Surface Temperature and Heat Transfer between Body Regions of Africanized Honeybees (Apis mellifera L.) in Hives under Sun and Shade Conditions in the Northeastern Semi-arid Region of Brazil

Abstract

This work was done at the experimental station of the Federal Rural University of the Semi-arid Region (UFERSA) in Mossoró, Brazil. This work aimed to evaluate the surface temperature of the bees and heat transfer between body regions of Africanized honeybees (Apis mellifera L.) in hives under sun and shade conditions in the northeastern semi-arid region of Brazil. Twelve colonies of Africanized honeybees housed in Langstroth hives were used. The body surface temperature of the bees was measured using a mini infrared thermometer (Fluke model 62). The climatological data were obtained through a meteorological station. The comparison of means was performed by the Tukey-Kramer test (p < 0.01), and data analysis using the Statistical Analysis System software. The body temperatures of the bees are not homogeneous and fluctuate throughout the day, in accordance with the environmental variations. The temperature of the thorax is generally higher, followed by the head and abdomen. The head and the abdomen are parts of the body for which the excess temperature of the thorax is transferred, with the head being the main one. The bees that were in the shade, managed to keep their body temperatures at relatively normal levels, while the bees that were in the sun, had a considered increase of its surface body temperatures higher than 2 °C, being necessary the activation of mechanisms of heat loss, and consequently there is a deviation of energy that could be used for other activities within the colony.

Survey on the types of nesting of Africanized honeybees in urban areas of semiarid regions and rationalization of swarm capture for the benefit of the community

“…Another important aspect is the climate of this study area, characterized by very high temperatures, which hamper the thermal homeostasis of the colonies and cause physiological disturbances in the bees (Domingos & Gonçalves, 2014;Domingos, Sombra, Santos, Gramacho, & Gonçalves, 2018). Africanized bees swarmed more when the environmental conditions in the region are mild.…”

“…Moreover, unlike the exposed swarms, swarms settled in cavities may have benefited from the reduction of energy expenditure to achieve thermal control of the nest area, managing to maintain the thermal homeostasis of the colony more easily, as reported for swarms of A. mellifera nested in cavities (Foss, 2015;Lipinski, 2019). When bees manage to save time and energy in the thermoregulatory processes of the colony, the development and production parameters significantly improve as in these cases, more energy will be available for other tasks such as foraging, thus increasing the productive and expansion capacity of the swarms (Lopes et al, 2011;Santos et al, 2017;Domingos et al, 2018).…”