LOST HILLS, Calif. — Almond trees are exploding with pink and white blossoms across the vast Central Valley, marking the start of the growing season for California's most valuable farm export.
Toiling among the blooms are the migrant workers that will make or break this year's crop: honeybees.
The insects carry the pollen and genetic material needed to turn flowers into nuts as they flit from tree to tree. It's a natural process that no machine can replicate. But it can't be left to chance. Bees are too integral to the fortunes of California's nearly $3-billion-a-year almond industry.
So each year beginning in early February, hundreds of beekeepers from around the country converge on California's almond farms with their hives in tow. Lasting about four weeks, it's the largest such pollination effort on Earth: 1.6 million hives buzzing with 48 billion bees across a cultivation area about the size of Rhode Island.
"Without the honeybees … the (almond) industry doesn't exist," said Neal Williams, an entomologist and pollination ecologist at the University of California-Davis. "We need those bees. We need them to be reliable, and we need them at the right time."
But a mysterious malady known as colony collapse disorder has wreaked havoc on the U.S. bee population in recent years, stoking fears among almond producers and other farmers that depend on the insects for their livelihoods.
Between 2003 and 2009, the number of bee colonies in California plunged 26 percent to 355,000, according to the U.S. Department of Agriculture. Eric Mussen, another UC-Davis bee expert, said no agency has a precise count; he believes those federal hive statistics to be too low. Still, he too estimates that the state lost about a quarter of its hives over that time period.
Although California bee populations have recovered a bit, almond farmers are still feeling the sting. Prices to rent bees have tripled since 2003-2004 to as much as $160 a hive because of tight supplies and rising expenses for beekeepers to keep their colonies healthy. Collectively, California growers will spend about $250 million on bees this year.
Scientists believe that colony collapse disorder is a combination of ailments that includes mites, malnutrition, stress and fungi.
Even in relatively normal years, those factors can claim a third of a hive's population, said beekeeper Bryan Ashurst.
A fifth-generation California beekeeper with 12,000 hives filled with about 360 million insects, Ashurst said the creatures are surprisingly delicate.
"It takes time to build a hive," Ashurst said. "But it can collapse really quickly."
After hitting a low in 2007 of about 340,000 hives, according to the USDA, the number of managed bee colonies in California is rising. Other industry experts put the colonies at about 500,000, up from a low of around 400,000.