Bad news for apiphobes: “Killer” bees are on the move in the United States. Scientists from the University of California, San Diego recently collected hundreds of bees around the Golden State to determine how far north hybrid honeybees, or Africanized bees, have spread since they first arrived in the state in 1994. They found that Africanized bees — which possess genes from both European and African honeybees — now live as far north as California’s delta region (about 25 miles, or 40 kilometers, south of Sacramento).

And in the southern part of the state, so-called “killer” bees run the show. About 65 percent of the honey bees that buzz around San Diego County have a mix of European and African genes, the researchers found. “The pattern of Africanization we documented in San Diego County and elsewhere in California appears consistent with patterns previously documented in Texas, where Africanized honey bees first appeared in the United States,” Joshua Kohn, a professor of biology at UC San Diego and co-author of the new study, said in a statement. FULL REPORT