The benefit of bees
Forget
about honey, pollen and royal jelly. Just think of a world without beans,
tomatoes, onions and carrots, not to mention the hundreds of other vegetables,
oilseeds and fruits that are dependent upon bees for pollination. And
the livestock that are dependent upon bee-pollinated forage plants, such
as clover. No human activity or ingenuity could ever replace the work
of bees and yet it is largely taken for granted. It is often not realized
just how easy it is to help or hinder their effectiveness as crop pollinators
nor how much is lost by their loss.
To United States agriculture alone, the annual value of honey bee pollination can be counted in billions of dollars. Bees pollinate about one-sixth of the world's flowering plant species and some 400 of its agricultural plants. Poorly pollinated plants produce fewer, often misshapen, fruits and lower yields of seed with inevitable consequences upon quality, availability and price of food. One of the few farm activities that can actually increase yields, rather than simply protect existing yields from losses, is to manage bees to encourage good pollination. The destructive effects of the varroa mite (See varroa - a 'mitey' pest of bees), loss of wild bee nesting habitat, low world honey prices, Africanization of bees (see box) and the use of pesticides are making conservation of wild bees more important than ever.
Wild bees need long-lasting, undisturbed nesting sites in sunny, relatively bare patches of ground with a diversity of nectar and pollen-rich plants nearby. The greater the variety of flowering plants, the greater the number of bee species that will be attracted. One of the major risks, to both bee and plant diversity, is their separation through increasing fragmentation of wild uncultivated areas. Without bees, many flowering plants fail to set seed and without flowering plants, there is no food for bees. Leaving field margins, ditches, roadside verges and woodland edges unsprayed with chemicals, and undisturbed, does much for bee conservation.
By definition, chemical insecticides are harmful but individual products vary greatly in their toxicity to bees. Pesticides may kill quickly or, worse, kill slowly. If not immediately killed, bees can carry the contaminated pollen back to the colony where it enters the food chain and kills many more. An insecticide may be harmless to the health of the bees but may nevertheless inhibit pollination of the crop by acting as a repellent. Careful choice of pesticides may do much to reduce harm but farmers, especially in developing countries, may have few options and, on the whole, the more targeted the pesticide to the pest, the more expensive the product. Biological pesticides, however, are relatively safe to bees.
Timing of insecticide application is also critical. Many degrade after a few hours and spray applications in the late evening, when bees are inactive, reduces the risk that bees will be affected. Where bee keepers are hired by growers to bring hives to an orchard or field for pollination, crop protection must obviously be the subject of agreement between both parties, and never more so than where GM crops may be involved. (See box)
The use of bees for crop pollination is a huge subject (see In Print Crop Pollination by Bees). Different bee species behave differently and different crops have different pollination requirements. This is a tough time for farmers but it is also a tough time for beekeepers. Anything that can be done to enhance the pollination effectiveness of bees will be good for bees, beekeepers - and farmers.
