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Communication and Recruitment to Food Sources by Apis mellifera

The ability of honey bees to share information about floral patch feeding sites breatly helps their colonies achieve efficiency in foraging. Whenever a scout bee discovers a new rich food source, she recruits nestmates to it and thus helps ensure that her colony's forager force stays focused on the richest available patches. The majority of this recruitment is by the waggle dance, a unique form of animal behavior in Apis, in which the returning forager seems to perform a miniaturized "reenactment" of her recent journey. Other bees attending these dances somehow (just how they do is not known) learn the distance, direction, and odor of the flower patch and can translate this information into a flight to the original flowers. The waggle dance has been acclaimed as a truly symbolic message, one which is seperated in space and time from both the actions on which it is based, and the behaviors it will guide. Our understanding of this system is due mostly to the pioneering work of the late Karl von Frisch (shared a Nobel Prize for these studies) and his students and colleagues, research which now spans 70 years.

The round dance is performed for food sources close to the colony (less than 50-80 m) and the waggle dance used for distant floral sites. Round dances elicit flight and searching (by olfactory and visual cues) behavior for flowers close to the hive but without respect to any specified direction.

WAGGLE "DANCE"

Scout bee or recruit locates a rich flower patch, imbibes some nectar and flies home.

She crawls onto the vertical combs near the nest entrance and dances for up to several minutes.

The dance amidst closely packed adjacent bees consists of running through a small figure eight pattern repeatedly.

Here a straight run followed by a turn to the right to circle back to the starting point, another straight run, followed by a turn and circle to the left, and so on in a regular alternation between right and left turns after straight runs constitutes the dance.

The informative portion of the dance is the straight run where the dancer vigorously vibrates (waggles) her abdomen back and forth laterally and emits strong substrate and airborne vibrations in addition to audible (to humans) buzzes.

This buzzing is produced by the flight muscles and has a frequency range between 200 - 300 cycles per second.

Several dances may be attended by a new recruit before she leaves the colony to locate the food.

The direction and duration of straight runs are closely correlated with the direction and distance of the flower patch advertised by the dancing bee.

Flowers located directly in line with the sun are represented by waggle straight runs in an upward direction on the vertical combs, and any angle to the right or left of the sun's position is coded by a corresponding angle to the right or left of vertical (see attached figure). The angle between vertical and the straight waggling run of the dance is equal to the angle between the sun (its azimuth not its elev. above horizon) and the flight direction from hive to the food source.

The distance between nest and target appears to be encoded in the duration of the straight runs, since this is the feature of the dance which exhibits the highest correlation with distance to the goal. The farther away the target, the longer the straight runs, with a rate of increase of about 75 milliseconds per 100 meters.

Dancing bees also communicate floral odors which cling to their setae and waxy cuticle.

Bees will forager several km from the nest (usually 1-5) up to a maximum of about 12-14 km, and can recruit nestmates this far from the colony.

The details of the dances' precision and accuracy are not entirely known since in most cases bees rarely forager closer than 500 m from their nest, while bee researchers have traditionally not worked with feeding stations greater than 300 m away. For targets 60-400 m away, the average recruiting accuracy is + 11% (about 25 m). Many bees which attend dances never arrive at food sources, or take much too long to arrive than if they simply flew nonstop in the proverbial "beeline". Waggles about 13-15/second. Dance tempo slows down with increasing distance to the food source.

Decision-making by colonies

The Information-Center Strategy of Honey Bee Foraging (Dr. Tom Seeley)

Forage patch selection by honey bee colonies is an automatic outcome of the simultaneous operation of the following three basic processes:

  1. Workers abandon floral patches of relatively low profitability,
  2. Workers usually locate new patches by following recruitment dances, not scouting on their own,
  3. Workers recruiting only to patches of relatively high profitability.
The net effect of these behavior patterns working in concert is a steady, gradual migration of a colony's foragers off poor and onto rich food sources.

Bees will also dance to indicate location of water, propolis and cavities for new nest sites. Other dances; jostling run, spasmodic dance, buzzing run, shaking dance, trembling dance. DVAV = vibration dance, can be very common. Worker vibrates its body dorsoventrally while grasping another worker or the queen. Used somehow to regulate foraging and swarming (queen emergence), regulate daily and seasonal foraging patterns.

PLEASE NOTE:



Not all bee scientists, or biologists, believe in every aspect of the "dance language" as formulated by Karl von Frisch and modern proponents. For example, we know almost nothing about which combination of biophysical signals (vibrations, odors, vision) are transmitted from dancer to "attendant" bees and how they use this information once they leave the hive. We do know that bees often follow many dances and that their recruitment is not a landmark of precision. Many bees simply fail to find the food source or may stumble upon it by following floral aromas or even other bees in flight to and from a rich floral patch. This area of research has become highly dogmatic and anyone who doubts or publicly questions even the smallest details of the dance language hypothesis may be subject to ridicule and personal attacks. Please keep an open mind and read all that you can about this fascinating bit of animal behavior and insect communication. Please remember, however, that honey bees are afterall just insects with very small brains. They have no mysterious abilities that other social bees, or other insects do not posess.

Further Reading

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