NATURAL PERSPECTIVES:Bee colonies in trouble

Vic and I were hiking on Huntington Mesa a few days ago when we noticed a loud hum coming from the swale. The willow trees growing there were in full flower, with pollen galore on the fuzzy willow catkins. The trees were positively alive with honeybees.

Bees are an important component of the natural ecosystem. They are also commercially important, even essential. Honeybees pollinate three-quarters of the world’s flowering plants, including 90 commercial crops. Plants that require bees for pollination include most of our food crops. Indeed, about one-third of our daily diet is bee-pollinated. With a world population of more than 6 billion people and rising, bees are essential for food production.

Honeybees aren’t native to North America. When European colonists first arrived in the 1600s, there were approximately 3,800 species of native bees. But the colonists brought domesticated Italian honeybees with them, and native pollinators went into decline.

Modern agriculture is dependent upon domestic honeybees, because there aren’t enough wild bees to do the job on the scale that is required by modern industrial farming. Giant agribusinesses have created huge stands of single crops. This type of monoculture farming requires large numbers of pollinators at exactly the right time and place, and this necess- itates massive long-distance movements of beehives.

In California, bees are needed right now to pollinate the almond trees that grow in the Central Valley, which produces 80% of the world’s almonds. California’s almond crop is the nation’s single-largest use of commercial honeybees, requiring 60% of the country’s commercial beehives from early February to mid-March. Semi-trailers full of beehives are driven to California each February to provide all of the bees that are necessary. And as more acres are planted in almonds, even more bees will be required to pollinate them.

These are really busy bees. After pollinating California’s almond crop, many commercial beehives are moved to other states to pollinate apples, cherries, melons, and finally cranberries in New England.

But all is not well in the world of bees. The Internet is abuzz with stories of massive die-offs of bee colonies. The mysterious new problem is called Colony Collapse Disorder. Symptoms of the disorder include a complete absence of adult bees in the colony and no dead bees in the hive or in the immediate vicinity. Larvae are present in the hive, but there are no adults to care for them. Bees fly away from the hive, never to return. In the course of previously known bee diseases, the hives are left full of dead bees.

To stay alive overnight, bees need the heat that is generated by all those little bodies packed together. A bee that is on its own at night will die. Researchers are looking into whether or not a new class of pesticides might be altering bee behavior and preventing them from returning to the hive.

During the late stages of collapse, only young adult bees are in the hives. Although a queen is present, there are not enough worker bees to care for the young. Oddly, the bees that are present do not consume the nectar and honey in the hive as they normally would. Beekeepers have also noted that honey in the hives stays untouched by other bees for two weeks after collapse of the colony, as though the hives were toxic. Usually other bees immediately colonize an empty hive and consume the food stores.

The cause of Colony Collapse Disorder is not known. Some speculate that it might be a contagious disease. Some think that it might be an immune disorder brought on by the stress of long-distance hauling and/or too many toxins in the environment, compounded by global climate change. Necropsies of affected bees have turned up a number of disease organisms all associated with stressed bee colonies, but a definitive causative factor has not been found.

Colony Collapse Disorder was first noticed in late 2006 in the Eastern United States. It has now been discovered in 22 states, including California.

For a variety of reasons, honeybees have been in decline for many years. Two years ago, 40% to 60% of the nation’s honeybees died, presumably from parasitic mites. Some bee experts are now saying that what was thought to be deaths from mites could have been unrecognized Colony Collapse Disorder. Some beekeepers have decided to get out of the business because of the difficulty of keeping the more aggressive Africanized bees. Rapid weather changes caused by global warming have killed bees as well. Problems have piled on top of each other to sting the industry hard. In 2005, for the first time since 1922, beekeepers had to import honeybees from outside North America.

Without bees to pollinate the trees, California’s $2 billion almond crop is at risk. Bees are also necessary to pollinate apples, peaches, pears, grapes, strawberries, squash, avocados, alfalfa and two-thirds of citrus trees. Between abnormal weather and bee deaths, California agriculture is in trouble. It’s too bad that wild bees can’t provide the level of pollination that is necessary for commercial agriculture, because those bees on Huntington Mesa sure looked healthy and busy.

You can protect the environment and yourself by not using pesticides at home and by buying organic foods.