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ARS Home » Pacific West Area » Logan, Utah » Pollinating Insect-Biology, Management, Systematics Research » Research » Publications at this Location » Publication #261703
Title: Influence of rough handling on Osmia lignaria (Hymenoptera: Megachilidae) retention in commercial orchards

Author
item STANLEY, CORY - Utah State University
item Pitts Singer, Theresa
item BOSCH, JORI - Autonomous University Of Barcelona

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/11/2011
Publication Date: 6/1/2011
Citation: Stanley, C.A., Pitts Singer, T., Bosch, J. 2011. Influence of rough handling on Osmia lignaria (Hymenoptera: Megachilidae) retention in commercial orchards. Journal of Economic Entomology. 104:750-752.

Interpretive Summary: The cavity-nesting blue orchard bee (BOB) is a promising alternative pollinator for some fruit trees. Commercial BOB populations can be sustained in agricultural settings and have been known to increase fruit yield by two-fold or more each year. However, some females that are released for pollination do not end up nesting in commercially-provided nests. Bee dispersal from desired nesting sites has been repeatedly found to increase when BOBs in their cocoons were removed from their nests and allowed to emerge from their cocoons now kept in a container placed in orchards. In this study, we addressed the hypothesis that excessive or rough handling (due to the process of removing cocooned bees from their nests) of cocooned adult blue orchard bees results in a decreased number of females that establish nests at the site from which they emerged. We tested this hypothesis by severely shaking bees (as a proxy for rough handling) and subsequently monitoring nest establishment of shaken bees, as well as of unshaken bees. There was no significant difference in the number of shaken and unshaken females that nested. Results show that rough handling does not discourage nest establishment. These results are useful to BOB mass producers who desire to control diseases and parasites by removing healthy bees in their cocoons from their nests for winter storage.

Technical Abstract: The blue orchard bee, Osmia lignaria Say, is a promising alternative pollinator for some fruit trees. Commercial O. lignaria populations can be sustained in agricultural settings and have been known to increase fruit yield by two-fold or more each year. However, some females fail to establish at the provided nesting sites, which may be attributable to pre-nesting dispersal. Dispersal has been repeatedly found to increase when O. lignaria populations were placed in orchards as loose cocoons (extricated from their nests), which subjects pre-emergent bees to excessive handling. In this study, we addressed the hypothesis that excessive or rough handling of pre-emergent adult blue orchard bees results in a decreased number of females that establish nests at the site from which they emerged. We tested this hypothesis by severely shaking bees (as a proxy for rough handling) and subsequently monitoring nest establishment of shaken bees, as well as of unshaken bees. There was no significant difference in the number of shaken and unshaken females that nested. Results show that rough handling does not discourage nest establishment. These results are useful to O. lignaria mass producers who desire to control pathogens and parasites by removing healthy bees in their cocoons from their nests for winter storage.