Meeting Paris agreement objectives will temper seabird winter distribution shifts in the North Atlantic Ocean

Climate change is altering the marine environment at a global scale, with some of the most dramatic changes occurring in Arctic regions. These changes may affect the distribution and migration patterns of marine species throughout the annual cycle. Species distribution models have provided detailed understanding of the responses of terrestrial species to climate changes, often based on observational data; biologging offers the opportunity to extend those models to migratory marine species that occur in marine environments where direct observation is difficult. We used species distribution modelling and tracking data to model past changes in the non-breeding distribution of thick-billed murres Uria lomvia from a colony in Hudson Bay, Canada, between 1982 and 2019. The predicted distribution of murres shifted during fall and winter. The largest shifts have occurred for fall migration, with range shits of 211 km west and 50 km north per decade, compared with a 29 km shift west per decade in winter. Regions of range expansions had larger declines in sea ice cover, smaller increases in sea surface temperature, and larger increases in air temperature than regions where the range was stable or declining. Murres migrate in and out of Hudson Bay as ice forms each fall and melts each spring. Habitat in Hudson Bay has become available later into the fall and earlier in the spring, such that habitat in Hudson Bay was available for 21 d longer in 2019 than in 1982. Clearly, marine climate is altering the distribution and annual cycle of migratory marine species that occur in areas with seasonal ice cover.

Section: Discussionsupporting

confidence: 59%

Northwest range shifts and shorter wintering period of an Arctic seabird in response to four decades of changing ocean climate

Patterson

Gilchrist

Gaston³

et al. 2021

“…The fact that several species share the same migration routes also increases the need to consider protection of 'migratory corridors' as a broader ecosystem unit rather than species-specific routes and areas. Non-breeding distributions of northern hemisphere seabirds are predicted to shift northwards in response to climate change (Hazen et al 2013, Clairbaux et al 2021. Furthermore, projected changes in wind regimes might also influence future migratory patterns (Weimerskirch et al 2012).…”

Section: Conservation Implicationsmentioning

confidence: 99%

Six pelagic seabird species of the North Atlantic engage in a fly-and-forage strategy during their migratory movements

Amélineau

Merkel

Tarroux

et al. 2021

Bird migration is commonly defined as a seasonal movement between breeding and non-breeding grounds. It generally involves relatively straight and directed large-scale movements, with a latitudinal change, and specific daily activity patterns comprising less or no foraging and more traveling time. Our main objective was to describe how this general definition applies to seabirds. We investigated migration characteristics of 6 pelagic seabird species (little auk Alle alle, Atlantic puffin Fratercula arctica, common guillemot Uria aalge, Brünnich’s guillemot U. lomvia, black-legged kittiwake Rissa tridactyla and northern fulmars Fulmarus glacialis). We analysed an extensive geolocator positional and saltwater immersion dataset from 29 colonies in the North-East Atlantic and across several years (2008-2019). We used a novel method to identify active migration periods based on segmentation of time series of track characteristics (latitude, longitude, net-squared displacement). Additionally, we used the saltwater immersion data of geolocators to infer bird activity. We found that the 6 species had, on average, 3 to 4 migration periods and 2 to 3 distinct stationary areas during the non-breeding season. On average, seabirds spent the winter at lower latitudes than their breeding colonies and followed specific migration routes rather than non-directionally dispersing from their colonies. Differences in daily activity patterns were small between migratory and stationary periods, suggesting that all species continued to forage and rest while migrating, engaging in a ‘fly-and-forage’ migratory strategy. We thereby demonstrate the importance of habitats visited during seabird migrations as those that are not just flown over, but which may be important for re-fuelling.

“…Despite being a commonly used proxy, winter NAO did not explain substantial variation in survival in any of the puffin populations. Previously documented (often lagged) effects of large-scale indices on seabird survival, chiefly NAO, have been explained by strong correlations with ocean surface temperature that, in turn, influences survival via prey distributions (Reid et al 1998, Leterme et al 2005, Sandvik et al 2008, Clairbaux et al 2021a. The NAO, which influences e.g.…”

Section: Winter Climate and Extreme Etcsmentioning

confidence: 99%

“…A lack of multi-year data on seabirds' non-breeding distributions and demography, as well as the inherent rarity of extreme events, makes quantifying the population-level effects of such events extremely challenging (Harris & Wanless 1996). Nevertheless, developments in largescale tracking data and establishment of long-term GLS-monitoring programmes can shed light on the location and behaviour of seabirds during this previously unobservable period (Frederiksen et al 2012, Fort et al 2013, Fauchald et al 2019, Clairbaux et al 2021a, making it possible to study climate effects in the non-breeding season in more detail (Reiertsen et al 2014, Descamps et al 2021). Our study is, to our knowledge, one of the few multi-colony studies to quantify the demographic effects of climate variables specific to seabird non-breeding areas.…”

Section: Winter Climate and Extreme Etcsmentioning

confidence: 99%

Inter-population synchrony in adult survival and effects of climate and extreme weather in non-breeding areas of Atlantic puffins

Reiertsen

Layton‐Matthews

Erikstad

et al. 2021

Seabirds are undergoing drastic declines globally and spend the non-breeding season at sea, making it challenging to study the drivers of their survival. Harsh weather and changes in climate conditions can have large impacts on seabird population dynamics through increased mortality. The intensity and persistence of extreme events are forecasted to increase with global warming. As shared conditions can induce population synchrony, multi-population studies of key demographic parameters are imperative to explore the influence of climate change. We used long-term mark-recapture data and position data to determine non-breeding stop-over areas of 5 Atlantic puffin (Fratercula arctica) populations over a latitudinal gradient in the Northeast Atlantic (56°11’-70°23’N). We investigated synchrony in adult survival in relation to shared stop-over areas. We quantified effects of extreme extra-tropical cyclones (ETCs) specific to populations’ stop-over areas and the North Atlantic Oscillation on adult survival. Populations with overlapping stop-over areas exhibited temporal synchrony in survival rates. Winter ETCs negatively influenced survival in 1 population, which was the one most exposed to extreme weather, but did not directly influence adult survival in the other 4 populations. Synchrony among populations with shared stop-over areas highlights the importance of these areas for adult survival, a key life-history rate. However, extreme weather was not identified as a driving factor for the majority of study populations. This suggests other factors in these areas, likely related to bottom-up trophic interactions, as environmental drivers of synchrony in the survival of Atlantic puffins.