Page Banner

United States Department of Agriculture

Agricultural Research Service

Related Topics

Research Project: Assessing Impact of Fungicides on Osmia Lignaria, the Blue Orchard Bee, and Determining Impact of Bee Nesting Site Placement on Almond Yield

Location: Pollinating Insects-- Biology, Management and Systematics Research

2013 Annual Report


1a.Objectives (from AD-416):
Determine if and which fungicides cause lethal of sublethal effects on blue orchard bees in field, caged, and laboratory studies. Also assess almond nut yield according to placement of blue orchard bee nesting sites within commercial orchards.


1b.Approach (from AD-416):
Work will be performed during early spring in large (>100 acre) trials and commercial almond orchards in California over five years. Visual observations of blue orchard bee adults at nesting sites before and after fungicide sprays will determine if and how the fungicides change bee foraging or nesting behavior. In nest observations of immature bees will determine if fungicides inhibit development or kill larvae. Chemical analyses of mass provisions will determine if bee food is contaminated with fungicides. Cage studies will all for testing specific fungicides and their surfactants or other mixed products in order to define how and what components are deemed detrimental to bee reproduction, longevity, or survival. Further screening for effects of fungicides on behaviors related to learning and memory will be performed in the laboratory. Additionally, nest occupancy by bees according to nesting site placement will be matched with yield of nuts at various distances from nesting sites throughout the orchards. Analyses will reveal effects of the distribution of nesting bees on nut yield.


3.Progress Report:

In FY 2011; we performed a study in field cages at Paramount Farming Co. to determine if fungicides had a sublethal effect on Osmia lignaria using visual observations and video recordings. Data obtained from personal and video was analyzed in 2012. A companion study on M. rotundata was performed in summer 2012. Data from visual observations and video recordings of M. rotundata are being analyzed just as for O. lignaria. A scientific report will be made on the fungicide effects on both solitary bee species.


Last Modified: 12/19/2014
Footer Content Back to Top of Page