Apis mellifera scutellata
There are many species of honey bees worldwide, but the western honey bee (Apis mellifera) is the most commonly known. Western honey bees (or just honey bees) are a vital part of the US agriculture industry, contributing at least $20 billion in added value to many crops. They provide honey and other hive products, but their most important service is crop pollination. It is estimated that a third of the world’s food supply is dependent on honey bee pollination. Although they have a vital role in agriculture, honey bees are not native to the Americas. Instead, subspecies (races) of western honey bees are native to Europe and Africa. European settlers were first to introduce honey bees into the United States.
There are many races of western honey bee and their use/occurrence varies globally. For example, the most popular race of honey bee worldwide, the Italian honey bee or Apis mellifera ligustica, occurs naturally in Europe. The term ‘African honey bee’ refers to a single race from southern Africa know as Apis mellifera scutellata. The term is misused because there are 10+ races of honey bee in Africa and they are all ‘African’ honey bees. However, for the sake of consistency we will refer to A.m. scutellata as the ‘African’ bee. All races of Apis mellifera can interbreed or hybridize.
In 1956, researchers in Brazil were experimenting with African honey bees in order to improve beekeeping in tropical areas, and the African honey bees were released accidentally. Until then, European races of honey bee were used in the Americas, but their overall production was marginal in the more tropical climates. In contrast, African bees were extremely well suited to the area and began to hybridize with European honey bees. This facilitated their spread at a rate of 200 to 300 miles per year thus earning them the reputation of being the most successful biologically invasive species of all time. It is this hybridization with European honey bees that earned them the name African‘ized’ honey bees. Traditionally, ‘African’ and ‘Africanized’ have been used interchangeably although the former really refers to the pure race and the latter to the hybrid. By 1990, Africanized honey bees had reached the US by entering Texas. As of 2006, they are now established in Texas, California, New Mexico, Arizona, Oklahoma, Louisiana, Arkansas, Alabama, and Florida and their spread continues.
Like other insects, honey bees have three basic body regions: head, thorax, and abdomen. The head has two large compound eyes, three smaller simple eyes, one pair of antennae, and mouth parts. The thorax has two pairs of wings and three pairs of legs. The abdomen is orange-brown with black stripes. Honey bees are commonly confused with bees, wasps or flies that have similar body shape and coloration.
There are three types of individuals within the honey bee’s caste system: worker, queen, and drone. A worker is the smallest individual, about 10-15 mm in length, and is defined as a reproductively underdeveloped female responsible for the tasks of the colony. The queen, typically 18-20 mm in length, is a fully fertile female specialized for producing eggs. The drone, 15-17 mm, is the male bee whose sole purpose is to mate in the air with young queens from other colonies.
Africanized honey bees cannot be distinguished from European honey bees by sight. Laboratory personnel use morphometric analysis to initially identify Africanized honey bees. Morphometry, the measurement of wing venation patterns and the size of various body parts, has been used to differentiate honey bee races since the 1960s. It was first used to differentiate Africanized and European honey bees in South America in 1978 (Francoy et al. 2006). Since that time, an automatic system of digital measurements has been developed to obtain wing measures (Francoy et al. 2006). The latest research has developed a method to accurately distinguish between Africanized and European honey bees using software to calculate angles between the landmarks, cell area, continuous curvature, and arc lengths (11 characters) of the right forewing radial cell in workers (Francoy et al. 2006). The right wings of specimens are placed between microscope slides and photographed with a digital camera attached to a stereomicroscope (Francoy et al. 2006). Using a computer, measurements are made and analyzed using specific software and classification is made accordingly. A more rigorous identification is achieved by genetic analysis. You should immediately contact your local cooperative extension agent if you suspect Africanized honey bees. A sample of 50 to 60 honey bees is needed for identification.
To the casual bystander, the primary identifying characteristic for Africanized bees is their enhanced defensive behavior compared to that of European bees. Selection pressures induced by man are, in part, responsible for this heightened defensiveness. ‘Beekeeping’ (man-managed honey bee colonies) is more common in Europe where the native honey bees have been bred for gentleness and ease of management. In contrast, ‘honey hunting’ (near-complete destruction of hive to harvest contents) was more common in Africa resulting in a bee that is more defensive.
