Pollinators are vital to the health of natural food chains and the functioning of ecosystems. They are also often the key to success in agriculture. Through foraging and natural movements pollinators transfer pollen - allowing the fertilization and subsequent fruiting of trees and plants. Pollinators can be invertebrates such as bees, butterflies and beetles or they can be vertebrates like bats and birds. Of all flowering plants, 85% require an animal (mostly insects) to transfer pollen for fertilization.
Pollinators account for the fertilization of 35% of crop production worldwide with a value of $217 billion annually. Both European honeybees and 3500+ species of native bees account for the majority of agricultural pollination. Their bodies are designed to attract the electrostatically charged pollen with their bristly thorax and hairy ‘pollen baskets’ on their legs. Honeybees forage differently than native bees so that when both are present, crop set is often doubled.
Since the 1950s there has been a 50% decline in managed honeybee hives. Wild hives have fared even worse. Almost 17% of vertebrate pollinators and over 40% of invertebrate pollinators are facing the threat of extinction. Over 140 species of butterflies in North America are at risk while monarch butterflies alone have declined by 90% in only two decades.
Why is this happening?
Pesticide Exposure: Heavy pesticide use in agriculture and landscaping shows direct correlation to declines in all insects, especially bees. The synergistic effects of pesticides are not well understood and the application of different pesticides on the same property may intensify toxicity to pollinators.
Changes in land use: Natural habitats and open space are being lost to development. In the last eight years, over 8 million acres of former farmland and natural space has been paved or developed. Urbanization reduces nesting habitat for bees and limits the floral resources they require for food.
Invasive species: As foreign species of plants, insects, fungi and bacteria become introduced, they alter and interfere with the proper functioning of ecosystems by pushing out native species, changing the availability of food resources, and introducing diseases for which endemic species have no defense. Pathogens, Parasites and Disease: Honeybees have been hard hit hard by diseases and varroa mite infestations. Colony collapse disorder has impacted bees world wide, the causes are still being investigated.
Climate Change: Weather patterns are becoming more extreme, growing seasons are altering and average temperatures are warming. For pollinators, climate change affects food sources that may not be available at times when they are expected and needed.
Changes in agricultural methods: Bees need a diversity of plants that flower throughout the growing season. Small farms and gardens that supplied diverse crops are in steep decline. This has resulted in reduced nutrition for bees and consequently less resistance to disease. They are also less likely to bounce back from environmental crises (drought, floods etc.) The loss of field borders and scrubland also means less habitat for native bees.