Size-related mortality during overwintering in cavity-nesting ant colonies (Hymenoptera: Formicidae)

• Main Author: Sławomir MITRUS
• Format: Article
• Language: English
• Published: Institute of Entomology, Biology Centre, Czech Academy of Science 2016-10-01
• Series: European Journal of Entomology
• Subjects: hymenoptera; formicidae; temnothorax crassispinus; survival rate; snow cover; social insects; overwintering
• Online Access: https://www.eje.cz/artkey/eje-201601-0070_Size-related_mortality_during_overwintering_in_cavity-nesting_ant_colonies_Hymenoptera_Formicidae.php

The ongoing process of climate change will result in higher temperatures during winter and therefore might increase the survival of overwintering invertebrates. However, the process may also lead to a reduction in snow cover and expose overwintering invertebrates to lower temperatures, which could result in higher mortality. During a field experiment, I investigated the effects of a reduction in snow cover on the survival of the ant Temnothorax crassispinus, which overwinters in nests located on the ground. Ant colonies differed in the survival rate of the workers in the experimental (from which snow cover was removed) and control group. In the control group, the survival rate was unrelated to colony size. However, in the experimental group, from which snow was removed after each heavy snowfall, worker survival was lower in small colonies. Such colony size related mortality may affect the fusion of colonies before winter.