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

Authors:
  • Centre for Marine and Renewable Energy

Abstract

We explored the implications of reaching the Paris Agreement Objective of limiting global warming to <2°C for the future winter distribution of the North Atlantic seabird community. We predicted and quantified current and future winter habitats of five North Atlantic Ocean seabird species (Alle alle, Fratercula arctica, Uria aalge, Uria lomvia and Rissa tridactyla) using tracking data for ~1500 individuals through resource selection functions based on mechanistic modeling of seabird energy requirements, and a dynamic bioclimate envelope model of seabird prey. Future winter distributions were predicted to shift with climate change, especially when global warming exceed 2°C under a “no mitigation” scenario, modifying seabird wintering hotspots in the North Atlantic Ocean. Our findings suggest that meeting Paris agreement objectives, will limit changes in seabird selected habitat location and size in the North Atlantic Ocean during the 21st century. We thereby provide key information for the design of adaptive marine protected areas in a changing ocean.
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... To test the hypothesis that cyclones dramatically increase seabird energy requirements, we modeled species-specific, monthly energy requirements for each winter between 2000 and 2016 on a 1,000 km 3 1,000 km area off North Newfoundland (see Figure S1), using the mechanistic model Niche Mapper (see STAR Methods) 7 under four intensities of cyclones and under non-cyclonic conditions (see STAR Methods). Following the protocol used by Gr emillet and colleagues, 21 we calculated how Tim Guilford, 18 Nicholas P. Huffeldt, 20,22 Mark Jessopp, 23,24 Kasper L. Johansen, 20 Amy-Lee Kouwenberg, 25 Jannie F. Linnebjerg, 20 Heather L. Major, 26 Laura McFarlane Tranquilla, 25 Mark Mallory, 27 Flemming R. Merkel, 20 William Montevecchi, 28 Anders Mosbech, 20 Aevar Petersen, 29 and David Gr emillet 8,30, * many days each of the five studied species could fast before dying, when exposed to class 2, class 3, and class 4 cyclones in the studied area (see STAR Methods). Statistical analyses revealed several significant differences (Kruskal-Wallis, p < 0.05) in seabird energy requirements (see Table 1) between the six categories of conditions tested (class 1-4 cyclones, non-cyclonic conditions with usual seabird flight and diving activities, and non-cyclonic conditions with cyclonic seabird flight and diving activities). ...
... To test the hypothesis that cyclones dramatically increase seabird energy requirements, we modeled species-specific, monthly energy requirements for each winter between 2000 and 2016 on a 1,000 km 3 1,000 km area off North Newfoundland (see Figure S1), using the mechanistic model Niche Mapper (see STAR Methods) 7 under four intensities of cyclones and under non-cyclonic conditions (see STAR Methods). Following the protocol used by Gr emillet and colleagues, 21 we calculated how Tim Guilford, 18 Nicholas P. Huffeldt, 20,22 Mark Jessopp, 23,24 Kasper L. Johansen, 20 Amy-Lee Kouwenberg, 25 Jannie F. Linnebjerg, 20 Heather L. Major, 26 Laura McFarlane Tranquilla, 25 Mark Mallory, 27 Flemming R. Merkel, 20 William Montevecchi, 28 Anders Mosbech, 20 Aevar Petersen, 29 and David Gr emillet 8,30, * many days each of the five studied species could fast before dying, when exposed to class 2, class 3, and class 4 cyclones in the studied area (see STAR Methods). Statistical analyses revealed several significant differences (Kruskal-Wallis, p < 0.05) in seabird energy requirements (see Table 1) between the six categories of conditions tested (class 1-4 cyclones, non-cyclonic conditions with usual seabird flight and diving activities, and non-cyclonic conditions with cyclonic seabird flight and diving activities). ...
