Hive talkin': The heat's not so sweet for the bees

Issue Date: August 16, 2006

By Ching Lee
Assistant Editor

 

When flowers are in bloom, bees keep themselves busy gathering pollen to make honey. But during last month's extreme hot weather, the little critters were too busy trying to stay cool.

Unlike many livestock owners who suffered severe losses during the heat wave, California beekeepers say the honey makers mostly made out OK.

That's good news for California almond growers, who will need the busy bees to pollinate their orchards in the spring.

Bees know how to survive pretty well in the heat, said Eric Mussen, apiculturist for the University of California Cooperative Extension.

"Bees can make it at 120 degrees day after day after day," he said. "We know that because they can make it in the Imperial Valley, and that's the way it is in the summer."

The bees keep cool by collecting water and placing droplets inside the hive. By flapping their wings, they create a breeze that acts as a natural air conditioning system.

"Basically the colonies are cooled by evaporation, just like a swamp cooler," said Gene Brandi, a beekeeper in Merced County. "That works very well, but when it gets as hot as it did last month, it's really too hot for the bees to be out working flowers, so about the only bees that are flying are the ones collecting water."

Honey producers will likely see a shorter honey crop this year, but it would be hard to quantify at this time, Mussen said. The bees still venture out for pollen, but they limit their time to early mornings or late in the day when temperatures are milder.

Smaller and weaker colonies, such as those used to raise queens, are most vulnerable during extreme weather because there are not enough worker bees to cool the hives and provide food for the queen and brood nest.

Shannon Wooten, a bee breeder in Shasta County, said the prolonged cool spring delayed his production of queens this year, and the sudden heat spell further foiled his chances of raising enough queens to satisfy customer demands, resulting in his losing $300,000 worth of business.

Due to the high price of pollination, many beekeepers are trying to increase their hives to meet the growing demand for bees for almond pollination. Nevada County beekeeper Gary McClaughry said his new hives survived the heat but the small colonies were not able to keep the brood nests cool enough, so he lost a generation of younger bees.

"In the new hives that I started, it definitely set them back," he said. "The bottom line is it's going to mean more work and more expense on our part, but I don't think there's going to be any harm for the upcoming pollination season."

Another concern beekeepers have is that the scorching temperatures in July dried up much of the food source that bees forage as they prepare for the fall and winter seasons, said Mussen. There are supplements to help, but they are not as good as the natural pollen source.

The challenge is finding areas to take the hives where plants are still in bloom. Many beekeepers scout the foothills and mountain regions, where the star thistle are usually plentiful. The prickly summer-blooming plant is an annoying weed for farmers and ranchers but "a savior plant for bees," Mussen said.

"The problem with this year was, the grasshoppers took most of the star thistle," he said. "So all of a sudden, you don't have that nectar and pollen source that you normally have in the summer."

But bees find other sources--such as in melons, squash, cucumbers, sunflowers and safflowers. Cotton, which blooms through September, provides one of the biggest honey crops in California, Mussen said. Native plants such as blue curl and tarweed are traditionally great pollen sources in the fall, but this year they are harder to find because the heat cooked many of them dry, Brandi said.

Supplying bees with a good food source is critical this time of year when the bees are trying to multiply and store enough honey to make it through the winter.

"Now we're trying to produce some of these winter bees that we hope are going to have up to a six-month life expectancy," said Mussen. "The bees that are coming now are the ones we hope will make it through the winter and still be around at almond time."

One problem that beekeepers are still trying to keep at bay is the varroa mite, a bloodsucking parasite of honeybees that can devastate colonies if left uncontrolled.

"People are trying to stay ahead of it, but I think it's still a huge problem for beekeepers," said Valeri Severson, a beekeeper in Sutter County. "We've already had a couple of products that have become ineffective, and it's always difficult to get new products on the market and get them registered in California."

Although the bee supply has traditionally been short during almond pollination, Severson said the beekeeping industry has a good network to help meet the demand. She noted that there was actually a surplus of bees this year.

"This past spring there were some beekeepers from out of state that came in thinking that almond farmers were there with their checkbooks," she said.

But many almond growers now have contracts to ensure that they get their bees at a reasonable price, she said.

(Ching Lee is a reporter for Ag Alert. She may be contacted at clee@cfbf.com.)

Permission for use is granted, however, credit must be made to the California Farm Bureau Federation when reprinting this item. Top