Macroecological patterns of spider species richness across Europe

Abstract

We analysed the pattern of covariation of European spider species richness with various environmental variables at different scales. Four layers of perception ranging from single investigation sites to the whole European continent were selected. Species richness was determined using published data from all four scales. Correlation analyses and stepwise multiple linear regression were used to relate richness to topographic, climatic and biotic variables. Up to nine environmental variables were included in the analyses (area, latitude, elevation range, mean annual temperature, local variation in mean annual temperature, mean annual precipitation, mean July temperature, local variation in mean July temperature, plant species richness). At the local and at the continental scale, no significant correlations with surface area were found, whereas at the landscape and regional scale, surface area had a significant positive effect on species richness. Factors that were positively correlated with species richness at both broader scales were plant species richness, elevation range, and specific temperature variables (regional scale: local variation in mean annual, and mean July temperature; continental scale: mean July temperature). Latitude was significantly negatively correlated with the species richness at the continental scale. Multiple models for spider species richness data accounted for up to 77% of the total variance in spider species richness data. Furthermore, multiple models explained variation in plant species richness up to 79% through the variables mean July temperature and elevation range. We conclude that these first continental wide analyses grasp the overall pattern in spider species richness of Europe quite well, although some of the observed patterns are not directly causal. Climatic variables are expected to be among the most important direct factors, although other variables (e.g. elevation range, plant species richness) are important (surrogate) correlates of spider species richness.

Water limitation prevails over energy in European diversity gradients of sheetweb spiders (Araneae: Linyphiidae)

“…In contrast to spiders in general (Finch et al 2008), species richness and diversity of sheetweb spiders showed a hump-shaped relationship to latitude with a maximum at 521N and 591N in country inventories and habitat samples, respectively. This covers the range from northern Germany, Poland and Belarus to southern Norway and Sweden.…”

“…Spider species richness at a continental scale in Europe is negatively correlated with latitude (Finch, Blick, & Schuldt 2008). However, this overall pattern may become quite different when broken down to family level.…”

Large and least isolated fragments preserve habitat specialist spiders best in dry sandy grasslands in Hungary

“…There are several publications in which spiders in different 274 grassland types were studied and stressed that landscape features (habitat connectivity, 275 structural heterogeneity, landscape structure) also played a very important role in species 276 composition and abundance Finch et al 2008 293 These processes jeopardize the survival of most habitat specialist and rare animal and plant 294 species. Therefore, nowadays there is a growing demand for the conservation of the 295 different grassland types.…”

Spider Assemblages across Elevational and Latitudinal Gradients in the Yukon Territory, Canada

“…Latitude tends to be negatively correlated with species richness (e.g., Cushman et al, 1993;Lyons and Willig, 2002;Finch et al, 2008), with some exceptions (e.g., Dixon et al, 1987;Kouki et al, 1994). Studies of elevation, which mimic environmental changes associated with latitude at a more abrupt spatiotemporal scale (Hodkinson, 2005), tend to show decreases in diversity with increasing elevation, but these responses are not often linear (Rahbek, 1995).…”