Читать книгу Honey Bee Medicine for the Veterinary Practitioner - Группа авторов - Страница 78

Honey bees are heterothermic, meaning their individual temperature varies with the outside environment, yet they can also regulate body temperature via endothermic activity (Stabentheiner et al. 2010; Vidal‐Naquet 2015). In addition, honey bee larvae and pupae have a low metabolic rate and cannot maintain thermal constancy in a changing environment; therefore, the brood are strongly dependent upon nest temperature regulation for development (Stabentheiner et al. 2010; Kronenberg and Heller 1982). Fortunately, the social organization of the honey bee hive facilitates colony level homeostasis including the migration activity of the worker bees within the nest and various bee behaviors. Other factors including the size and insulating properties of the nest also affect colony thermoregulation. During the winter, when cooling of the colony occurs, a portion of the worker bees (those older than two days) produce heat by movement of thoracic flight muscles while other nest mates (less than two days old) remain ectothermic (Stabentheiner et al. 2010). Such heat conduction among bees provides effective heat transfer and helps maintain the brood nest temperature in a precise range of 32–36 °C for normal development. Similarly, various strategies are used by social honey bees to cool the nest when the temperature becomes too high, and temperatures above 36 °C are reported to damage brood and negatively affect development (Vidal‐Naquet 2015; Kronenberg and Heller 1982). Cooling of the nest cavity in warm conditions may occur via several mechanisms including dispersal of bees away from the brood, hive ventilation by worker bees fanning their wings or evaporative cooling using water at the hive entrance or within the colony (Winston 1987).