http://www.ars.usda.gov/research/publications/publications.htm? SEQ_NO_115=155925 <<We examined nest usurpation (colony takeover) by African honey bee swarms over a two-year period in an apiary that contained 76 European colonies maintained in Tucson, AZ. We observed a mean annual usurpation rate of 21%, with highest usurpation rates occurring from October- December.>> -- Visit www.honeybeeworld.com/bee-l for rules, FAQ and other info ---