Carpenter Bee, common name for a group of mostly large, metallic-colored bees that construct nests in flower stalks or wood. There are about 730 species of carpenter bees. They live throughout the world wherever woody plants abound, especially in forested regions. Most species live in the tropics.
Carpenter bees resemble bumble bees but do not have yellow markings. The females of most species are black or blue with a metallic sheen and may be up to 2.5 cm (1 in) long. In general, the males look like the females. In some species, the males are covered by light brown, light green, or yellowish-green hairs. Carpenter bees typically fly long distances and visit many kinds of flowers. They can maintain their body temperature when the air is cool. Several species form colonies that display interesting social behaviors. Some of these species pass through several stages of social development as the colony matures.
When female carpenter bees construct tunnels in solid wood, their chewing of the wood can be heard from several feet away. Piles of sawdust beside the nest entrance and the presence of many bees in flight in the area provide clues that a nest is near. Brood cells (compartments for offspring) are constructed in the tunnels. The cells are separated by partitions made from sawdust or wood chips cemented together with saliva.
The females of the Virginia carpenter bee produce one generation each year, but individuals may live two years. Different generations of these bees have been known to occupy a nest for over 14 years. The hairy carpenter bee forms several communal nests in logs from a common nest entrance. A dominance hierarchy is established among the females, and a bee guards the entrance at all times.
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The mountain carpenter bee is found in western North America from Washington to Mexico. Females are entirely black. The males are black with whitish markings on the face, and they have gray fur on the thorax. Males and females are both larger than bumble bees. The species is mainly active at dawn and dusk during the summer and can be seen cruising around nectar-producing flowers, such as honeysuckles. The males chase each other and may fight. Mountain carpenter bees nest in Douglas fir or redwood timbers. Each nest tunnel measures 13 to 30 cm (5 to 12 in) long. Several bees inhabit the tunnel, which may be used year after year. Several nests may be constructed in the same timber and may weaken the structure.
The term carpenter bee is also used to refer to a number of other bees that burrow into wood or plant stems. In North America, these species are known as small carpenter bees. They are black or metallic greenish-black and measure 2 to 3 mm (0.1 to 0.2 in) in length.
Scientific classification: Carpenter bees comprise the genus Xylocopa in the family Anthophoridae of the order Hymenoptera. The Virginia carpenter bee is Xylocopa virginica, the hairy carpenter bee is X. pubescens, and the mountain carpenter bee is X. tabaniformis. Small carpenter bees are in the genus Ceratina, family Anthophoridae.