Individual study: San Rafael Desert bee Osmia sanrafaelae numbers increase four-fold in one year when reared in a cage; field studies near Clarkston, Utah, USA
Parker F.D. (1985) A candidate legume pollinator, Osmia sanrafaelae Parker (Hymenoptera: Megachilidae). Journal of Apicultural Research, 24, 132-136
Some leafcutter bee species (family Megachilidae) are declining or threatened, and captive rearing may be one strategy to augment or re-establish populations. Osmia sanrafaelae is known only from the deserts of southern Utah. This study reared O. sanrafaelae in a cage on an alfalfa field near Clarkston, Utah, USA, to see if populations could be managed or augmented.
On 7 July 1983, 50 male and 50 female adult O. sanrafaelae bees were released in a 6 x 6 x 2 m cage made of saran cloth, erected over a crop of alfalfa Medicago sativa before flowering. Several potted evening primrose plants Oenothera hookeri were put in the cage for nesting material. An unspecified number of pine nest boxes were attached to a board and placed near the top of the cage on the west side, facing east. Boxes were 15 cm3, each with 49 9-mm holes drilled and lined with waxed paper drinking straws.
83 nests were built in the cage, containing 1,148 cells in total. Each female bee in the cage produced an average of 23.1 cells and 1.6 nests.