Swarms are normal behavior for bees, and if left alone, are usually quite safe. Put simply, a swarm is a collection of bees that have decided to look for a new home. They often stop at a location temporarily to rest and send out scouts to look for a suitable new residence.
A swarm can safely be recovered by knowledgeable beekeepers and then given a good home at an apiary.
If you observe a swarm, please contact Doris at 204-333-2135