Earlier Arctic springs cause phenological mismatch in long-distance migrants

Abstract

An uneven change in climate across the Northern Hemisphere might severely affect the phenology of migrating animals, and especially long-distance migrating birds relying on local climatic cues to regulate the timing of migration. We examine the forward displacement of spring in both staging areas and breeding grounds of one such population, the East Atlantic light-bellied brent goose Branta bernicla hrota, and evaluate to what extent their migration has made a proportional response. On the breeding grounds in Svalbard the onset of spring advanced 2 weeks during the 24-year period, whereas no significant trend was found in the temperate staging areas. The timing of migration was constant throughout the study period, mirroring the static climatic conditions in the spring staging areas. These findings indicate a global warming-induced phenological mismatch in light-bellied brent geese, as these might arrive on their breeding grounds well beyond optimal breeding conditions. Our data indicated that productivity was negatively influenced by phenological delay and positively influenced by prolonged snow cover. We argue that both these effects might be representative of a negative influence of the growing phenological mismatch, because years with later thaw might partly offset the effects of increasingly earlier Svalbard springs. During the study period reproduction fell below annual mortality, and the population declined in recent years. The wider implications of these findings may extend to many migrating species, and highlight the urgent need to clarify how global change may influence cues and the associated timing of important life history activities.

Density dependence and phenological mismatch: consequences for growth and survival of sub-arctic nesting Canada Geese

“…Some studies have shown that peak nitrogen concentration can precede hatch by 2-3 weeks for both Arctic (Lepage et al 1998) and Subarctic nesting geese (Cadieux et al 2005). Although Canada Geese on Akimiski Island appeared to track plant phenology, i. e., there was a positive correlation between date of hatch and NDVI 50 , they often did not initiate nests early enough to fully keep pace with advanced plant phenology in early springs (i.e., not a perfect or 1:1 correlation) suggesting a potential mismatch (Clausen and Clausen 2013). Similarly, plant phenology advanced more quickly than did nest initiation timing by Greater Snow Geese (Chen caerulescens atlantica) during early springs in the High Arctic (Dickey et al 2008).…”

Surface radiation climatology for Ny-Ålesund, Svalbard (78.9° N), basic observations for trend detection

“…Using temperature as a potential indicator for the snow cover free season, the first day after summer of each year from 1993 to 2013 with a daily mean temperature below the freezing point has shifted by +9.0±11.2 days per decade, postponing the cold season by more than 2 weeks over the 21-year observation period. The prolonged season above the freezing point and consequently shorter period of snow covered ground allows for changes in vegetation growth and related behavior of migratory birds (Buchwal et al 2013;Kuhlmann Clausen and Clausen 2013).…”

Delayed egg‐laying and shortened incubation duration of Arctic‐breeding shorebirds coincide with climate cooling

“…In some areas of the Arctic, birds from small‐bodied sandpipers to large‐bodied geese have advanced the timing of first egg‐laying (Clausen & Clausen, 2013; Liebezeit, Gurney, Budde, Zack, & Ward, 2014; McKinnon, Picotin, Bolduc, Juillet, & Bêty, 2012). However, several studies have also shown no significant changes in breeding phenology of birds in the Arctic (Høye, Post, Meltofte, Schmidt, & Forchhammer, 2007; Mortensen, Schmidt, Høye, Damgaard, & Forchhammer, 2016; Reneerkens et al., 2016).…”