In 2007, the world was introduced to a plague so disturbingit seemed almost biblical. out of the blue, honey bees were dropping dead orworse, vanishing into the air by the millions. in the four years since, colony collapse disorder (CCD) hasbeen a regular resident on newspaper front pages as scientists desperately tryto puzzle out what’s wrong.
Certainly the stakes are high, considering that 35 percentof the world’s crops — amounting to $216 billion per year — depend on various creatures toferry pollen from one flower to another. And certainly, if scientists cannothelp honey bees recover, it could dramatically affect the price of food.
What is not so certain is whether the familiar honey bee isreally the only game in town.
“the alfalfa leafcutting bee has been in commercial use sincethe late ’50s, early ’60s,” says UC Davis professor emeritus Robbin Thorp. “Sincethe early ’90s, bumble bees have been commercially produced for tomatogreenhouse production and in a number of outdoor crops where honey bees are notthe most effective pollinator. Like blueberries and cranberries.”
Thorp is the patriarch of a rag-tag group of scientists whohave pioneered research on non-honeybees that just may hold a solution to the world’s pollination problems. Forthose who don’t own boxes of pinned and labeled bugs, it may come as a surprisethat most of the world’s bees don’t live in hives or make honey. in fact, Californiaalone has some 1,600 species of native bees, with names like the blue orchardbee, the squash bee and the teddy bear bee (this is not counting wasps andyellow jackets, which many bee researchers sarcastically call “ants withwings”).
They may be green or brown, shiny as a chrome fender orfurry as an ape, big as a bumble bee or barely visible to the human eye. Butalmost all of them can pollinate flowers — some of them quite well. this wasthe conclusion of a seminal 2002 paper by three UC scientists, including Thorp,in “the Proceedings of the National Academy of Sciences.”
Messy but effective
In some cases, native bees — which often don’t have tidypollen pouches on their legs — are messier than honey bees, and thus better atspreading pollen around. in other cases, natives just shake more loose. Infact, tomato farmers may see 50 percent more tomatoes that are twice as big ifthey get regular bumble bee visits.
“We’ve known for a long time that native bees can beeffective pollinators. the problem in my mind is: can we take that informationand implement it?” says Gordon Frankie, who hasstudied native bees at UC Berkeley for several decades.
So why the global obsession with the one species that makeshoney? for one, honey bees have hives, which makes them easy to keep andtransfer en masse. for another, some native bees are picky about which flowers they preferand where they live. as a result, commercial pollination is almost whollydependant on honey bees.
“we are very much reliant on honey bees, for almonds forexample. they require a huge number of pollinators,” says Claire Kremen, UCBerkeley conservation biologist and lead author of the 2002 PNAS paper.
Almonds may be the most bee-dependent crop in America.Without pollinators, the trees simply cannot create fruit. Every February,almond farmers pay $300 per acre for beekeepers to pollinate their land — aprice that has tripled since the 1990s.
So in 2003 Kremen teamed up with the Xerxes Society, anon-profit group that many call “Audubon for invertebrates.” together, Xerxes and UC scientists have been making the caseacross the country that while native bees can never replace honey bees, theymay provide a crucial insurance policy.
To employ native bees, farmers must lure the insects ontoa farm field with hedgerows of specific flowers they know the bees like. It’s asimilar strategy to the one employed by organic farmers who invitepredatory insects like ladybugs to rid their crops of pests.
“We’re all worried about colony collapse disorder,” says“Farmer Al” Courchesne of Frog Hollow Farms. “if nativebees could step up and provide a service to ameliorate that difficulty, thatwould be a very big deal.”
Frog Hollow, a small organic farm inBrentwood, Calif., is partnering with Frankie in a 10-year experimentto attract native bees. meanwhile, Kremen and Neal Williams at UC Davis areworking with 30 farms ranging in size from 2 to 80 acres. the goal of all this work isnot to replace honey bees, but to pinpoint which native bees are effective,what they can offer and how to lure them into visiting and pollinating.
“Putting hedgerows around avery large 300-acre monoculture is like putting a Band-aid on awound that needs a tourniquet,” Kremen says. “but it doesn’t have to be aneither/or kind of thing.”
Creating buffet forbees
Scientists are realizing that a combination of pesticides, pathogens andpoor nutrition probably are the major causes of CCD. Prominent theories suggestthe stress of moving from one pesticide-rich monoculture to another makesfarmed bees vulnerable to sudden virus outbreaks. on the other hand, a diversefarm sprinkled with various crops and flowers gives all bees — native andhoney-making alike — a healthy diet.
Of course, this kind of bee buffet works better on organicfarms than massive industrial operations. nevertheless, the idea to use nativepollinators has spread over the last few years from California to farms acrossthe country, all the way to Washington, D.C. Nationwide 60,000 acres ofpollinator-specific habitat will be put aside over the next year or two. In2009, the U.S. Department of Agriculture’s Natural Resources ConservationService set aside $330,000 from the farm bill for pollinationprojects in California as well as some of the largest blueberry and cherry operations in Florida,New Hampshire and Oregon.
“Farmers really are stewards of the land. they believe intrying to do things the right way,” says Jessa Guisse, who works with Xerxes toeducate and partner with California farmers. She relies heavily on sciencecoming out of UC Davis and Berkeley to help inform farmers.
“the work out at the UC is some of the best work in thecountry right now,” says Mace Vaughan, who oversees national pollinator work for Xerxes. “they areactually demonstrating the benefits.”
But coming up with specific bee instructions for farmers ishardly straightforward. Differing bee tastes are just the start; they also needsomeplace to live. Most native bees nest in the ground, while others occupytubular tunnels, and a few even drill holes in wood. plus, they may not emerge to start pollinating at the same time of year as honey bees. Farmers wanting to attract native bees have to be careful about plowing their fields and knowing when native bees are likely to become active.
UC Davis’ Williams is working on a way to perhaps pinpointbee hotspots throughout the state to concentrate efforts. even so, it may be decades before scientistshave a clear understanding of how the diverse tapestry of native bees affects afarm field.
It may be worth it, though. Kremen is still determining thedollar value of native bees, but she says even with minimal effort, farmers may already be getting 25 to 30 percent of their pollination for free from beesthey have never heard of. That likely translates to billions of dollars evenbefore the first honey bee touches down. And increasingly farmers are starting tosee a potential savior in their own back yard.
“nothing beats taking a farmer out to squeeze squash flowers(in their fields) and finding squash bees,” says Vaughan, who often leads farm bug-findingtours. “And the farmer suddenly says, ‘I get it.’”
See sidebar: Wild bee research at UC Natural Reserve System