Heat troubling for bees

The record-breaking triple-digit temperatures are not only wreaking havoc on humans, but on honey bees.

On days when temperatures exceed 100 degrees, bees collect more water to cool the hive to protect the brood (immature bees) and ward against a meltdown, said University of California, Davis, bee specialist Susan Cobey.

She said bees reduce their flight activity for nectar and pollen, but collect more water. They spread droplets of water and then fan their wings to ventilate and cool the hive.

"When the heat is really intense, the worker bees rev up the fanning and water circulation," said Cobey, a bee breeder and geneticist at the Harry H. Laidlaw Honey Bee Research Facility, part of the UC Davis Department of Entomology.

Beekeepers know to locate their hives in shade and near ample water, such as a drippy faucet.

"Beekeepers will often crack a hive to provide more air flow and if the bees don't like it, they'll plug it (the hole) with propolis (plant resins collected by bees that serve as a cement or bee glue)," Cobey said.

UC Davis entomologist Lynn Kimsey said that honey bees must keep the temperature inside the hive around 92 to 94 degrees.

"That's a real problem when the temperature outside reaches 100 or 105 or more," Kimsey said.

"You'll see honey bees collecting water everywhere, from around leaky faucets, and in puddles, bird baths, fish ponds and swimming pools -- anywhere there's water," Kimsey said.

Worker bees do all the work to maintain the hive. In addition to gathering nectar, pollen, propolis and water, they serve as air conditioners, architects, construction workers, nurses, dancers, guards and undertakers. However, bees don't work in foul weather: rain, heavy fog, or in a wind of more than 15 miles per hour, and they don't like the heat.

Contributions to UC Davis Honey Bee Research Facility can be made online by accessing the Department of Entomology Web site at
http://entomology.ucdavis.edu/home.cfm.

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