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Climate change is increasingly altering the composition of ecological communities, in combination with other environmental pressures such as high-intensity land use. Pressures are expected to interact in their effects, but the extent to which intensive human land use constrains community responses to climate change is currently unclear. A generic indicator of climate change impact, the community temperature index (CTI), has previously been used to suggest that both bird and butterflies are successfully ‘tracking’ climate change. Here, we assessed community changes at over 600 English bird or butterfly monitoring sites over three decades and tested how the surrounding land has influenced these changes. We partitioned community changes into warm- and cold-associated assemblages and found that English bird communities have not reorganized successfully in response to climate change. CTI increases for birds are primarily attributable to the loss of cold-associated species, whilst for butterflies, warm-associated species have tended to increase. Importantly, the area of intensively managed land use around monitoring sites appears to influence these community changes, with large extents of intensively managed land limiting ‘adaptive’ community reorganization in response to climate change. Specifically, high-intensity land use appears to exacerbate declines in cold-adapted bird and butterfly species, and prevent increases in warm-associated birds. This has broad implications for managing landscapes to promote climate change adaptation.

It is important for conservationists to be able to assess the risks that climate change poses to species, in order to inform decision making. Using standardised and repeatable methods, we present a national-scale assessment of the risks of range loss and opportunities for range expansion that climate change could pose for over 3000 plants and animals. Species were selected by their occurrence in England, the primary focus of the study, but climate change impacts were assessed across Great Britain, widening their geographical relevance. A basic risk assessment that compared projected future changes in potential range with recently observed changes classified 21% of species as being at high risk and 6% at medium risk of range loss under a B1 climate change scenario. A greater number of species were classified as having a medium (16%) or high (38%) opportunity to potentially expand their distribution. A more comprehensive assessment, incorporating additional ecological information, including potentially confounding and exacerbating factors (e.g. dispersal, habitat availability and other constraints), was applied to 402 species, of which 35% were at risk of range loss and 42% may expand their range extent. This study covers a temperate region with a significant proportion of species at their poleward range limit; the balance of risks and opportunities from climate change may be different elsewhere. The outcome of both risk assessments varied between taxonomic groups, with bryophytes and vascular plants containing the greatest proportion of species at risk from climate change. Upland habitats contained more species at risk than other habitats. Whilst the overall pattern was clear, confidence was generally low for individual assessments, with the exception of well-studied taxa such as birds. In response to climate change, nature conservation needs to plan for changing species distributions and an uncertain future.