Traditional prescribed burning of coastal heathland provides niches for xerophilous and sun-loving beetles

Abstract

In Western Norway, farmers have traditionally used fire as a management tool in coastal heathlands to enhance the fodder quality for livestock. Rotational prescribed burning increases landscape heterogeneity by creating a mosaic of different regeneration stages of heather. Ground beetle (Coleoptera: Carabidae) responses to fire in traditionally managed coastal heathland have already been studied, but less is known about other beetle groups in this system. We compared the beetle activity between patches of mature and recently burnt heath, by looking at diversity indices, species composition and ecological preferences and traits. Contrary to previous studies, we did not find an increase in beta diversity after disturbance, but we found that prescribed burning offers micro-environmental conditions which enhanced the activity of sun-loving and xerophilous species. We also identified new indicator species for both mature and pioneer heath in five beetle families: Carabidae, Staphylinidae, Curculionidae, Leiodidae, and Scirtidae. Rotational prescribed burning was confirmed to be an efficient conservation tool for specialists without affecting the overall diversity of the site. We recommend the use of several taxa, ecological preferences and traits to assess the impact of prescribed burning and to monitor the condition of traditionally managed coastal heathlands.