The use of cork in the thermoregulation of the hive: an innovation attempt to enhance non-wood products and beekeeping in Mediterranean forests

Hive thermoregulation is fundamental for the normal development of bee colonies and, consequently, hive productivity and honey bee health. External conditions mainly affect the walls of the hive. Therefore, hive construction materials and thermal conductivity features can influence its thermoregulation efficiency. The present trial made a comparison of experimental hives (modified Dadant-Blatt of 10 frames) made with cork as thermal insulator and conventional hives made entirely with firwood to evaluate their effects on thermoregulation of Apis mellifera ligustica colonies in Northwerstern Sardinia (Italy). The cork-modified beehives consisted of common conventional beehives modified by replacing the wooden walls with cork walls (pressed cork), whereas the control beehives (wooden hives) consisted of standard Dadant Blatt beehives entirely made of firwood. Environmental (especially nest internal temperature) parameters were assessed periodically. The daily temperature pattern of cork-modified beehives was more regular than that of control beehives. In addition, bees had a more efficient winter thermoregulation in cork-modified beehives compared with control hives.