... To test the hypothesis that cyclones dramatically increase seabird energy requirements, we modeled species-specific, monthly energy requirements for each winter between 2000 and 2016 on a 1,000 km 3 1,000 km area off North Newfoundland (see Figure S1), using the mechanistic model Niche Mapper (see STAR Methods) 7 under four intensities of cyclones and under non-cyclonic conditions (see STAR Methods). Following the protocol used by Gr emillet and colleagues, 21 we calculated how Tim Guilford, 18 Nicholas P. Huffeldt, 20,22 Mark Jessopp, 23,24 Kasper L. Johansen, 20 Amy-Lee Kouwenberg, 25 Jannie F. Linnebjerg, 20 Heather L. Major, 26 Laura McFarlane Tranquilla, 25 Mark Mallory, 27 Flemming R. Merkel, 20 William Montevecchi, 28 Anders Mosbech, 20 Aevar Petersen, 29 and David Gr emillet 8,30, * many days each of the five studied species could fast before dying, when exposed to class 2, class 3, and class 4 cyclones in the studied area (see STAR Methods). Statistical analyses revealed several significant differences (Kruskal-Wallis, p < 0.05) in seabird energy requirements (see Table 1) between the six categories of conditions tested (class 1-4 cyclones, non-cyclonic conditions with usual seabird flight and diving activities, and non-cyclonic conditions with cyclonic seabird flight and diving activities). ...
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Each winter, the North Atlantic Ocean is the stage for numerous cyclones, the most severe ones leading to seabird mass-mortality events called ‘‘winter wrecks.’’ During these, thousands of emaciated seabird carcasses are washed ashore along European and North American coasts. Winter cyclones can therefore shape seabird population dynamics by affecting survival rates as well as the body condition of surviving individuals and thus their future reproduction. However, most often the geographic origins of impacted seabirds and the causes of their deaths remain unclear. We performed the first ocean-basin scale assessment of cyclone exposure in a seabird community by coupling winter tracking data for 1,500 individuals of five key North Atlantic seabird species (Alle alle, Fratercula arctica, Uria aalge, Uria lomvia, and Rissa tridactyla) and cyclone locations. We then explored the energetic consequences of different cyclonic conditions using a mechanistic bioenergetics model and tested the hypothesis that cyclones dramatically increase seabird energy requirements. We demonstrated that cyclones of high intensity impacted birds from all studied species and breeding colonies during winter but especially those aggregating in the Labrador Sea, the Davis Strait, the surroundings of Iceland, and the Barents Sea. Our broad-scale analyses suggested that cyclonic conditions do not increase seabird energy requirements, implying that they die because of the unavailability of their prey and/or their inability to feed during cyclones. Our study provides essential information on seabird cyclone exposure in a context of marked cyclone regime changes due to global warming.
... So far, dovekies have shown a remarkable resilience to the shift, but their ability to buffer its effects may be reaching its limit (Amélineau et al., 2019;Grémillet et al., 2012;Harding et al., 2009b). Understanding dovekie energetics is key to forecasting their current and future responses to global change (Clairbaux et al., 2021). ...
Preprint
Animal-borne telemetry devices provide essential insights into the life-history strategies of far-ranging species and allow us to understand how they interact with their environment. Many species in the seabird family Alcidae undergo a synchronous moult of all primary flight feathers during the non-breeding season, making them flightless and more susceptible to environmental stressors, including severe storms and prey shortages. However, the timing and location of moult remains largely unknown, with most information coming from studies on birds killed by storms or shot at sea. Using light-level geolocators with saltwater immersion loggers, we develop a method for determining flightless periods in the context of the annual cycle. Four Atlantic puffins (Fratercula arctica) were equipped with geolocator/immersion loggers on each leg to attempt to overcome issues of leg-tucking in plumage while sitting on the water, which confounds the interpretation of logger data. Light level and saltwater immersion time-series data were combined to correct for this issue. This approach was adapted and applied to 40 puffins equipped with the standard practice deployments of geolocators on one leg only. Flightless periods consistent with moult were identified in the dual-equipped birds, whereas moult identification in single-equipped birds was less definitive and should be treated with caution. Within the dual-equipped sample, we present evidence for two flightless moult periods per non-breeding season in two puffins that undertook more extensive migrations (> 2000km), and were flightless for up to 76 days in a single non-breeding season. A biannual flight feather moult is highly unusual among non-passerine birds, and may be unique to birds that undergo catastrophic moult, i.e. become flightless when moulting. Though our conclusions are based on a small sample, we have established a freely available methodological framework for future investigation of the moult patterns of this and other seabird species.
