The performance of models relating species' geographical distributions to climate is independent of trophic level

Species' climate 'envelope' models are widely used to evaluate potential climate change impacts upon species and biodiversity. Previous studies have used a variety of methods to fit models making it difficult to assess relative model performance for different taxonomic groups, life forms or trophic levels. Here we use the same climatic data and modelling approach for 306 European species representing three major taxa (higher plants, insects and birds), and including species of different life form and from four trophic levels. Goodness-of-fit measures showed that useful models were fitted for >96% of species, and that model performance was related neither to major taxonomic group nor to trophic level. These results confirm that such climate envelope models provide the best approach currently available for evaluating reliably the potential impacts of future climate change upon biodiversity

Decline of Corn Buntings Emberiza calandra on east Scottish study areas in 1989-2007

Capsule Adult numbers on many study areas fluctuated from year to year, but overall showed a large decline, down to extinction on most areas. Aims To measure changes in summer numbers of adult Corn Buntings in a large sample of study areas holding discrete localized populations. Methods Singing cocks and hens paired with them were counted in early summer at 30 study areas on farmland from south Angus to central Aberdeenshire. Sixteen populations occurring throughout 1989-95 were called 'groups'. Counts also included 16 cases where a new 'offshoot' appeared in late May or the start of June, not having been seen earlier in that spring or in the previous winter or summer. Results Following relative stability in 1989-95, large declines occurred in 1995-96, 1998-99 and 2003-04, and decreases far outweighed occasional increases between consecutive summers. The numbers of established groups, new offshoots, and older offshoots all declined with the year. Although containing one to nine founding pairs, new offshoots became extinct later, in six cases after one summer. No new offshoot was seen after 1995. Conclusions Although 22 study areas held birds in 1989 and 25 in 1990, this fell to 10 in 1999, seven in 2005, and four in 2007 (the only areas that held birds in all years). On all areas combined, cock numbers fell by 83% between 1989 and 2007. Targeted implementation of appropriate agri-environment measures is urgently needed to halt and reverse such declines, a challenge made all the greater within the last year by rising grain prices, delays to the introduction of new measures, and abolition of EU 'set-aside' as a means for providing food and nesting habitat