Professor: Until recently, we knew almost nothing about how important bees are in maintaining natural diversity. Now we know more about them. We know, for example, that bees fall into two categories: wild bees and domesticated honeybees. A main reason for the domestication of bees has always been the production of honey and beeswax. We also know that honeybees are the dominant pollinators. In addition to bees, wasps, moths, butterflies, flies and beetles , as many as 1,500 species of birds and mammals serve as pollinators. Many crops of commercial importance such as almond, cherry, avocado pear, watermelon , cucumber, rely on pollination by insects, and of these insects, bees are by far the most important. Animals and insects provide pollination services for over three-quarters of the staple crop plants and for 80% of all flowering plants in the world. The economic value of animal pollination to world agriculture has been estimated to be 200 billion US dollars per year. Pollination is one of nature’s services to farmers. So think about this: if you eliminated the pollinators, it would take the food right out of our mouths. We biologists never imagined we’d see the day when wild plants or crops suffered from pollinator scarcity. But, unfortunately, that day has come. In fact, farmers in Mexico and the U.S. are suffering the worst pollinator crisis in history. So… what happened? Any ideas? Alicia?
Alicia: Is it…um… because of natural enemies? I read something about a kind of parasite that’s killed lots of bees.
Professor: It’s true. An outbreak of parasitic mites has caused a steep decline in North American populations of honeybees. But parasites aren’t the only factor.
Alicia: What about the pesticides used on farms? All those chemicals must have an effect.
Professor: Most definitely, yes. Pesticides are a major factor. Both wild and domesticated bees are in serious trouble because of pesticides. In California, farm chemicals are killing around 10% of all the honeybee colonies. Agriculture in general is part of the problem. Another example is the monarch butterfly. Millions of monarchs from all over the U.S. and southern Canada fly south every year in late summer. The monarch is the only butterfly that returns to a specific site year after year. Unfortunately, the herbicides used in their milkweed in the Great Plains are taking a toll on monarchs, and fewer of them are reaching their winter grounds in Mexico. In a recent field study at Cornell University in the U.S., it was found that monarch butterfly caterpillars eating com toxic pollen blown on to milkweed plants near com fields had suffered significant adverse effects leading to death of nearly 20% of the caterpillars.
Alicia: Wow, 20%, thats so tragic!
Professor: And it’s more than that. There are over 1,500 species of butterflies in the Indian subcontinent, but their population is dwindling because of environmental changes. Many manmade environmental changes like deforestation, extension of farming and unrestricted urbanization are threatening some species of butterflies to extinction by destruction or disturbance of their larval as well as adult food plants, feeding grounds and shelters. Many of the most spectacular and endangered species have various levels of protection under local legislation. However, there is a major trade in the spectacular tropical species for incorporation in ornaments and souvenirs. The international demand for insects is greater than most people realize.
Alicia: Yes, indeed. I once read an article about another important pollinator – the long-nosed bat. These amazing animals feed on cactus flowers. But they are having a tough time, too. Some desert ranchers mistake them for vampire bats, and they’ve tried to poison them, or dynamite the caves where they roost.
Professor: Yes, we must recognize that pollination is not a free service, and that investment and stewardship are required to protect and sustain it, so what can be done about this situation?
Alicia: Well, wildlife farming, you know, based on sustainable exploiting wild creatures, can help to save endangered species like butterflies and their habitats. Besides, gardeners, orchard growers, farmers and urban dwellers can switch to more pollinator-friendly organic methods of cultivation to reduce wildlife exposures to insecticides, herbicides and fungicides.
Professor: That’s rightl Actually, the focus of beekeeping needs to change from conventional honey production to crop pollination.