Climate envelope, life history traits and the resilience of birds facing global change FRE ´ DE ´ RIC JIGUET* w , ANNE-SOPHIE GADOT * , ROMAIN JULLIARD *, STUART E. NEWSON zw and D E N I S C O U V E T * *Centre de Recherches sur la Biologie des Populations d’Oiseaux, UMR 5173 Conservation des Espe `ces, Restauration et Suivi des Populations, CP 51, Muse ´um National d’Histoire Naturelle, 55 rue Buffon, F-75005 Paris, France, wEuropean Bird Census Council, c/o The Royal Society for the Protection of Birds, The Lodge, Sandy, Bedfordshire SG19 2DL, UK, zBritish Trust for Ornithology, The Nunnery, Thetford, Norfolk IP24 2PU, UK Abstract Few studies have examined how life history traits and the climate envelope influence the ability of species to respond to climate change and habitat degradation. In this study, we test whether 18 species-specific variables, related to the climate envelope, ecological envelope and life history, could predict recent population trends (over 17 years) of 71 common breeding bird species in France. Habitat specialists were declining at a much higher rate than generalists, a sign that habitat quality is decreasing globally. The lower the thermal maximum (temperature at the hot edge of the climate envelope), the more negative are the population trends and the less tolerant these species are climate warming, regardless of the thermal range over which these species occur. The life history trait ‘the number of broods per year’ was positively related to recent trends, suggesting that single-brooded species might be more sensitive to advances in food peak due to climate change, as it increases the risk of mistiming their single-breeding event. Annual fecundity explained long-term declines, as it is a good proxy for most other demographic rates, with shorter-lived species being more sensitive to global change: individuals of species with higher fecundity might have too short a life to learn to adapt to directional changes in their environment. Finally, there was evidence that natal dispersal was a predictor of recent trends, with species with high natal dispersal experiencing smaller population declines than species with low natal dispersal. This is expected if the higher the natal dispersal, the larger the ability to shift spatially when facing changes in local habitat or climate, in order to track optimal conditions and adapt to global change. Identifying decline-promoting factors allow us to infer mechanisms responsible for observed declines in wild bird populations facing global change, and by doing so allow for a more pre-emptive approach to conservation planning. Keywords: annual fecundity, broad-scale monitoring, brood number, climate warming, habitat specialist, natal dispersal, population trend, thermal maximum Received 24 October 2006 and accepted 9 February 2007 Introduction Climate change and large scale habitat degradation are known to reduce biodiversity (Donald et al., 2001; Walther et al., 2002). Climate change has already been linked to distributional (Parmesan & Yohe, 2003; Thuiller et al., 2005), elevational (Wilson et al., 2005), ecological (Davies et al., 2006) and phenological (Crick & Sparks, 1999; Jonze ´n et al., 2006; Menzel et al., 2006) shifts. Habitat specialists of a number of taxa have been recorded as suffering from habitat degradation (plants: Fischer & Sto ¨ cklin, 1997; Rooney et al., 2004; butterflies: Warren et al., 2001; carabid beetles: Kotze & Ohara, 2003; mammals: Fisher et al., 2003; bumblebees: Goulson et al., 2004; coral reef fish: Munday 2004; birds: Julliard et al., 2004), leading to functional and/or taxonomic biotic homogenization (McKinney & Lockwood, 1999; Olden et al., 2004). Candidate traits that might be associated Correspondence: Fre ´de ´ric Jiguet, CRBPO, 55 rue Buffon, F-75005 Paris, France, tel. 133 1 40 79 30 80, fax 133 1 40 79 38 35, e-mail: fjiguet@mnhn.fr Global Change Biology (2007) 13, 1672–1684, doi: 10.1111/j.1365-2486.2007.01386.x r 2007 The Authors 1672 Journal compilation r 2007 Blackwell Publishing Ltd