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Taxonomic name: Apis mellifera scutellata (Lepeletier) Synonyms: Common names: Africanized honeybee (English), Brazilian bees (English), killer bee (English) Organism type: insect Warwick Kerr brought Apis mellifera scutellata from Africa to South America in 1957 to help revive the failing Brazilian bee-keeping industry. He was using various European subspecies of Apis mellifera L., unsuitable for the South American environment. The queens and workers of several colonies were accidentally released and these aggressive bees hybridised with local colonies. A. m. scutellata has gradually spread ever since, causing economic, social, and ecological problems. Description Apis mellifera scutellata is 3/4 inch long, covered in fuzz, and brownish with black stripes that are not as distinct as those on hornets. It has 4 clear wings and 6 legs. Please see PaDIL (Pests and Diseases Image Library) Species Content Page Bees: Africanized honeybee for high quality diagnostic and overview images. Similar Species Apis mellifera More Occurs in: agricultural areas, natural forests, planted forests, ruderal/disturbed, urban areas Habitat description Apis mellifera scutellata is less selective in its habitat preferences than A. mellifera . A. m. scutellata can be found in tree hollows, rotted logs, and in many manmade structures, such as wood and rock piles. They are limited to tropical and subtropical habitats because they are accustomed to a wet and a dry season, as opposed to the hot and cold seasons associated with temperate regions. General impacts Apis mellifera scutellata are aggressive bees that defend their nest from intruders up to 50 feet away by stinging in the hundreds and chasing intruders up to a mile. They have caused deaths of pets, livestock, and even people, giving them their "killer bee" nickname. People and other animals are usually killed only if they are unable to get away. A. m. scutellata 's largest impacts are economic and ecological. They affect the beekeeping industry by competing with A. mellifera, causing them to produce less honey and taking over the A. mellifera nest by killing its queen and replacing it with their own.It should be stressed here that their main impact is not by taking over colonies through killing queens, but rather through mating. Beekeepers' business is threatened by the high labor costs of workers willing to harvest A. m. scutellata honey and frequently re-queen nests. It is also a concern that some ecosystems could be at risk because A. m. scutellata outcompetes native pollinators when they invade their territory. Uses Apis mellifera scutellata provides pollination services in the tropics. Some farmers believe they are beneficial to their crops because they provide superior pollination to A. mellifera . Notes Unlike Apis mellifera , Apis mellifera scutellata does not hoard honey over the winter. Instead they depend on colony mobility (absconding and swarming) to find new sources of food, water, or space if one or all run out. Geographical range Native range: Apis mellifera scutellata is native to eastern and southern Africa. Known introduced range: They were introduced to Brazil and spread throughout South America, Central America, and into Arizona, California, New Mexico, Nevada, and Texas. Introduction pathways to new locations Agriculture: Introduced to help the honey industry in Brazil as they were better adapted to South America. Natural dispersal: Management information Preventative measures: To prevent Apis mellifera scutellata from interbreeding with commercially reared A. mellifera, the area is flooded with A. mellifera drones, limiting the possibility of mating with A. m. scutellata . Frequent re-queening is also done to ensure A. mellifera queens are maintained. Another strategy is to inject A. mellifera sperm into an A. m. scutellata queen, which produces less aggressive bees. Integrated management: Many countries try to destroy the bees with chemicals and traps, however, this strategy however is not very effective. Nutrition Bees feed on nectar and pollen. The nectar is converted into honey and is the bee's principle source of carbohydrates, while pollen is the source of protein. Africanised bees often depend on their increased rate of colony mobility (swarming) as a response to seasonal fluctuations in food supply. European honeybees are better at hoarding vast amounts of honey and surviving long, cold winters (Kurzmann, undated). Reproduction The queen mates with a drone to create a fertilised egg, which becomes a female worker bee. The queen also produces unfertilised eggs, which become male drones. Eggs become queens if they are fed (when they are larvae) large quantities of an extremely nutritious creamy white liquid -royal jelly, a mix of hypopharyngeal and mandibular gland secretions. One queen can produce 1500 eggs a day. Swarming is more important than queen egg laying. Colonies reproduce by frequent swarming, and one colony can result in 17 colonies after a year when both reproduction and mortality are taken into account. Lifecycle stages Apis mellifera scutellata eggs become larvae, metamorphosise into pupae, and then grow into adults. This cycle takes about 18.5 days for worker bees and about 16 days for queens. Worker bees have a lifespan of about 30 days, drones around 5 to 10 weeks, and queens live from 1 to 3 years. Reviewed by: Mark L. Winston, Professor and Fellow, Morris J. Wosk Centre for Dialogue, Canada. Compiled by: National Biological Information Infrastructure (NBII) & IUCN/SSC Invasive Species Specialist Group (ISSG) To contribute information, please contact Shyama Pagad. Last Modified: Tuesday, 25 October 2005