Abstract
Insects react rapidly to environmental change: for example, regional extinction rates of European butterflies have exceeded those of i;-':« |||;| birds and higher plants by an order of magnitude in recent decades. We have also shown that butterflies are accurate indicators of W,\ Ilii change in less conspicuous invertebrate taxa, including functionally important keystone insects such as ants. In theory, ensembles of |S;i jg j closely interacting species are most vulnerable to change as survival depends on the persistence of multiple group members: thus in |! ! ||Jij practice, the greatest recorded declines among butterflies were by the many species that also depend on ants (myrmecophiles). [Hi I I I Here we propose to measure the combined impacts of human-induced changes in climate and habitat (area, isolation, patch quality) fcfj ;??;! on some of Europe's most specialised and threatened grassland myrmecophiles by studying their local adaptations, changing niches \M !||| and different needs across a gradient of local climates from the Mediterranean (lat 42 degrees) to the North/Baltic seas (lat 55 [a:;] degrees). We will model the processes that constrain each system's (meta-)populations, and predict the impacts of future scenarios IS) of land-use, climate and socio-economic change in different regions. We will make new model predictions about how to mitigate the fftjj harmful impacts of multiple drivers on biodiversity, and we will test our recommendations using existing large scale habitat \M manipulations. Finally, we will draw general conclusions about the changing needs of myrmecophiles (c.100,000 spp globally, f; 3 including a disproportionate number of Red Book species) and of non myrmecophilous butterflies, in the latter case by comparing our K<i model predictions with patterns of recorded change in all (UK) or representative (European) species across the climatic gradient, [H using national and European time series and atlas datasets available to the consortium.
Sweden