The effects of wildfire on Spheciformes wasp community structure: the importance of local habitat conditions

Abstract

Changes of the structure of a community of Spheciformes wasps (Hymenoptera: Apoidea) along a 15 year recovery gradient after wildfires in a Mediterranean agroecosystem are reported and analysed. The species that contribute to determining the structure, change in dominance amongst the most abundant species, and variation in guild structure of the community with the passage of time since fire, as well as the environmental variables contributing to the structure of the community are also analyzed. Mediterranean Spheciformes communities are highly resistant to fire. The sampling year, representative of different climate conditions, and the time since the fire, were the main variables which affected community variation local conditions of the habitat was more important than time since fire in determining community. Local conditions; presence of trophic resources, nesting sites, and presence of prey for feeding the larvae, depended on climatological conditions and the time since fire. Variations were detected in the dominance values of the most abundant species, together with displacements among species within the same genus, as a function of the local conditions, the existing resources, and the time since the wildfire. Therefore, change in community structure cannot be attributed solely to the effect of the fire, as both climatic and environmental conditions contribute to community structure.