So-called killer bees have reportedly arrived in Tucson, Ariz., early this year, with a shortage of food on the desert causing colonies to move about.
The Africanized bees have been forming new colonies around the city since at least February, while that activity doesn't usually begin until the middle or end of March, the Arizona Daily Star reported Thursday.
Scientists believe the ongoing drought over the southwester United States has reduced the amount of food available for existing urban colonies or in the desert where many of the bees normally live.
"The bees are kind of confused," said Justin Schmidt, a research biologist and Africanized bee expert, told the newspaper. "Normally, in January and early March, there will be lots of flowers from early rains in the desert -- mesquite, mustard and mistletoe -- that provide good food for them.
"This year we haven't had any of that. You walk around in the desert and there are no flowers. The bees are kind of starving," he added.
Copyright 2006 by United Press International
Explore further: Rosetta comet-landing is Science's 2014 breakthrough