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MOTIVATION: We undertook large citizen science surveys of bird distributions (atlases) in Britain and Ireland, aimed at quantifying breeding bird distributions on a 20‐year cycle and wintering bird distributions on a c. 30‐year cycle. We use these to generate spatially referenced information on apparent changes in bird distributions over c. 40 years. MAIN TYPE OF VARIABLE CONTAINED: Detection of breeding and wintering bird species in grid squares during five periods, and changes in detection between periods. The combined distribution dataset contains 1,410,938 records detailing detections of 465 bird species in 3,880 grid cells in different periods. The combined distribution change dataset contains 1,297,791 records describing stability, apparent colonization or apparent extinction of individual species in grid squares between pairs of atlases spanning up to c. 40 years. SPATIAL LOCATION AND GRAIN: Grid squares (10 km × 10 km) containing land throughout Britain, Ireland, the Isle of Man and the Channel Islands. The majority of data are at 10‐km resolution, but data for rare species are summarized at 20‐ or 50‐km resolution to protect sensitive locations. TIME PERIOD: The data represent summarized detection information derived from fieldwork during five periods: the breeding seasons 1968–1972, 1988–1991 and 2008–2011, and the winters 1981/1982–1983/1984 and 2007/2008–2010/2011. MAJOR TAXA STUDIED AND LEVEL OF MEASUREMENT: Birds; their distribution derived from citizen science surveys. SOFTWARE FORMAT: Data are supplied as comma‐separated text files.

In this paper we test whether the morphology and life traits of species (in our case ground beetles of the family Carabidae) can be related to the main underlying axes of environmental variability of their habitats. Sites were selected a priori to maximize two gradients: land use as a general measure of disturbance characterized by an index of land management, and habitat adversity or stress as characterized by elevation and vegetation structure. The underlying environmental axes and the relationships of the morphology and life traits of the species with them were investigated using RLQ analysis, a multivariate ordination method able to relate a species trait table to a site characteristics table by way of a species abundance table. The first environmental axis was highly statistically significant and explained most of the variability. It was strongly negatively related to the intensity of land management, and positively related to increasing elevation and a set of variables reflecting vegetation stress. Two predictions were tested and found to be valid in the studied system: in highly managed lowland sites species were smaller, and the frequency of macropterous species (with better dispersal abilities) was higher. Other traits also showed significant relationships with the main environmental axis: in the intensively managed lowland sites species had broader bodies, longer trochanters, and wider femora (characters associated with plant eaters), were paler in color, overwintered only as adults, bred in spring or autumn, and were active in summer. We conclude that the ground beetle assemblages of the studied sites respond in a similar way to the same underlying environmental factors. This allows the precise definition of functional groups, which can be used to characterize functional diversity and its relationships with changes in land management.

The influence of the interface between different vegetation types on the surface active spider fauna within a grass pasture-coniferous plantation ecotone was sampled by pitfall trapping. Species abundance, richness and diversity relative to pitfall traps were measured along a transect across the ecotone. Spider species were classified into six categories based on their habitat preference and the influence of the non-preferred habitat. The number of individuals trapped progressively decreased from the pasture across the interface to the plantation habitat. Species richness increased by some 72% and diversity by some 141% at the interface. These increases were attributable to both the overlap of pasture and plantation species invading the non-preferred habitat across the interface, and to the presence of species with a preference for the ecotone. The overlap of pasture and plantation species was found to be the larger part of the spider community at the interface, species classed as ecotone accounting for only 25% of the catch at the interface. Distinct spider species assemblages were found in the pasture and plantation habitats, and the interface species composition was more similar to the plantation than to the pasture. The variation in physical and biological characteristics which the interface induces, and their influence on the spider assemblages found, are discussed in relation to other ecotone studies.

Thirteen study sites were selected to cover the dominant vegetation types on the plateaux of three summits in the North Pennines, England. The spider community of these sites were sampled by pitfall trapping between April and October 1991. Several environmental variables were collected for each site, including local topography, soil characteristics and vegetation structure. Multivariate methods were used to classify the sites based on their spider species composition. Canonical correspondence analysis was used to assess the influence of the external factors on the distribution of the species. The results suggest that vegetation density is the major factor influencing spider distribution on the summit plateaux with slope and soil depth also contributing to the variation. Three spider associations for the plateaux are proposed based on their common species composition. Two short Festuca grassland assemblages and a Nardus/Eriophorum spp. assemblage associated with higher vegetation density. The habitat preferences of some species common to the plateaux are discussed in light of the results, and comparisons are made with studies from other upland areas