Identification
Les bourdons nichent dans des cavités existantes: terriers abandonnes, sous les galeries, dans l'isolation. Généralement peu agressifs, ils ne piquent que si le nid est directement menace. La colonie disparaît naturellement chaque automne.
A pollinator worth protecting
If the nest is not in a dangerous spot, consider tolerating it until autumn, when the colony dies off naturally. Bumblebees are essential pollinators for gardens and crops.
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AFurry body
Body covered in dense yellow and black hairs for thermoregulation and pollen transport
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BCorbiculae
Pollen baskets on the hind legs, visible as yellow balls during foraging flights
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CSmooth stinger
A barbless stinger that allows multiple stings. Used only as a last resort to defend the nest
Queen
Overwinters alone and founds the colony in spring. Builds the initial nest, lays the first eggs, and broods the larvae.
Worker
Gathers nectar and pollen. Characteristic slow, humming flight. Not very aggressive unless the nest is directly threatened.
Male
Has no stinger. Appears in late summer to mate with the new queens. Dies after mating.
Life cycle
Holometabolous · 4 stages · annual colonyThe queen lays eggs in wax cells built inside the cavity chosen as the nest
The larvae are fed pollen and honey in their individual wax cells
Complete metamorphosis inside the capped cell over about 2 weeks
The colony reaches 100 to 400 individuals at its peak in August, then dies off naturally in autumn
Confusion with wasps
Bumblebees are often confused with other stinging insects.
Signs of activity
Coming and going at ground level
Bumblebees entering and leaving a hole in the ground, under a shed, or in a wall cavity, flying slowly with a humming sound
Low, humming flight
Characteristic slow, low flight, slower and louder than a wasp's. A distinctive humming sound as they pass by
Visible pollen baskets
Bumblebees with visible yellow pollen balls on their hind legs, a sign of an active colony nearby
By late summer the colony is at its peak and bumblebees become more defensive. But the colony disappears naturally in autumn without any intervention needed.
Treatment
Nest management
- 1 Insecticide powder Applied at the nest entrance at nightfall for a gradual effect on the colony
- 1 Protective equipment Coveralls, gloves, and a veil are mandatory for any intervention on the nest
- Assess whether the nest truly poses a risk. If intervention is necessary, act at nightfall when the bumblebees are inside the nest. Apply the insecticide powder at the entrance without blocking it.
- After 5 to 7 days, check that activity has stopped. Remove the nest and fill in the hole to prevent reuse by a new queen the following spring.
The colony dies off naturally in autumn. If the nest is in a spot that is not a problem, patience is the most ecological and least risky option.
If you are not sure of the species (bumblebee vs. honeybee), contact a beekeeper. They can retrieve a honeybee swarm free of charge.
Bumblebees sting only if the nest is directly threatened. Walking past at a distance without sudden movements usually allows for coexistence without incident.
Locating the nest
Confirm the species and its position before intervening
Slow, humming flight with a furry body = bumblebee. Fast, jittery flight with a smooth body = wasp. Important to check before treatment
Follow the flight paths to locate the entrance. Bumblebees use rodent burrows, spaces under sheds, or insulation cavities
Is the nest really a problem, or can it be tolerated until autumn? Assess the real risk before taking any action
Prevention
- Fill in burrows in autumn
After the colony dies off naturally in autumn, fill in holes in the ground and under sheds to prevent reuse the following spring.
Garden - Protect accessible insulation
Accessible mineral insulation spaces are attractive to queens looking for a nesting site. Seal outdoor access points before spring.
Foundation - Rodent control
Eliminate rodents that create the burrows bumblebees use. A rodent prevention program also reduces bumblebee nests.
Garden - Install bumblebee houses
Place bumblebee houses away from the building to attract queens to a preferable site. Bumblebees stay in the garden as pollinators.
Garden
Frequently asked questions
Is the bumblebee dangerous?
The bumblebee (Bombus) is peaceful and rarely stings; only the female has a stinger and uses it only if threatened. It is above all a valuable pollinator.
Should a bumblebee nest be destroyed?
Usually not: the colony is small and dies off naturally in autumn. If the nest is in a high-traffic spot, a professional can relocate or neutralize it.
How do I tell a bumblebee apart from a honeybee and a wasp?
The bumblebee is large, round, and very hairy, striped yellow and black; the honeybee is smaller and slimmer, the wasp smooth and slender with a marked waist. The bumblebee flies heavily.
What should I do about a bumblebee nest near the house?
Keep your distance and avoid blocking their flight path. If action is needed near a walkway, an exterminator can remove or neutralize the nest safely.