No effect of lack of wood for acorn ant colonies development

Abstract

Acorn ants mostly inhabit cavities in fallen twigs and hollow acorns. Such places, e.g., dead wood, provide an attractive living resource for many groups of microorganisms, like fungi and bacteria, which can be important for ants. However, during experiments in laboratories, acorn ant colonies are typically kept without dead wood. During laboratory experiments, the preferences of the ant Temnothorax crassispinus for nest sites with pieces of dead wood were checked, and whether the presence of such wood influenced productivity. In binary choice tests, colonies had to choose a nest site when presented with two potential nest sites, one empty, or two cavities with different contents. The ant colonies preferred nest cavities with pieces of dead wood versus empty nest cavities. When cavities were filled with pieces of wood or with pieces of wood previously sterilized (72 hours, 70°C), colonies preferred the unsterilized zones. During a three-month laboratory experiment, colonies were kept in the Petri dishes containing pieces of dead wood, containing “sterilised” pieces of dead wood, or without access to wood. In the experiment, no influence was discovered on the availability of dead wood in either colony growth or colony per capita productivity. Thus, the ants prefer cavities with pieces of wood, but the lack of availability of dead wood during a multi-month experiment has no influence on life history parameters.