Pollinators contribute greatly to food security. Effective pollination results in increased crop production, commodity quality and greater seed production. Many fruits, vegetables, edible oil crops, stimulant crops and nuts are highly dependent on bee pollination. Even where honey bees or bumble bees are used to pollinate high value crops, concurrence of native bees, both social and solitary species, increases yield and quality of those crops. A serious threat to this essential pollination service is the increasing evidence of a global decline in insect pollinators, both native and managed. Various causes for this decline have been identified, including loss, destruction and degradation of habitats; reduced genetic diversity of nectar plants; pests and pathogens; competition by introduced pollinators; climate change; and pesticide use – all individually or in concert, potentially causing direct and indirect adverse effects on pollinator populations.