exploratory foraging flights and be attracted to visual and olfactory signals. Female mate-searching behavior might involve waiting for the male at the flower on which she discovers his markings or a directed flight toward a marked spot from a distance. Nesting All nesting cycles for all species of Xylocopa show common features. The bees have a period of reproductive dormancy even in the presence of the other sex that occurs during the dry seasons. Or, they may enter into a non-reproductive phase during the cooler months. The second characteristic of nesting cycles is that the dormant females are unmated. Additionally, mating occurs after territorial flights by the males and before nest establishment. The name "carpenter" comes from the fact that these bees excavate nests inside a variety of woods, and the species' common name refers to the Californian Central Valley in which they are commonly found. Like its relative, Xylocopa virginica, X. sonorina like to nest in fence posts, telephone poles. and structural timbers. The bees will tunnel through wood with their mandibles, although they do not ingest the wood in the process, and they avoid painted or stained wood. The tunnels average in length and consist of a linear series of partitioned brood cells. The adult bees spend the winter in the tunnels. Most nests of X. sonorina contain a single female and her brood. Because Xylocopa species are not aggressive, defense is primarily carried out by building well constructed cell partitions, blocking the nest entrance in various ways, covering the cell partitions with liquid substances, or sacrificing all the brood of a nest that has been compromised by a parasite. Entomologist Julian R. Yates III of the University of Hawaii at Manoa describes the life cycle of X. sonorina in Hawaii: Having located a suitable piece of wood, the female bee begins to excavate a single tunnel in preparation for egg laying. Because of our tropical climate, egg laying by female carpenter bees occurs year-round although it may decline during the winter months, when the weather is worse. Before laying eggs, the female collects pollen and deposits it, in the form of a ball, in the tunnel at a point furthest from the entrance. She lays a single egg on the pollen ball and seals both in a chamber with wood shavings. She may lay several eggs, each on its own pollen ball and inside its own sealed