... So far, dovekies have shown a remarkable resilience to the shift, but their ability to buffer its effects may be reaching its limit (Amélineau et al., 2019;Grémillet et al., 2012;Harding et al., 2009b). Understanding dovekie energetics is key to forecasting their current and future responses to global change (Clairbaux et al., 2021). ...
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... Animal occurrence data can also be linked to population data to infer actual animal densities across marine areas (Carneiro et al., 2020;Beal et al., 2021). These approaches are particularly important in the context of exploited marine species , of marine spatial planning (Sequeira et al., 2019b), and of testing the incidence of different climate change scenarios (Clairbaux et al., 2021a). For this purpose, general additive mixed models (GAMMs) are the most commonly used statistical tool (but see Thuiller et al., 2009;Oppel et al., 2012 for review and alternatives), whereby their accuracy and reliability critically depend upon the quality of environmental information linked to animal tracking data (Yates et al., 2018), and of working at adequate spatio-temporal scales ). ...
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... None available NA information in some cases to call for a reduction in greenhouse gas emissions and the creation of new marine protected areas (e.g. Clairbaux et al., 2021). Yet, when it comes to identifying or prioritis- ...
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... For birds wintering in Europe, this mostly translates to shifts in a north-easterly direction up to 13 km/year (as reported for Bewick's swans, 126). Changing energetic requirements and prey availability under different scenarios of future climate are also expected to affect the winter distributions of the five most numerous species of seabirds in the North Atlantic, many of which breed in the Arctic [172], but shifts in winter distributions have not yet been shown for these species. ...
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Climate warming in the Arctic has led to warmer and earlier springs, and as a result, many food resources for migratory animals become available earlier in the season, as well as become distributed further northwards. To optimally profit from these resources, migratory animals are expected to arrive earlier in the Arctic, as well as shift their own spatial distributions northwards. Here, we review literature to assess whether Arctic migratory birds and mammals already show shifts in migration timing or distribution in response to the warming climate. Distribution shifts were most prominent in marine mammals, as expected from observed northward shifts of their resources. At least for many bird species, the ability to shift distributions is likely constrained by available habitat further north. Shifts in timing have been shown in many species of terrestrial birds and ungulates, as well as for polar bears. Within species, we found strong variation in shifts in timing and distributions between populations. Ou r review thus shows that many migratory animals display shifts in migration timing and spatial distribution in reaction to a warming Arctic. Importantly, we identify large knowledge gaps especially concerning distribution shifts and timing of autumn migration, especially for marine mammals. Our understanding of how migratory animals respond to climate change appears to be mostly limited by the lack of long-term monitoring studies.
... The greatest changes in distribution have occurred in the fall, where habitat available in Hudson Bay has increased substantially. Other recent studies have predicted that unchecked anth ropogenic climate change will result in a northward shift in the winter distribution of multiple seabird species in the North Atlantic (Clairbaux et al. 2021); our study shows that climate change has already contributed to shifts in the non-breeding distribution of murres from Coats Island. ...
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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.
... 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). ...
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We provide scripts in the R language and a Shiny app to facilitate future applications of our approach. We recommend that where sufficient tracking data are available, this framework be used to assess overlap of seabirds with at‐sea threats such as overharvesting, fisheries bycatch, shipping, offshore industry and pollutants. Based on such an analysis, conservation interventions could be directed towards areas where they have the greatest impact on populations. La identificación de áreas geográficas donde las densidades de animales son más altas de acuerdo a sus ciclos anuales es un paso crucial en la planificación de la conservación. Sin embargo, en ambientes marinos, puede ser particularmente difícil mapear la distribución de especies, y los métodos utilizados generalmente están sesgados hacia los adultos, sin tener en cuenta la distribución de individuos en otras etapas de su ciclo de vida que pueden representar una proporción sustancial de la población total. 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