2010/10/15

The Case of the Missing Bees

The Case of the Missing Bees
Scientists say they have found an answer to the mystery of the disappearing honeybees
By Brenda Iasevoli

Where have all the honeybees gone? Over the past few years, millions of the helpful insects have disappeared. They fly away from their colonies in search of pollen and nectar and never return. Finally, scientists have solved part of the mystery. The two suspects in the disappearance are a fungus and a virus. (A fungus is an organism that feeds on matter; some fungi cause infection. A virus is a germ.) Bees infected with either the fungus or the virus separately could become sick, but they would probably survive. Bees infected with the fungus and the virus, however, would most certainly die, the scientists discovered.
"We found that the virus and the fungus together kill bees faster than anything that would happen alone," Colin Henderson told TFK. He is a member of the research team at the University of Montana that, together with Army scientists, made the discoveries.
In the past few years, bee populations in the U.S. have dropped 20% to 40%. The disappearance of entire beehives is called colony collapse disorder (CCD). Earlier studies focused on changes in weather and pesticides as possible causes of CCD. Pesticides are chemicals that are sprayed on crops to keep pests away.
Busy Bees
Why is CCD a growing concern? Honeybees do important jobs. They sip a sweet nectar from flowers and use it to make honey. They also pollinate flowering plants by carrying tiny grains of pollen from one part of a flower to another. The result: plants grow seeds and fruit. Bees pollinate crops that we eat every day including apples, almonds, broccoli, cucumbers and cantaloupe.
Each spring, beekeepers transport billions of honeybees around the country. They sell their pollination service to farmers. If there weren't enough bees to do the job, crops could suffer. About one-third of the food grown in the United States requires a honeybee to produce the seed or the fruit. There is no technology that can do the delicate work of bees. "In some seasons, there have been shortages of bees to pollinate all of the almond and citrus orchards," Henderson says.
Case Closed?
The discovery doesn't mean that bees are home free. Scientists are still doing research to discover how, exactly, the fungus and virus combine to kill the bees. For now, scientists advise beekeepers to treat the fungus, which is easier to cure than the virus, with a fungicide. This way, beekeepers can keep one half of the problem away and their colonies will be less vulnerable to attack.
"I hope no one goes away with the idea that we've actually solved the problem," Jeffrey Pettis of the U.S. Department of Agriculture. "We still have a great deal of research to do to resolve why bees are dying in the U.S. and elsewhere."
Max- Millions of bees are missing in the past few years. Bees are very important for our lives, even they sting us, because they pollinate the flowers, and they make honey, too. Less and less bees can cause a big problem, and it gets worse and worse after bees have gone. Scientists finally found the problem that what causes bees disappear. Bees die of fungus and viruses, because these two kinds of germs are very dangerous. Bees can survive with just one kind of germ, but since millions of bees are gone, I think those bees were being infected by both of these germs. We could not lose bees, because they are important to us, and can affect our lives. Without them, we can lose some kinds of foods that we could eat now, especially honey. And without bees, some people can be fired without feeding bees. But the bee problem is solved halfway, by treating the fungus with fungicide. This way can decrease half of been attacked colonies. And since fungus can be treated, that means the bees can have a bigger chance surviving. So we must count the bee population to make sure the bee problem is solved, and we can keep buying honey to eat.


沒有留言: