The Xylocopa violacea, commonly known as the violet carpenter bee, is one of the largest bees found across Europe and parts of Asia. Often seen buzzing through gardens and sunlit woodlands, its size and distinct sound make it a noticeable presence. This insect belongs to the Apidae family, which includes honey bees and bumblebees. As a solitary bee, its behaviors and life cycle differ from its hive-dwelling relatives, centering on the woodworking skills that give it its name.
Identifying the Violet Carpenter Bee
The most defining feature of the violet carpenter bee is its size and coloration. Adults can reach up to 2.5 centimeters in length, with a body that is almost entirely a glossy, shiny black. This sheen helps distinguish it from the more densely-furred, often matte-colored bumblebees. The bee’s wings are what give it the “violet” part of its name, displaying a metallic, blue-violet luster when they catch the sunlight.
This bee’s appearance is complemented by the deep, low-pitched buzzing sound it produces in flight, which is often heard before the bee is seen. While its body shape is robust and similar to that of a bumblebee, the violet carpenter bee’s abdomen is noticeably less hairy, contributing to its shiny appearance.
Nesting Habits and Habitat
The common name “carpenter bee” references the species’ method for creating nests. Unlike social bees that build wax colonies, the female Xylocopa violacea is a solitary woodworker. She uses her powerful mandibles to excavate tunnels into dead wood, such as old tree stumps or fallen logs. These tunnels can reach up to 30 centimeters in length.
Within these galleries, the female constructs a series of individual brood cells. She uses chewed wood fragments mixed with saliva to build partitions, separating each cell from the next. Each partition measures about 2 millimeters thick in the center and becomes thicker at the edges. This solitary female is responsible for the entire nesting process.
These bees prefer sunny, warm habitats with access to flowering plants and suitable wood for nesting. This brings them into human-managed landscapes like gardens, parks, and orchards. They do not attack living trees and prefer untreated, weathered timber, but may nest in structural timbers of buildings or fences. Their geographic range extends from Europe to Central Asia.
Life Cycle and Ecological Importance
After constructing a brood cell, the female provisions it with a mixture of pollen and nectar, often called “bee bread,” which will serve as food for a single larva. She then lays one egg on this food source and seals the cell before starting the next one. A single tunnel may contain up to 15 of these sealed cells.
The larvae hatch and consume their provisions, growing within the protection of the wooden cell. They eventually pupate and transform into adults. These new adult bees typically hibernate within the nest during the winter and emerge the following spring, around April or May. The adults then seek mates, and females search for suitable wood to excavate their own nests.
As pollinators, violet carpenter bees are highly effective. Their large bodies allow them to carry significant amounts of pollen, and they visit a wide variety of plants, including those with complex or deep structures. Though females have a stinger and can use it if provoked, they are not aggressive. Males, which lack a stinger entirely, are harmless.