Project Number: 5428-21000-013-28
Project Type: Nonfunded Cooperative Agreement

Start Date: Apr 01, 2011
End Date: Mar 31, 2016

Objective:
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.

Approach:
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.