Morphological constraints on changing avian migration phenology

Abstract

Many organisms at northern latitudes have responded to climate warming by advancing their spring phenology. Birds are known to show earlier timing of spring migration and reproduction in response to warmer springs. However, species show heterogeneous phenological responses to climate warming, with those that have not advanced or have delayed migration phenology experiencing population declines. Although some traits (such as migration distance) partly explain heterogeneity in phenological responses, the factors affecting interspecies differences in the responsiveness to climate warming have yet to be fully explored. In this comparative study, we investigate whether variation in wing aspect ratio (reflecting relative wing narrowness), an ecomorphological trait that is strongly associated with flight efficiency and migratory behaviour, affects the ability to advance timing of spring migration during 1960-2006 in a set of 80 European migratory bird species. Species with larger aspect ratio (longer and narrower wings) showed smaller advancement of timing of spring migration compared to species with smaller aspect ratio (shorter and wider wings) while controlling for phylogeny, migration distance and other life-history traits. In turn, migration distance positively predicted aspect ratio across species. Hence, species that are better adapted to migration appear to be more constrained in responding phenologically to rapid climate warming by advancing timing of spring migration. Our findings corroborate the idea that aspect ratio is a major evolutionary correlate of migration, and suggest that selection for energetically efficient flights, as reflected by high aspect ratio, may hinder phenotypically plastic/microevolutionary adjustments of migration phenology to ongoing climatic changes.

Habitat‐ and species‐mediated short‐ and long‐term distributional changes in waterbird abundance linked to variation in European winter weather

“…This, coupled with the increase in winter mildness (and continuation of a positive phase in NAO) predicted under many climate change scenarios (Visbeck, Hurrell, Polvani, & Cullen, ; Intergovernmental Panel on Climate Change (IPCC), ), suggests that full shifts of wintering ranges (sensu Elmberg et al., ) of many waterbird species are likely to occur in the future. However, our results also suggest that shifts may not be driven solely by weather conditions but will occur in synergy with ecological and life‐history traits (Dalby et al., ; MacLean & Beissinger, ; Møller et al., ), changes in species wintering habitats (e.g., restoration of wetlands and novel food sources due to invasive species) and in relation to species breeding distributions.…”

“…Accumulating evidence shows that changes in climatic conditions have become a major threat to the maintenance of biodiversity (Parmesan & Yohe, ; Thomas & Williamson, ) and responses to such changes are already apparent among many taxa (Amano et al., ; Chen, Hill, Ohlemüller, Roy, & Thomas, ; Hughes, ; Knudsen et al., ; Parmesan, ). Common responses to climate change are, for example, adjustments to timing of phenological events, such as flowering (Frei, Ghazoul, Matter, Heggli, & Pluess, ; Menzel et al., ) or migration time (Kelly et al., ; Møller, Rubolini, & Lehikoinen, ; Møller, Rubolini, & Saino, ) or changes in distribution (Amano et al., ; Thomas et al., ).…”

Shared morphological consequences of global warming in North American migratory birds

“…Birds that migrate earlier and arrive first on the breeding grounds have been found to have longer wings than birds that arrive later (Bowlin ; Hahn et al ), raising the possibility that advancing spring phenology may select for longer wings (Møller et al ). Additional data are necessary to test this hypothesis.…”

“…In addition to decreases in body size, we also found a notable change in body shape: as multiple metrics of body size have declined, wing length has increased among nearly all species in the study. Longer and more pointed wings are associated with more efficient flight in birds, particularly for long distance flights (Pennycuick ; Møller et al ), suggesting that some aspect of recent global change may be selecting for more efficient flight across this diverse set of migratory birds. Given the consistent trends of decreasing body size that we observed alongside consistent increases in wing length, we hypothesized that these dynamics may be coupled.…”

Ten years tracking the migrations of small landbirds: Lessons learned in the golden age of bio-logging

“…A recent comparative study suggests that bird species with wings highly adapted to long-distance flying (i.e. high aspect ratio) exhibit less advancement of spring arrival (Moller et al 2017), a pattern that could be further explored by using tracking technology to examine the correlations between start-to-finish migration timing and wing morphology across species.…”