Hymenoptera: Diseases, Parasites, and Pests

The decline in abundance and diversity of insects particularly social insects significantly impacts the ecosystem services most importantly pollination services.Other ecosystem functions impacted by this group of social insects that are crop pollinators, include nutrient cycle, food resources for animals and man and in bio-control of pests with some of the insects acting as parasitoids and parasites. The major sources of insect decline have been attributed to many biotic and abiotic stressors such as diseases, parasites and pests, habitat loss, alteration and fragmentation, pesticides, climate change, and invasive species. When social insects are simultaneously exposed to these multiple stressors, there are direct or indirect detrimental and negative interactive effects such as poor foraging and nutrition, suppression of immunity, and increase in disease susceptibility. In Social Hymenoptera, such as bees, ants, and wasps, the impact is more severe at both individual and colony levels because the insects are characterized by the presence of overlapping generations with cooperative social behavior. The litany of biotic stressors linked to the health of this insects are viruses, bacteria, fungi, protozoans, nematodes, mites, and pests.