Species richness and temporal partitioning in the beetle fauna of oak trees (Quercus robur L.) in Richmond Park, UK NIGEL E. STORK 1 and PETER M. HAMMOND 2 1 Griffith School of Environment, Griffith University, Nathan Campus, Nathan, Qld, Australia and 2 Department of Entomology, The Natural History Museum, London, UK Abstract. 1. Species richness, abundance, body size, biomass, guild structure and temporal partitioning were examined in samples of 150 beetle species from oaks (Quercus robur L.) in southern Britain. 2. Abundance, species richness and biomass were highest in late June when leaves are in full flush, similar through much of the year for oak specialist beetle species, but were highest in July for generalists. Body size did not appear to vary significantly during the sampling period. 3. Temporal partitioning of feeding guilds was evident; predators and herbivores, peaked earlier in May–June, and fungivores and scavengers peaked in July–August. 4. Groups of closely related species, in Carabidae, Cantharidae and Curculionidae, often had similar seasonal patterns suggesting that temporal variation in both overall species richness and abundance for different guilds may be driven by resource avail- ability rather than competition between closely related species. 5. Multidimensional scaling ordination shows an almost circular pattern in the beetle community underpinned by the most abundant species occurring throughout the year; vector analysis indicates that as temperatures increase and food resources become available, other species become abundant and influence patterns of similarity. 6. These patterns are also influenced by species that (i) have life cycles of 2 or more years, (ii) move between the ground, tree trunks and the canopy during the year and (iii) move from other tree species to oaks as these tree species lose their leaves earlier in Autumn. 7. The hypothesis that temporal patterns for invertebrate species in temperate trees are more coordinated than those in tropical trees is not supported. Key words. Beetles, Coleoptera, oak trees, Quercus robur, seasonality, species richness, temporal partitioning. Introduction The immense diversity of invertebrates, particularly insects, in the crowns of both tropical and temperate trees is a remarkable ecological phenomenon, and how so many species can coexist is still not adequately explained by ecological theory. One reason that has been suggested for high species richness, particularly for tropical organisms, is the temporal and spatial partitioning of resources (Schoener, 1974a,b). Insects with similar ecological traits may coexist by being abundant or active at different times of the day or year, thereby avoiding competition (Wolda & Fisk, 1981; Tylianakis et al., 2005). Other species may be using resources in a spatially discrete manner (e.g. Stork et al., 2001). Extensive study of temperate arthropods over the last couple of centuries, particularly in Western Europe, has resulted in a rich knowledge of the biology for many species (e.g. Bale, 1981) and of forest insect ecology in general (e.g. Watt et al., 1997; Speight et al., 1999). For many forest species, particularly herbi- vores, much of their life cycle is so well known that when they may appear as adults are largely predictable. The ecological value in studying communities of British insects is that we do not need to resort to the use of ‘morphospecies’ and assumed Correspondence: Nigel E. Stork, Griffith School of Environ- ment, Griffith University, Nathan Campus, 170 Kessels Road, Nathan, Qld 4111, Australia. E-mail: nigel.stork@griffith.edu.au Insect Conservation and Diversity (2012) doi: 10.1111/j.1752-4598.2012.00188.x Ó 2012 The Authors Insect Conservation and Diversity Ó 2012 The Royal Entomological Society 1