Osmia ribifloris, a native bee species developed as a commercially managed pollinator of highbush blueberry (Hymenoptera: Megachilidae)

Results of a field-trapping program for a native bee species, Osmia ribifloris biedermannii Michener, and the subsequent release of that population into a commercial plantation of highbush blueberry are presented. The 400 females reared from field traps produced 1461 cells after their release in a blueberry plantation. Nest holes of 6 mm in diameter were more attractive than 7 mm holes, cell provisions were composed exclusively of blueberry pollen-nectar resources, and immatures developed normally on those provisions. A unique non-sonicating method for collecting pollen from blueberry flowers is described; head and thoracic features adapted as "safe sites" for the transfer of pollen from flower to flower are also described; the average time spent at flowers and in flight between flowers is recorded; and, numbers of flowers visited/cell constructed is established. Data on nesting are used to calculate the potential nesting success of a population not exposed to pesticide treatments.