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.[
These bees come in a variety of sizes although most are slightly larger than a honey bee. One of the most common species is the valley carpenter bee that is characterized by solid black females and golden males. They are as large as or larger than bumblebees.
Female and Male Valley Carpenter Bees.
As previous indicated these bees nest in wood. Their colonies consist of a series of tunnel-shaped burrows. As do other bees, carpenter bees collect pollen to feed to their young. Once collected, the pollen is formed into a ball about the size of a small marble. A single egg is then deposited on each ball, which subsequently is compartmentalized within the burrows (Figure 40). Their life cycle is completed in a few months as the larvae develop on the pollen balls.
A Tunnel of a Carpenter Bee with Developing Larva and Pupa. Image Courtesy Univar Corporation.
Carpenter bees are not true social insects as there is no division of labor, but many bees may occupy the same nesting burrow. The burrows typically are used year after year and can become rather extensive. Even though these are wood infesting insects, rarely do they do any significant damage to homes.
Occasionally they can be bothersome to the homeowner because the males are especially aggressive and will fly up to and buzz in a person’s face; however, they are totally harmless, as male Hymenoptera do not have stingers. The sting of the female is quite painful, but she is much less aggressive