Microhabitat selection in the potentially endangered wolf spider Donacosa merlini (Araneae, Lycosidae): implications for spider conservation

Abstract

Habitat quality affects many components of animal fitness and animals are expected to be distributed in the space accordingly. Mismatch between habitat preferences and fitness may relate to scale-dependent effects and trade-offs between costs and benefits of moving to high-quality habitats. We investigated the effects of habitat quality and habitat selection in Donacosa merlini Alderweireldt and Jocqué, 1991, a burrowing wolf spider included in the Spanish Invertebrates Red Data Book. Particularly, we compared burrow size and density and analysed the relationship between burrow presence and vegetation at two different scales. At a regional scale, we found strong differences in burrow size and density. Burrow density affected burrow aggregation, which was utmost under mean densities. At both spatial scales, burrows were found at relatively clear (or low-covered) patches, as scrubs were lower and nearest vegetation was farther from burrows than randomly expected. Our results suggest habitat selection and effects of habitat quality on the life history of D. merlini. In spite of the recent expansion of the species distribution area, our data support the need for suitable habitat management programs. Information about ecological requirements is paramount to correctly assess spider conservation status. This topic has received little attention in spite of the diversity and the relevance of spider ecological roles.