Dynamic of Nest Foundation by Solitary Bees and Wasps (Hymenoptera, Aculeta) in an area of the semiarid caatinga, Northeastern Brazil

Abstract

The dynamic of nest foundation by solitary bees and wasps was evaluated by means of trap-nests at Estação Ecológica do Seridó, Serra Negra do Norte municipality, Rio Grande do Norte State, in the semi-arid region of Northeastern Brazil. Ten wooden blocks were used, each one with 32 openings, placed 1.5 m above ground. Cardboard trap-nests with 4, 6, 9 and 12 mm of diameter were placed, and inspected every 15 days. The blocks were installed in contrasting conditions in this semiarid region; (i) a drier locality, without water storage, even nearby, and (ii) near water bodies, with available water even during the dry season. The number of nests of bees and wasps collected during the dry seasons were lower than that during the rainy season. During the dry seasons bee´s nesting were restricted to places near water bodies, what was interpreted as evidence of spatial variation in its reproductive activities.