by Grace Nichols
ALBANY, NY: Bees pollinate over 75 % of the world’s plants. The honeybee, A. mellifera is an introduced European honeybee and has been declining since the 1950’s. As of 2007, 29% of beekeepers reported a 75 % loss in their hives due to Colony Collapse Disorder which is thought to be caused by mites, disease, monoculture farms, and pesticides. A lot of concern about bees and pollination tends to focus on honeybees.
However, there are over 20,000 species of native wild bees, 3500 in the United States and 400 of them in New York State. These wild, native bees are generally solitary rather than social. They are better pollinators for many plants, and they will often pollinate crops in the absence of honeybees. They do not make honey but they are integral to an ancient food web and ecological balance.
The bee/ plant relationship can be specific: tomatoes want to be pollinated by bumblebees and alfalfa prefers other native bees.
Amanda Dillon, entomologist and field biologist, has been working with bees for 10 years. She spoke at the September Save the Pine Bush dinner, describing bees (the study of hymenoptera) and then her specific research in the Albany Pine Bush.
In general pollinators are in decline due to habitat loss and fragmentation, invasive species and pesticide use. Rusty-patched bumblebees were listed this year as federally endangered, even though they were ubiquitous not long ago. Their demise was a national wake-up call regarding the plight of bee species. Because of these declines, all states are required to come of up pollinator protection plans.
Native bees are solitary and do not make hives. The mother lays eggs with her ovipositor and buries them in the ground. She provides all paternal care. Her nest looks like a long tube in the ground with individual cells for each egg. She brings enough pollen into the nest for eggs to develop through their larval stages until they are ready to leave the nest.
The families of bees include Andrenidae (mining bees) — they are specialists who feed exclusivly on one plant. There are the Apidae – which include honeybees, carpenter bees, bumblebees and cuckoo bees, Colletide – the yellow-faced, plaster bees, the Halictidae – sweat bees, which are much smaller and Megachilidae – the leaf cutter bees, who cut circles of leaves to line their nests and carry pollen on their bellies. Other bees carry pollen in their corbicula, little pollen baskets on their hind legs. These bees are not aggressive. Honeybees, who are social bees, defend their hive and their Queen, and they will sting if they feel threatened, but the solitary bees are much less likely to do that.
Over the years the Pine Bush researchers have prioritized cataloguing the bee species that thrive out there. Often this requires microscope work to distinguish species. 131 bee species have found in the Pine Bush, establishing the importance of the habitat there in encouraging insect diversity. The Pine Bush Commission staff studied areas of intense conservation management.
The diversity of bees was quite high and over time, they found more sand specialists and pollen specialists in areas they had opened up. These bees thrived with the sunlight, the sand and the pollen bearing plants that grow where the thickets weren’t.
We are grateful that this protected wilderness exists to nourish species who are under threat in the industrialized world at large.
Amanda Dillon concluded that bees thrive under conditions of floral diversity, with an emphasis on native perennials whose nectar and pollen are more nutritious for them. 70% of native bees need nesting sites in open ground or in sand piles, so leaving open ground is important for them. 30% need logs or cavities and homeowners can install bee nests to encourage native bees in their yards. These can be wood blocks with holes drilled in them or tubular reeds, bundled together.
It is also important for bee-conscious gardeners to avoid plants and seeds contaminated with neonicotenoid pesticides to protect the diversity of bees and other insects.
Published in October/November 2017 Newsletter
Save the Pine Bush Newsletter