Usurpation: A Colony Taken Over by a Foreign Swarm.
Usurpation: After the spring nectar flow and swarming have passed, the weather conditions become hotter and drier as summer arrives. During this time, I watch for usurpation swarms. A usurpation swarm is usually a small summer swarm that occupies even a numerically strong queen-right colony. The mother queen of the colony is eliminated and replaced by the usurpation queen from the swarm. This bee behavior is relatively new to North American beekeeping.
Understand the ramifications of what occurs with this takeover. What appears like a small absconding swarm, destined to die, never to survive the winter, by the outdated “old rules” of bee biology, can now survive ― in “grand style” I might add. By taking over a large colony, the small usurpation swarm acquires its vast honey stores and combs.
It does not matter if numerous bees of the usurpation swarm are killed, fighting with bees of the large (host) colony. As long as the usurpation queen survives (and the mother queen dies), the genotype (genetics) of the colony changes to become the usurpation colony.
From my study of honey bees, the way I think about my bees has changed too. I have come to regard the summer as “usurpation season.” Usurpation activity varies in different summers, and apparently, not all summer swarms are usurpation swarms (a complication). Moreover, usurpation bees do not differ in body color or temperament from the gentle feral bees I trap in my bait hives from the woods in Piedmont Virginia.
Although I can be quite suspicious of a swarm as being a usurpation swarm, the only sure way I know a swarm is indeed a usurpation swarm is when I observe the bees usurp a colony, or I see recent evidence of a takeover (see below).