You have found a bee swarm — what now?

A dense, humming ball of insects on a branch or under the roof overhang looks threatening — but in most cases it is a swarm of honey bees looking for a new nesting site. Once correctly identified, it is neither dangerous nor a case for wasp control.

What a bee swarm actually is

When a colony swarms, the old queen leaves the hive together with a large part of the workers in order to found a new colony elsewhere. The swarm often rests for a few hours or a couple of days on a branch, a fence or a house wall while scout bees search for a suitable cavity. Since the bees have neither brood nor honey to defend, they are unusually peaceful during this phase.

What you should do now

Stay calm and keep your distance — do not touch the swarm, spray it with water or try to drive it away with smoke. Contact a beekeeping association in your region instead; many cantons also run swarm reporting points that put you in touch with volunteer beekeepers. They will collect the swarm properly in a box and move it into a new hive, where it lives on as a full colony.

Why biocides against bees are prohibited

In Switzerland the honey bee is considered a farm animal and is the most important pollinator of our crops and wild plants. Using insecticides or other biocides against bee colonies is therefore prohibited, regardless of whether the swarm is hanging in the open or has already settled in a cavity such as a roller shutter box. Even a colony that has already established itself after swarming should be documented and reported to a beekeeper rather than destroyed.

Avoiding confusion with wasps

Because the sheer number of insects makes a bee swarm unsettling to look at, it is occasionally mistaken for a wasp nest. You can tell them apart by their hairiness, body shape and behaviour — more on this in our guide «Wasp or bee? The quick comparison». You will also find an overview of all native species at /arten and in our pillar guide «Identifying Switzerland’s wasp species».