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Colony multiplication of the neotropical stingless bee Tetragonisca angustula started with the finding of a new nesting site by scout bees, followed by the cleaning of the cavity. Cerumen was flown in from the mother colony for the sealing of crevices and the construction of an entrance tube. Major investment of the mother colony in the daughter nest was in workers and cerumen. Almost negligible amounts of pollen were transported from the mother colony after arrival of the gyne in the founding colony. Small quantities of honey were transferred as well. Workers from the daughter nest foraged actively for pollen. Some 500 to 1000 workers entered in the daughter nest, following the virgin queen. This is only a relatively small proportion of the population of the mother colony. Two to four days after the nuptial flight the young queen started egg-laying, and storage pots, mainly filled with honey and some pollen were encountered. In the mother nest, ample pollen and honey stores were present during the months preceding the swarming process. Shortly before swarming took place brood (and adult) populations were 20 to 50% higher than in the other non-swarming colonies, whereas the production of royal cells and males was not different. Data were compared with those got in literature.

Summary.Male production was studied in four queenright M. favosa colonies by permanent and long duration observation of egg-laying and subsequent bee emergence. Workers produced males in all colonies; they produced 94.5% of all males.

For Melipona fasciata, M. beecheii, M. favosa and Tetragonisca angustula we found distinct intergeneric differences in foraging activity patterns. The Melipona species had a longer daily foraging activity period than T. angustula. Pollen foraging patterns of the Melipona species were different from that of T. angustula: Melipona collect pollen earlier in the day. In an experimental habitat without competitors, Melipona favosa did not collect pollen very early in the day.Individually marked returning foragers demonstrated in the course of the day distinct differences in nature and frequency of interactions with nest mates. Individual foraging flight frequency was lower and the intranidal transfer of nectar was delayed when syrup of a lower concentration was offered.The regulation of daily foraging activity patterns and the nectar foraging behaviour of individual worker bees are discussed.

-In many stingless bee species, laying workers oviposit trophic eggs that serve as a component of the queen's diet. Workers of some species also lay reproductive worker eggs that give rise to males. Maleproducing workers can occur in queenright colonies. We studied male production by workers of Melipona favosa. In six colonies monitored under field conditions, we observed that males emerged during distinct "Male Emerging Periods". Subsequently, we studied the laying of male eggs in laboratory observation hives with the use of video. We found that laying workers oviposited reproductive eggs in distinct "Reproductive Laying Worker Periods" and that this was followed by the clumped mergence of males afterwards. Behaviours of laying workers and of the ovipositing queen are preliminarily described.Melipona / laying worker / male production / reproductive eggs / trophic eggs

Abstract. To study the reproductive potential of workers in the stingless bee Trigona (Tetragonisca) angustula Illiger (Apidae, Meliponinae), we examined the morphological quality of their eggs. Worker‐eggs were all placed on the inside of the upper wall of brood cells. Normally, such eggs are consumed by the queen and are therefore referred to as trophic. The provisioning and oviposition processes in queenright colonies are characterized by the occurrence of circular aggregations of workers, ‘rosettes’, around the broodcell opening immediately after the release of a worker‐egg. The ovaries of 35% of these rosette workers contained mature, chorionated eggs. In a single worker ovary, always only one mature egg was found. Some of the eggs, dissected from the ovarioles, showed a reticulate chorion pattern. Worker‐eggs which lacked this pattern were significantly bigger than patterned eggs. Scanning electron micrographs revealed that the patterned worker‐eggs are similar in appearance to queen‐eggs. After a worker‐egg had been removed experimentally from a broodcell, the same cell could be oviposited by a worker again. Light microscopic analysis revealed that all these worker‐eggs lacked the reticulate chorion pattern and were very similar in their morphology. In a colony without a laying queen workers laid eggs which had a reticulate pattern on the chorion. Since these eggs developed into males, we assume that the pattern on the chorion is characteristic for reproductive eggs. We also assume that the queen prevents the release of reproductive eggs by the workers. However, she does not inhibit the development of this type of egg.

This paper is the report of a long-duration study of the production of gynes and males in Melipona stingless bees in Trinidad and Tobago, including a behavioural study of laying workers. In 167 brood samples (16342 pupae) of M. favosa, taken from 78 colonies in the natural environment over the years 1993 -2001, workers represented 78.4% and males represented 17.3%. Gynes represented 5.1% of all female brood. Gyne proportion never exceeded 22.5%. Gynes were found to be common throughout the year. Like the gynes, males were present all year, but their occurrence varied over the months. Males were most common in the months of July and August. At the colony level male occurrence in the brood was characterized by very high values (maximum 74.2%), next to a frequent complete absence (in 26.5% of all samples). The finding of bout-like production of males at the colony level is supported by the observations on reproductive worker behaviour. The colonies appeared to be in different phases of male production. When male producing laying workers were present, they competed heavily for egg-laying opportunities. Various behaviours of laying workers and the queen are described and interpreted on the basis of reproductive competition and kin conflict theories. From these results, we conclude that in M. favosa, workers have a distinct influence on reproduction, including the production of gynes and males.

Since its first contact with Apis mellifera, the population dynamics of the parasitic mite Varroa destructor varies from one region to another. In many regions of the world, apiculture has come to depend on the use of acaricides, because of the extensive damage caused by varroa to bee colonies. At present, the mite is considered to contribute to the recent decline of honey bee colonies in North America and Europe. Because in tropical climates worker brood rearing and varroa reproduction occurs all year round, it could be expected that here the impact of the parasite will be even more devastating. Yet, this has not been the case in tropical areas of South America. In Brazil, varroa was introduced more than 30 years ago and got established at low levels of infestation, without causing apparent damage to apiculture with Africanized honey bees (AHB). The tolerance of AHB to varroa is apparently attributable, at least in part, to resistance in the bees. The low fertility of this parasite in Africanized worker brood and the grooming and hygienic behavior of the bees are referred as important factors in keeping mite infestation low in the colonies. It has also been suggested that the type of mite influences the level of tolerance in a honey bee population. The Korea haplotype is predominant in unbalanced host-parasite systems, as exist in Europe, whereas in stable systems, as in Brazil, the Japan haplotype used to predominate. However, the patterns of varroa genetic variation have changed in Brazil. All recently sampled mites were of the Korea haplotype, regardless whether the mites had reproduced or not. The fertile mites on AHB in Brazil significantly increased from 56% in the 1980s to 86% in recent years. Nevertheless, despite the increased fertility, no increase in mite infestation rates in the colonies has been detected so far. A comprehensive literature review of varroa reproduction data, focusing on fertility and production of viable female mites, was conducted to provide insight into the Africanized bee host-parasite relationship.