Carpenter bee

Xylocopa sp.

Description:

Carpenter bees are large bees distributed worldwide. There are some 500 species of carpenter bee in 31 subgenera. Their name comes from the fact that nearly all species build their nests in burrows in dead wood, bamboo, or structural timbers. They use wood bits to form partitions between the cells in the nest. A few species bore holes in wood dwellings. Since the tunnels are near the surface, structural damage is generally minor or nonexistent. Carpenter bees can be important pollinators on open-faced flowers. Carpenter bees are traditionally considered solitary bees, though some species have simple social nests in which mothers and daughters may cohabit. However, even solitary species tend to be gregarious, and often several will nest near each other. It has been occasionally reported that when females cohabit, there may be a division of labor between them, where one female may spend most of her time as a guard within the nest, motionless and near the entrance, while another female spends most of her time foraging for provisions. Carpenter bees make nests by tunneling into wood, vibrating their bodies as they rasp their mandibles against the wood, each nest having a single entrance which may have many adjacent tunnels. There are two very different mating systems that appear to be common in carpenter bees, and often this can be determined simply by examining specimens of the males of any given species. Species in which the males have large eyes are characterized by a mating system where the males either search for females by patrolling, or by hovering and waiting for passing females, whom they then pursue. In the other type of mating system, the males often have very small heads, but there is a large, hypertrophied glandular reservoir in the mesosoma, which releases pheromones into the airstream behind the male while it flies or hovers. The pheromone advertises the presence of the male to females.