May 29--When you see a bee, do you flinch? Or do you marvel at one of nature's most ingenious and valuable creatures?
The bees that buzz past, unless distracted by your picnic, are on their way to nearby flowers for lunch, picking up pollen for protein and nectar for carbs.
As bees travel, they run a crucial food errand for us, too: while rummaging through the flowers, bees collect grains of pollen from male blossoms and leave flecks behind as they visit female blossoms, triggering fertilization. About one-third of our crops depend on the bees, mainly commercially managed honeybees, for pollination. No pollen distributed by bees? No apples, no cherries, no squash, no pumpkins, no alfalfa -- it's an amazingly long list.
The problem: The bees do not seem as content in their work as they should be.
For about five years, starting in late 2006, honeybee keepers reported the startling loss of complete hives, a condition known as Colony Collapse Disorder: The worker bees would disappear en masse, leaving behind a queen, plenty of food and a mystery.
That phenomenon abated, but bees in the hive keep dying. Winter losses are higher than what beekeepers call "economically acceptable." More baffling is how losses spread to the summer months. Over the past year, more honeybees died during summer than winter for the first time, according to a U.S. Agriculture Department survey of managed honeybee colonies.
Something is wrong, the bees are telling us, but there is no obvious cause, no bee plague. Instead, many experts see a confluence of stresses that may be taking a toll on bee health. The list of suspected culprits includes:
A virus-carrying mite that attacks honeybees.
Declining habitat where bees forage.
Climate change.
Pesticide poisoning.
Worry about pesticides gets much of the attention, especially a class known as neonicotinoids that was introduced in the 1990s. Neonicotinoids are absorbed into the crops or landscape plants they are supposed to protect, which means the pollen and nectar can be toxic to bees as well as targeted insects.
Some environmentalists are certain neonicotinoids are the culprit, but the science isn't definitive. A University of Maryland study released this year said the pesticide is at most a contributing factor. In Europe, neonicotinoids were banned, yet now that decision is under review.
May Berenbaum, an entomologist at the University of Illinois at Urbana-Champaign, said it's very hard to do research on bees, especially honeybees. Most toxicity tests for insects are quite straightforward: You study individual bugs. "They are either twitching or they're not; they're alive or they're dead," she told us.
Honeybees, Berenbaum said, don't lend themselves to simple lab experiments. They exist communally; what happens to them individually isn't of much concern. And they are remarkably sophisticated creatures who commute to work -- flying between hive and field -- using memory, navigation capability and homing behavior. So proving, for example, that a neonicotinoid is poisoning a hive of 50,000 worker bees means, among other things, understanding if the bees "are remembering what they saw this morning or not," Berenbaum said.
The worry about bees is both environmental and economic: if the bees are struggling, we need to understand why.
Most experts don't fear for the existence of the species; instead they say beekeepers are hurt by the high cost of replenishing diminished colonies, and that could have an impact on the quality of American produce. California's almond growers, for example, hire about two-thirds of the country's honeybee colonies from migrant beekeepers each spring to pollinate the fields. If beekeepers are run out of business, we'll see the impact at the supermarket.
There's some buzz about all this in Washington. A White House task force on bee health (who knew?) published a paper this month pushing for a clearer answer to the pesticide question and committing the government to turning more federal land into bee buffets. Those are good goals.
Experts agree that a major issue confronting both honeybees and wild bees is that too much native habitat teeming with delicious plants and flowers gets paved over, mowed under or converted to corn and soybean fields because prices are high. If bees are malnourished, they are more vulnerable to other stresses. Butterflies, another pollinator, face the same food issue.
This is where we can pitch in: Most Chicago-area residents live in proximity to bees, whether wild species or hobbyist honeybees. If you want honey, buy local to support the beekeepers. And for those with access to a yard, stop fussing over it! Let some of your grass grow wild, permit a few dandelions and plant some native bee-friendly species that blossom at different times of year.
The bees will thank you.
