Solitary Bees

Most bees are solitary or, at most, communal or semiso-cial. Some species of the family Halictidae, which include the sweat bees, are in fact true social bees. A few of the solitary communal and social species form dense nesting aggregations, usually in soil, where they excavate cells in which to rear their larvae. Larvae of all bee species feed on pollen and nectar provisioned in these cells. Nesting activity is quite variable, ranging from a single nest to

FIGURE 19.27 Head of German shepherd dog in fatal case of attack by Africanized honey bees (Apis mellifera). Note the concentration of bee stings about the eye. (Photo by J. Schmidt.)

FIGURE 19.26 Honey bees (Apis mellifera) on surface of comb in hive. European honey bee (center), surrounded by Africanized honey bee workers. (Courtesy of Entomological Society of America.)

dampened the defensive tendencies of many races, honey bee colonies can still attack and sting intruders in large numbers.

The perennial colonies of honey bees usually survive the winter, and in late spring through early summer they reproduce by swarming. Swarms often are seen resting in exposed sites such as trees, shrubs, and under eaves of buildings while they are seeking a suitable cavity in which to establish a new hive. Although these swarms are less defensive than an established colony because they lack brood, stored pollen, and honey, it is best not to approach or disturb them.

Of particular concern in the United States is the northward movement of the Africanized honey bee (A. mellifera scutellata), an aggressive subspecies of the common honey bee that has spread in recent years through tropical regions of South and Central America. It is most abundant in tropical, humid areas of Africa but extends into arid regions of South Africa. This honey bee was introduced into Brazil in 1956 in an effort to improve the beekeeping industry in Latin America. Captive bees escaped in 1957 when queen excluders were removed from some of the hives. They spread south to Argentina and north through South America, reaching Panama in 1982. The first Africanized honey bee colony trapped in the United States was in 1990 in Texas. As of 1996, colonies have been discovered in south Texas, New Mexico, Arizona, California, and Puerto Rico.

This bee quickly establishes itself in new areas. When foraging or nesting conditions become restrictive, the bees leave their hives in a process called absconding and relocate to new nesting sites. Other subspecies of the common honey bee become established more slowly

FIGURE 19.27 Head of German shepherd dog in fatal case of attack by Africanized honey bees (Apis mellifera). Note the concentration of bee stings about the eye. (Photo by J. Schmidt.)

in new areas and are less likely to abscond when conditions change.

The Africanized honey bee has a propensity for mass-stinging attacks of both people and animals (Fig. 19.27). Detailed, quantitative studies have shown that these bees are much more alert than other subspecies to movement, vibration, and their own pheromones that mediate alarm and attack responses. The alarm compounds are not released in greater quantity by Africanized bees, but rather the threshold of response of the bees to a perceived threat is much lower. Nor is their venom any more potent than that of other A. mellifera subspecies; in fact, the composition is nearly identical.

Aside from their behavorial differences, individual Africanized honey bee workers are indistinguishable from workers of the European subspecies of A. mellifera. It requires a specialist to examine and measure specific morphological (e.g., wings) and biochemical features of several bees to determine their identity. While the Africanized honey bee stings much more readily than the European honey bee, so far deaths of animals and humans due to A. mellifera scutellata are not common. About 350 human deaths in Venezuela between 1975 and 1988 were attributed to Africanized honey bees (Winston, 1992). Since they reached Mexico in 1986, the bees have reportedly killed several dozen people. Annual fatalities due to bee stings in Texas have not increased since this bee arrived there in 1990.

Stinging problems due to the Africanized honey bee are actually less of a concern than the potential disruption to beekeeping and agriculture. The bees are more difficult to manage and store less honey than their

European counterparts. These traits, coupled with their extremely aggressive nature, have raised great concern for beekeeping in North America, which relies upon organized transport of many managed hives for pollination services. Also, the impact on tourism and recreation in Africanized honey bee areas could be considerable.

The future status and distribution of the Africanized honey bees in North America is controversial. Winston (1992) presented several predictions on the northernmost limit of the spread of this bee and stated that the most likely distribution is an Africanized zone extending through the southern one-third of the United States. The U.S. Department of Agriculture in 1984 predicted that the impact on beekeeping and agriculture in the United States will be U.S. $26-58 million in annual losses to beekeepers and an additional $93 million in annual losses due to diminished pollination of crops. The impact may be lessened by modifying hive management practices (e.g., requeening with docile European queens), thereby altering their genetic makeup by interbreeding with European strains. As the bee dispersed throughout tropical and subtropical areas of South and Central America, there were relatively few beekeepers in the areas traversed. However, now that the bees are in the United States, the management practices of thousands of beekeepers are expected to modify the behavior of the bees by interbreeding these bees with the more docile commercial colonies.

Bee Keeping

Bee Keeping

Make money with honey How to be a Beekeeper. Beekeeping can be a fascinating hobby or you can turn it into a lucrative business. The choice is yours. You need to know some basics to help you get started. The equipment needed to be a beekeeper. Where can you find the equipment you need? The best location for the hives. You can't just put bees in any spot. What needs to be considered when picking the location for your bees?

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