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We review the observed and potential effects of climate change on native fauna of forests in northeastern North America by focusing on mammals, birds, amphibians, and insects. Our assessment is placed in the context of recent regional-scale climate projections. Climate change, particularly in recent decades, has affected the distribution and abundance of numerous wildlife species. Warming temperatures, alterations to precipitation regimes, seasonality, and climatic extremes are projected to affect species directly or indirectly in each of the focal taxa. Greatest climate change will occur during winter, and the survival of winter-active species as well as the survival, distribution, and abundance of hibernating mammals, amphibians, resident birds, and diapausing insects may be altered. Even under low emissions scenarios, effects on native fauna may be profound, affecting iconic species, endangered species, and species that provide economically valuable services, such as pollination and regulation of insect populations. However, much research that is essential to assessing the effects of climate change on the native fauna of northeastern forests remains to be done. Research that reveals causal mechanisms and relates these findings to population and community level processes will be most valuable. Nous passons en revue les effets observes et potentiels des changements climatiques sur la faune indigene des forets du nord-est de l'Amerique du Nord en mettant l'accent sur les mammiferes, les oiseaux, les amphibiens et les insectes. Notre evaluation se situe dans le contexte des recentes projections du climat a l'echelle regionale. Les changements climatiques, particulierement au cours des recentes decennies, ont affecte la distribution et l' abondance de plusieurs especes sauvages. On prevoit que le rechauffement des temperatures, la modification des regimes de precipitation, la saisonnalite et les phenomenes climatiques extremes affecteront les especes fauniques directement ou indirectement dans chacun des taxons vises. Les changements climatiques les plus draconiens surviendront durant l'hiver et la survie, la distribution ainsi que l' abondance des mammiferes qui hibernent, des amphibiens, des oiseaux qui ne migrent pas et des insectes qui entrent en diapause pourraient etre affectees. Memes selon les scenarios qui prevoient des emissions faibles, les effets sur la faune indigene pourraient etre dramatiques et affecter des especes emblematiques, des especes menacees et des especes qui procurent des services economiques precieux tels que la pollinisation et la regulation des populations d'insectes. Cependant, beaucoup de travaux de recherche essentiels pour evaluer les effets des changements climatiques sur la faune indigene des forets du nord-est restent a faire. Les travaux de recherche qui portent sur les mecanismes causals et relient ces resultats aux processus qui se deroulent a l'echelle de la communaute et de la population seront les plus utiles., [Traduit par la Redaction] Introduction Climate affects the native fauna of forests in northeastern North America at all levels of organization, from the physiological (e.g., Portner 2002) to the landscape [...]

Although long-distance migratory songbirds are widely believed to be at risk from warming temperature trends, species capable of attempting more than one brood in a breeding season could benefit from extended breeding seasons in warmer springs. To evaluate local and global factors affecting population dynamics of the black-throated blue warbler ( Setophaga caerulescens), a double-brooded long-distance migrant, we used Pradel models to analyze 25 years of mark-recapture data collected in New Hampshire, USA. We assessed the effects of spring temperature (local weather) and the El Niño Southern Oscillation index (a global climate cycle), as well as predator abundance, insect biomass, and local conspecific density on population growth in the subsequent year. Local and global climatic conditions affected warbler populations in different ways. We found that warbler population growth was lower following El Niño years (which have been linked to poor survival in the wintering grounds and low fledging weights in the breeding grounds) than La Niña years. At a local scale, populations increased following years with warm springs and abundant late-season food, but were unaffected by spring temperature following years when food was scarce. These results indicate that the warming temperature trends might have a positive effect on recruitment and population growth of black-throated blue warblers if food abundance is sustained in breeding areas. In contrast, potential intensification of future El Niño events could negatively impact vital rates and populations of this species. [ABSTRACT FROM AUTHOR]

Nestbox provision is a technique used to increase nest-site availability for secondary cavity-nesting birds. However, little is known about the demographic consequences of nestbox provision in different habitat types. To assess how nestbox provision affects the density of hole-nesting birds simultaneously in two contrasting habitats, we compared the breeding density of Great Tits along transects without nestboxes with that in transects where nestboxes were provided. Although the initial density of breeders was considerably higher in the deciduous habitat than in the coniferous habitat, provision of nestboxes increased density by a similar number of additional pairs in each habitat type. Thus, the provision of nestboxes in managed coniferous forests may be as effective in increasing the breeding opportunities of cavity nesters as in deciduous stands. Moreover, previous research showed that pairs in deciduous habitat with nestboxes have consistently lower breeding success than those in coniferous habitat with nestboxes. It is possible that the addition of nestboxes in the preferred habitat increased density to such an extent that density-dependent effects became apparent. [ABSTRACT FROM AUTHOR]