Comparative Foraging Behavior of Six Stingless Bee Species Exploiting a Standardized Resource

Abstract

We report on differences in foraging and recruitment patterns among 6 stingless bee species simultaneously exploiting a large grid of baits in a tract of tropical dry forest in Costa Rica. Comparative data for the species were obtained on the following parameters of foraging: time to initial bait discovery, rate of discovery of additional baits, rate of worker recruitment, time till attainment of approximate steady—state number of workers and visited baits, frequency of number of workers per bait, degree of site constancy of foraging within and between days, and responses to presence of intraspecific and interspecific rivals at baits. All species had unique aspects to their foraging, which reflected whether the species mark food sources and lay trails with pheromones, the degree to which workers forage solitarily, and their use of aggression. The behavior of Trigona fuscipennis, the pheromone—using group forager, was particularly distinctive. It found baits the most slowly, was the most site constant, and excluded all other bees from its baits. We hypothesize that in group foragers, extreme localization of workers and resultant slowness of discovery of new food sources represent a trade—off for the advantages of group defense of good sources. Other responses to rival bees included bullying tactics by lone, marauding workers of the large, facultative recruiter, Trigona silverstriana, and persistent, opportunistic insinuation by small, solitary foraging species. Spatial segregation of foraging location between the species increased over time on each day of the experiment, especially among interspecifically aggressive species. The observed diversity of tempo and mode of foraging reinforces the hypothesis that coexistence among these apparently food—limited social bees does not result from the simple partitioning of food resources by size or taxon, but from rather subtle partitioning based upon diversity in the timing, persistence, renewal rate, and spatial dispersion of their limited food resourves.

A stingless bee marks the feeding site in addition to the scent path (Scaptotrigona aff. depilis)

“…The remarkably precise localization of a food source in scent path laying stingless bees, as shown by several authors (Lindauer andKerr, 1958, 1960;Kerr et al, 1963;Hubbel and Johnson, 1978) and confirmed by our present work, seems to contrast with less precise localization of food sources in non-scent path laying bees of the genus Melipona (Lindauer andKerr, 1958, 1960;Kerr et al, 1963;Nieh and Roubik, 1995;Nieh and Roubik, 1998;Jarau et al, 2000). In Melipona sp.…”

“…In the latter case the precision of the recruitment system is highly important for the colony's food acquisition (Visscher and Seeley, 1982;Seeley and Visscher, 1988;Seeley et al 1991, Waddington et al, 1994. Scent trail laying stingless bees, on the other hand, seem to be particularly good at the exact localization of a food source and its exploitation until it is depleted (Hubbel and Johnson, 1978). Furthermore, scent trail recruitment facilitates group foraging, which enables bees to monopolize dense patches of highly rewarding resources with sufficient food for many bees (Johnson and Hubbel, 1975;Hassel and Southwood, 1978;Hubbel and Johnson, 1978).…”

Potential mechanisms for the communication of height and distance by a stingless bee, Melipona panamica

“…Such a prolonged reluctance to land seems unlikely given that food competition among stingless bees is intense and time critical. The availability of food sources, not nest sites, appears to limit the density of stingless bee species, and the competition for these resources is usually won by the colony that can most rapidly recruit a large number of foragers (Johnson and Hubbell 1974;Hubbell and Johnson 1978). In the removal experiments testing the communication of distance inside the nest, could more newcomers have arrived at the training feeder because it was located at the same distance as natural food sources?…”

Variation in daily flight activity and foraging patterns in colonies of uruçu - Melipona scutellaris Latreille (Apidae, Meliponini)

“…The immediate needs of the colony, internal conditions such as the quantity of pollen, honey or resin stored and reproductive phases may further define what resources are collected and to what intensity. Competition for floral resources by coexisting highly eusocial species was thought to play a major role in determining foraging behaviour patterns in Meliponini (HUBBELL & JOHNSON 1977, 1978, ROUBIK 1980. ROUBIK (1989) emphasises that bee foraging patterns are determined both by extrinsic and intrinsic variables that vary among species.…”