Identification
La guêpe cousine est une espèce forestière discrète qui joue un rôle de prédateur dans les écosystèmes boréaux.
A discreet forest species
Rare in urban settings, Vespula consobrina is mainly found in wooded and mountainous areas; its colony stays small and poses little threat.
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ADark colouring
Body mainly black with small pale-yellow spots on the abdomen; facial markings reduced compared with the other Vespula; identification is possible from the dominance of black.
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BBody
Modest size (8-11 mm); well-marked petiole; spindle-shaped abdomen; smooth stinger allowing repeated stings.
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CWings
Two pairs of transparent, slightly tinted wings; folded lengthwise along the abdomen at rest.
Worker
Handles food gathering, cell building and nest defence. Less aggressive than V. vulgaris or V. maculifrons away from the nest.
Life cycle
An annual cycle in boreal woodland habitatsThe overwintering queen emerges in May and chooses an underground cavity or a rotting stump in a forest setting to establish the nest.
Workers hatch from June onward and drive the expansion of the nest; the colony stays modest, rarely more than 200-300 individuals at its peak.
In August, the colony produces males and new queens; the mated queens leave the nest to find a winter shelter.
The nest is abandoned in autumn; workers and males die at the first frost; the mated queens overwinter under the forest litter.
Do not confuse it with
Its dark colouring sets it apart, but confusion with other Vespula is still possible.
Signs of activity
Underground forest nest
Nest built in an underground cavity, often among the roots of a stump or in an abandoned burrow in boreal or mixed forest.
Foraging activity
Workers gathering insects and sap on tree trunks along the edges of forest trails.
Discreet flight
Low, fast flight along trails; less conspicuous than other wasps; often confused with other dark hymenopterans.
This species is rarely a problem in a residential setting; it is mainly encountered during outdoor activities in the forest.
Treatment
Observation in the forest
- 1 Magnifying glass or macro photo Observe the reduced markings on the abdomen
- 1 Identification guide Confirm the species
- 1 iNaturalist app Submit a geolocated observation
- Photograph the wasp in profile to capture the reduced abdominal markings and the dominance of black.
- Compare it with photos of Vespula acadica and Vespula alascensis to confirm the identification by its dark colouring.
- Submit your observation to iNaturalist to help document the species in Quebec.
In the forest, watch out for hidden underground nests along the trails; a dull sound at ground level followed by intense activity is a sign of a nest nearby.
Identifying and locating in the wild
A detection method for forest trails
Look for a mostly black wasp with small pale-yellow spots; the low contrast sets it apart from the other Vespula.
Follow the workers' flight just above the ground in a forest setting; the entrance is often hidden by vegetation.
If the nest is away from marked trails, there is generally no reason to intervene; simply report it to the land managers.
Prevention
- Stay alert on the trails
When hiking, avoid walking off-trail in areas of dense vegetation where underground nests are more common.
Outdoors - Closed shoes in the forest
Wear closed shoes and covering clothing during forest activities to minimize the risk of an accidental sting.
Protection - Check before sitting down
Before setting down a bag or sitting on a stump or on the ground in the forest, visually inspect the ground around you for wasp activity.
Ground
Frequently asked questions
Is the blackjacket dangerous?
Like the other social wasps, it defends its nest and can sting several times; away from the nest it stays fairly unaggressive.
Where does it build its nest?
In a shrub, under an eave or in a cavity depending on conditions. The paper nest houses the colony from summer through autumn.
How do I recognize it?
A body striped yellow and black, a narrow waist and a darting flight; it is told apart from the furry honeybee and the bulky bumblebee.
What should I do about a nest that is in the way?
Do not disturb it in broad daylight. An exterminator comes in the evening to neutralize the colony safely.