Friday, March 19, 2010
Not exactly seasonal, but I wanted to show you this photo, sent to me by a friend, of Common Eastern Bumblebees (Bombus impatiens) mating last Fall.
The queen is the larger individual, clinging to the edge of a leaf, and the considerably smaller male is hanging below her.
By mid- to late summer, new virgin queen and male bumblebees are produced from successful colonies. These individuals leave the nest and seek each other out for purposes of reproduction.
Mate seeking in bumblebees was first recorded by Charles Darwin who set his children the task of following male bumblebees in his garden to record their behavior. The males of most species patrol a route which they mark with scent produced by their labial glands. The pheromone is deposited on "leaves, prominent stones, fence posts or tree trunks" according to Dave Goulson in his book, 'Bumblebees: Behaviour, Biology and Conservation'. It's not certain exactly how the newly emerged queen encounters the patrolling male. Presumably a combination of the species specific pheromone used for marking and the height above ground of the male's patrolling route provides the appropriate cue.
Observations are few, but presumably the male and female make contact in the air. Then, shortly after coupling, they alight until copulation is complete.
[Photo by Michelle Arsenault]