Africanized honey bees swarm and abscond in greater frequencies than their European counterparts. Swarming, bee reproduction on the colony level, occurs when a single colony splits into two colonies. The old queen leaves the original nest with about 60% of the population and they establish a new nest elsewhere. The parent colony subsequently requeens itself. European colonies commonly swarm 1-3 times per year. African colonies may swarm greater than 10 times per year. African swarms tend to be smaller than European ones and the swarming bees are docile in both races. African bees have a tendency to abscond (completely abandon the nest) during times of dearth or of frequent disturbance. At this time the entire colony moves to another location.
Undergoing complete metamorphosis, honey bees progress through four developmental stages: egg, larva, pupa, and adult. The queen lays her eggs in wax cells built by workers. Fertilized eggs result in females, either workers or queens. If fed a diet rich in royal jelly, the larva will develop into a queen. When feeding on a diet low in royal jelly, the larvae mature into workers. Unfertilized eggs result in drones. Developmental time varies by caste member. For European honey bees, the number of days until an adult emerges for workers, queens, and drones are 21, 16, and 24, respectively. The same for African honey bees is 19-20, 14, and 24 respectively.
In general many flowering plants are hosts to honey bees, although some are more attractive than others. Africanized honey bees are not selective in where they will nest and have been found in a variety of locations. They will occupy a much smaller space than European honey bees and have been found in water meter boxes, cement blocks, old tires, house eaves, and almost any abandoned structure. The nesting habits of Africanized bees increases encounters with humans. Removal of honey bee colonies from an area opens the area to potential colonization by Africans when they move into an area.
Africanized honey bees have caused problems to humans due to their selection of nesting sites and defensive behavior. Children and elders are at the highest risk due to their inability to escape an attack. Africanized honey bees are also agitated by power equipment, such as tractors or lawnmowers. There are precautions that can be taken if Africanized honey bees are an area. The Florida Department of Agriculture, Division of Plant Industry offers advice on how to avoid or prepare for an attack.
- Remain alert for bees, be aware of surroundings
- Walk away and stay away if you see a swarm or nest.
- Teach children to use caution and respect all bees and other insects.
- Obtain bee sting kits.
- If a nest is found, contact your local county agent for assistance in having it removed. (a local pest control operator to remove it).
If an attack occurs:
- If attacked, run away in a straight line. Running through tall grass or small trees will help to disrupt your image from the bees and can help one avoid stings until cover can be found. DO NOT STAND AND SWAT AT BEES. Remember, they are defending their nest and you need to get away from that nest as fast as possible.
- Cover your face and eyes by pulling your shirt over your head.
- Get into a car or house
- DO NOT jump into water. The bees will wait for you at the surface.
- If stung, remove stinger quickly by scraping it out
- If breathing is affected, immediately see a doctor.
- If in the woods or camping or fishing/hunting carry a can of DEET and spray it on the attacking bees to help break up the attack.
The Florida Department of Agriculture, Division of Plant Industry offers several steps that can be followed to create a safe environment.
- Eliminate possible nesting sites by removing any unnecessary “junk” from the area.
- Check walls and eaves of structures regularly
- Close off wall, chimney, electrical and plumbing-related gaps that are more than 1/8” large with a small-mesh hardware cloth (8-mesh or higher) or caulking
If a nest is found, immediately contact your local cooperative extension service or the state Department of Agriculture for a list of beekeepers or pest control operators for advice or assistance.
- Find your state’s cooperative extension service http://www.csrees.usda.gov/qlinks/partners/state_partners.html
- Find your state department of agriculture contact: http://nationalplantboard.org/member/index.html
- Francoy, T. M., Prado, P. R. R., Goncalves, L. S., Costa, L. F., DeJong, D. 2006. Morphometric differences in a single wing cell can discriminate Apis mellifera racial types. Apidologie 37: 91-97.
- Caron, D. M. 2001. Africanized Honey Bees in the Americas. The A. I. Root Co., Medina, Ohio.
- Graham, J. M., ed. 1992. The Hive and the Honey Bee. Dadant & Sons, Hamilton, Illinois.
- Winston, M. L. 1987. The Biology of the Honey Bee. Harvard University Press, Cambridge, Massachusetts.
- Florida Department of Agriculture & Consumer Services, Division of Plant Industry. African Honey Bee.
- Honey Bee Research and Information at the University of California, Riverside
- USDA-ARS Carl Hayden Bee Research Center. Africanized honey bees.
- USDA National Invasive Species Information Center. Africanized honey bees.
- Global Invasive Species Database. Apis mellifera scutellata.