 mm | Black + bright yellow | Underground or wall void | High when disturbed | Always — call pro |
| Paper wasp | 15-25 mm | Dark brown to black, sometimes red | Open-comb under eaves | Low | If near traffic — DIY possible early season |
| Bald-faced hornet | 18-25 mm | Black + white | Football-sized paper, in trees | Very high | Always — call pro |
| European hornet | 25-35 mm | Brown + yellow stripes | Hollow trees, large attic voids | Moderate | Call pro |
| Mud dauber | 15-25 mm | Black + thread-thin waist | Mud tube, solitary | Very low | Optional — scrape tube if desired |
Yellowjacket identification
Yellowjackets (Vespula spp. and Dolichovespula spp.) are the most common and most dangerous wasp species in Metro Vancouver. Visually: compact, robust body, 10-15 mm, strongly banded bright yellow and black with very little to no hair — smooth, waxy-looking in bright light. The waist (petiole) is visible but less pronounced than a paper wasp's. In flight, yellowjackets tuck their legs in — unlike paper wasps, which dangle their hind legs below the body. Behaviourally, the key yellowjacket signature is consistent directional traffic at a single entry point: a hole in the lawn, a crack in a foundation, a soffit gap. Workers fly in and out on a clearly defined path, often in numbers. The late-summer scavenger behaviour — hovering around outdoor food, entering open pop cans, harassing picnickers — is almost always yellowjackets, not paper wasps or hornets. This shift to food-scavenging happens in August when the colony's brood-rearing phase winds down and workers no longer have a food task inside the nest.
Paper wasp identification
Paper wasps (Polistes spp.) are the species most likely to be confused with yellowjackets by homeowners. Key visual differences: paper wasps are longer and slimmer, with a clearly defined thin waist (the petiole is pronounced and obvious), longer antennae, and notably longer hind legs that dangle below the body in flight. Colouration varies — most Metro Vancouver paper wasp species are brownish-red to dark brown with yellow markings, not the vivid yellow-and-black of yellowjackets. Size: 15-25 mm, noticeably larger than yellowjackets. The nest is the most reliable ID: the single open comb — hexagonal cells facing downward, hanging from a single stalk — is unmistakable. There is no outer paper envelope; you can see the cells directly. Paper wasp nests found under eaves, in outbuildings, or on porch railings are the most common non-emergency wasp call in Metro Vancouver.
Bald-faced hornet identification
Despite the common name, bald-faced hornets (Dolichovespula maculata) are a yellowjacket species, not a true hornet. They are the largest commonly encountered wasp in Metro Vancouver after European hornets. Visually: 18-25 mm, predominantly black with white (not yellow) facial markings, white bands on the abdomen, and white markings on the thorax. The combination of larger size and white markings makes them distinguishable from yellowjackets at a glance. Their nest is unmistakable: a large, rounded, grey paper structure with a smooth outer envelope — typically the size of a football by July, growing to rugby-ball or larger by August. Nests are commonly found hanging from tree branches, shrubs, or eaves at Metro Vancouver properties. Bald-faced hornets are the species most likely to aggressively pursue a disturbance beyond the nest — they will follow and continue stinging 10+ metres from the nest.
Mud dauber identification (and why you can leave them alone)
Mud daubers (Sceliphron caementarium and related species) are consistently misidentified as dangerous wasps by Metro Vancouver homeowners. They look alarming — large (15-25 mm), entirely black or black-and-yellow, with an extremely thin, elongated waist that looks almost like two body segments connected by a thread. But mud daubers are solitary wasps that do not have colonies to defend. They build the characteristic mud tube nests on exterior walls, under eaves, and inside sheds — each tube is a single egg cell containing a paralysed spider as larval food. There is no colony response if you approach the tube: the female that built it may return to check it, but she will not sting unless directly handled. We do not treat mud dauber nests at The Wild Pest unless the homeowner specifically requests cosmetic removal. They're free spider control.
Behavioural diagnostics
- Yellowjackets fly in straight, fast lines, often into a hole in the ground or a soffit. Consistent worker traffic at a single entry point is almost certainly a yellowjacket nest.
- Paper wasps hover and land deliberately on visible nests. They're slow flyers and rarely chase — easy to identify if you can see the open-comb nest.
- Bald-faced hornets are visible at distance because of size and white markings. Their nests are unmistakable — large grey paper structures hanging from branches or eaves.
- Mud daubers fly slowly with dangling legs, building distinctive mud tubes on walls. Solitary, not colonial — no nest defence to worry about.
- Late August food-scavenging (entering drinks, hovering over meat at BBQs): almost always yellowjackets. This behaviour is not seen in paper wasps or bald-faced hornets.
- Wasps inside the house: usually yellowjackets from a wall-void nest near an outlet or pipe penetration.