ENHANCED BERM HABITATS INCREASES THE ABUNDANCE OF NATURAL ENEMIES OF INSECT PESTS AND POLLINATORS IN THE HOLLAND MARSH, ONTARIO

Abstract

The Holland Marsh (HM), Ontario, is an agroecosystem with a primary focus on carrot and onion production. It contains negligible uncultivated habitat to support beneficial insect populations. Upgrades to the HM drainage system have provided an opportunity to investigate how enhancements to canal berms can affect natural enemies of insect pest populations and pollinators. Five berm sites were established, each with three treatments: (1) unmanaged control; (2) a floral enhancement; and (3) a floral + shrub enhancement. These sites were monitored over two years using both active and passive trapping. Enhanced berm sites did not offer refugia for primary insect pests, and positively affected the abundance of some natural enemies and insect pollinator groups. Future research should examine: the efficacy of natural enemies in reducing primary insect pest population; and, the relative floral attractiveness of planted floral treatments to bee species to better understand how management strategies can support threatened non-Apis bees.