Bee nice to the bees. A bumblebee does its work on Fireweed in Alaska.

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bumblebee on fireweed

A bumble does its work on Fireweed in Alaska

Bees are the primary pollinators in ecosystems containing flowering plants. Bees and other insects pollinate 70 per cent of cultivated plants, accounting for 35 per cent of overall food production. Fewer bees means smaller harvests. Bees are in trouble; that means we are as well.

There are nearly 20,000 known species of bees. They are found on every continent except Antarctica, in every habitat on the planet that contains insect-pollinated flowering plants. Bees feeding on nectar and pollen, the former primarily as an energy source; the latter primarily for protein and other nutrients. Most pollen is used as food for larvae. The best-known bee species is the European honey bee, which, as its name suggests, produces honey, as do a few other types of bee.

Bees either focus on gathering nectar or on gathering pollen depending on demand, especially in social species. Bees gathering nectar may accomplish pollination, but bees that are deliberately gathering pollen are more efficient pollinators. It is estimated that one third of the human food supply depends on insect pollination, most of which is accomplished by bees, especially the domesticated European honey bee.

Bees have a long proboscis (a complex “tongue”) that enables them to obtain the nectar from flowers. They have antennae almost universally made up of 13 segments in males and 12 in females. Bees all have two pairs of wings, the hind pair being the smaller of the two; in a very few species, one gender or caste has relatively short wings that make flight difficult or impossible, but none are wingless.

Most bees are fuzzy and carry an electrostatic charge, which aids in the adherence of pollen. Female bees periodically stop foraging and groom themselves to pack the pollen into the scopa, which is on the legs in most bees, and on the ventral abdomen on others, and modified into specialized pollen baskets on the legs of honey bees and their relatives. Many bees are opportunistic foragers, and will gather pollen from a variety of plants, while others concentrate on only one or a few types of plant. A small number of plants produce nutritious floral oils rather than pollen, which are gathered and used by some bees.

Visiting flowers can be a dangerous occupation. Many assassin bugs and crab spiders hide in flowers to capture unwary bees. Other bees are lost to birds in flight. Insecticides used on blooming plants kill many bees, both by direct poisoning and by contamination of their food supply. A honey bee queen may lay 2000 eggs per day during spring buildup, but she also must lay 1000 to 1500 eggs per day during the foraging season, mostly to replace daily casualties, most of which are workers dying of old age.

Bees are in trouble; that means we are as well.

Colony collapse disorder (CCD) is a phenomenon in which worker bees from a beehive or European honey bee colony abruptly disappear. While such disappearances have occurred throughout the history of apiculture, and were known by various names (disappearing disease, spring dwindle, May disease, autumn collapse, and fall dwindle disease), the syndrome was renamed colony collapse disorder in late 2006 in conjunction with a drastic rise in the number of disappearances of Western honeybee colonies in North America. European beekeepers observed similar phenomena in Belgium, France, the Netherlands, Greece, Italy, Portugal, and Spain, and initial reports have also come in from Switzerland and Germany, albeit to a lesser degree while the Northern Ireland Assembly received reports of a decline greater than 50%.

The growth in the use of neonicotinoid pesticides has roughly tracked rising bee deaths since 2005. In 2012, several scientific studies showed that neonicotinoids had previously undetected routes of exposure affecting bees including through dust, pollen, and nectar; that very small amounts were sufficiently toxic to cause failure to return to the hive without immediate lethality, the primary symptom of CCD, and indicated environmental persistence of neonicotinoids in irrigation channels and soil. These studies prompted a formal 2013 peer review by the European Food Safety Authority that said neonicotinoids pose an unacceptably high risk to bees. CCD is probably compounded by a combination of factors. In 2007, some authorities attributed the problem to biotic factors such as Varroa mites, Nosema apis parasites, and Israel acute paralysis virus. Other contributing factors may include environmental change-related stress, malnutrition, and migratory beekeeping. Another study in 2012 also pointed to multiple causes, listing pesticides behind the varroa mite, genetics, habitat loss, and poor nutrition.

In April 2013, the European Union announced plans to restrict the use of certain pesticides to stop bee populations from declining further and by the end of the month passed legislation which banned the use of several neonicotinoids for the following two years. Shortages of bees in the US have increased the cost to farmers of renting them for pollination services by up to 20%

Since about 1972 there has been a dramatic reduction in the number of feral honey bees in the US – they have largely disappeared. And the number of colonies maintained by beekeepers has also declined. This decline includes the cumulative losses from all factors, such as urbanization, pesticide use, tracheal and Varroa mites, and commercial beekeepers’ retiring and going out of business. However, in late 2006 and early 2007 the rate of attrition reached new proportions, and the term colony collapse disorder was coined to describe the sudden disappearances. After several years of research and concern, a team of scientists headed by Jerry Bromenshenk published a paper in October 2010 saying that a new DNA-based virus, invertebrate iridescent virus or IIV6, and the fungus Nosema ceranae were found in every killed colony the group studied. In their study they found that neither agent alone seemed deadly, but a combination of the virus and Nosema ceraneae was always 100% fatal. Bromenshenk said it is not yet clear whether one condition weakens the bees enough to be finished off by the second, or whether they somehow compound the other’s destructive power. “They’re co-factors, that’s all we can say at the moment. They’re both present in all these collapsed colonies.”Investigations into the phenomenon had occurred amidst great concern over the nature and extent of the losses. In 2009 some reports from the US suggested that 1/3 of the honey bee colonies did not survive the winter, though normal winter losses are known to be around 25%. At the end of May 2012, the Swiss government reported that about half of the bee population had not survived the winter. The main cause of the decline was thought to be the parasite varroa.

Apart from colony collapse disorder, many of the losses outside the US have also been attributed to other causes. Pesticides used to treat seeds have been considered prime suspects.

Native pollinators include bumblebees and solitary bees, which often survive in refuges in wild areas away from agricultural spraying, but may still be poisoned in massive spray programs for mosquitoes, gypsy moths, or other insect pests. Although pesticide use remains a concern, the major problem for wild pollinator populations is the loss of the flower-rich habitat on which they depend for food. Throughout the northern hemisphere, the last 70 or so years have seen an intensification of agricultural systems, which has decreased the abundance and diversity of wild flowers.

What you can do to help:

You can help bees by planting bee-friendly flowers and shrubs in your garden or outside space. A garden or patch devoted to plants that are attractive to bees can be a source of great pleasure to any beekeeper, as much for the riot of color as for the activity of the bees.

Two other important factors contribute to a successful bee garden: The flowers should be in full sunlight and should be planted in groups. Flowers grown singularly or in twos and threes may fail to attract bees. A decent-sized clump of a suitable plant, such as lavender, is much more valuable. Likewise, bees often overlook flowers grown in shade even though they may produce nectar and pollen.

Unfortunately, some of the most spectacular-looking garden flowers are of no use whatsoever to the honeybee. Double-headed roses, chrysanthemums and dahlias, for example, provide no nectar and hardly any pollen. In contrast, many flowers that are often discounted as weeds, such as dandelions and forget-me-nots, provide a rich source of food. That is why one of the best and easiest things you can do to make your garden more bee-friendly is to throw away the weedkillers that maintain those immaculate-looking lawns and instead let your lawn and flower beds go wild.

If you are not quite ready to hand over your well-tended garden to the vagaries of nature, the next best thing is to leave just a patch to run wild. One way to get your wild garden started is to sow wildflower seed mixtures. The flowers will be a useful source of nectar and pollen.

Information drawn from multiple sources.

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