• Larson, D. J.
  Department of Biology, Memorial University of Newfoundland
  
• Constantine, J.
  Department of Biology, Memorial University of Newfoundland
  
• McCarthy, M.
  Department of Biology, Memorial University of Newfoundland
  

The effect of aerial application of the insecticide aminocarb (MatacilR) on native pollinating insects was studied in a commercial forest region north of Gander, Newfoundland, during the summer of 1985. The study was conducted in four study blocks, two of which were unsprayed and used as control sites, and two which were given 2 applications of 70 gm aminocarb/ha in late June and early July.

An attempt to monitor the effects of the spray on bumble bee colonies in artificial domiciles was unsuccessful because bees did not colonize the nest boxes. Populations of ants, which did colonize the nest boxes, did not differ between control and spray areas. Bloom was surveyed in 4 sites in each of the study blocks. These data were used to develop indicies of bloom abundance (B.I.) which formed the basis for between area comparisons. Insect activity on bloom was monitored and used in a standardized form (numbers of bees/B.I., and numbers of non-bees/B.I.) for comparison of insect abundance between study areas. The standardized number of pollinators, their bloom use patterns, and seasonal changes in populations of pollinators were similar between control and spray areas. Thus, no impact of the aminocarb spray on insect pollinators was noted. Reasons for the apparent lack of effect of aminocarb on pollinating insects are discussed. Recommendations of spray application procedures that would minimize insecticide impacts on pollinating insects are included.