SEASONAL INFLUENCE ON THE BEHAVIOR OF WORKERS AND ARCHITECTURE OF THE Melipona quadrifasciata COLONY (HYMENOPTERA; APOIDEA; MELIPONINI)

*Corresponding author e-mail: iessycamargo2003@gmail.com Introduction: Melipona quadrifasciata is a tropical eusocial stingless bee. In this species, the workers (sterile females) are responsible for the physical maintenance of the colony. The structure of the nest comprises the regions: 1) brood chamber - in the center of the nest, where the oviposition by the queen (fertile female) occurs. Nurses (young workers) build brood cells. 2) pots region - food storage region, where intermediate age workers - builders - construct pots to store honey and pollen. 3) entrance - consists in a hole, used in the orientation of foragers (old workers) returning from the field and in a tunnel that guarantees constant darkness inside the nest. Methods: In this work, seven colonies of M. quadrifasciata have been eye-inspected, during two years. In each inspection, the regions of the nest were measured and the workers activity registered. To evaluate behavior, ethograms were built. Results/Conclusion: The hive structure shows different proportions and characteristics according to the season. In the end of summer/beginning of autumn, the pots area and the number of pots increase. Their maximum size and number are reached by the end of autumn. These increases are related to the amount of food stored and accumulation of reserves are a form of anticipation for wintertime when flowering is at its lowest level. This anticipation assures the colony survival during winter and it occurred in both years of observation. Foragers activity is low or absent during the same interval. In contrast with the pots area, the brood chamber area is enlargemented during summer and to the increase in size corresponds a addition in oviposition episodes. Even though experiments under controlled environmental conditions will be necessary, the results indicate rhythmic changes in the proportions of the nest’s areas and in the castes’ activity along the year. In addition to variations in the structure, preliminary data indicate the existence of circadian and ultradian components in the daily activity of builders. Their activity pattern is in antiphase with that of foragers. Possibly this is because the population within the colony increases during the dark as foragers remain inside the hive at night. Results allow to demonstrating the existence of an internal temporal organization in the colony of M. quadrifasciata . How much of it is due to endogenous rhythms is not known yet, however ultradian, daily and seasonal components are present both in the activity of the castes and the structure of the colony. Publication History Article published online: 16 June 2026 © 2009. Brazilian Sleep Academy. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/) Thieme Revinter Publicações Ltda. Rua Rego Freitas, 175, loja 1, República, São Paulo, SP, CEP 01220-010, Brazil