Appendix 1: Sources and references for vulnerability assessment
1.1 Evidence for exposure (references)
1.1.1 Current impacts attributed to climate change:
Long-tailed Duck 1 - Wintering populations in Europe have declined due to climate change-driven changes in predation in breeding areas outside of Europe.- Hario, M., J. Rintala, and G. Nordenswan. “Dynamics of wintering long-tailed ducks in the Baltic Sea–the connection with lemming cycles, oil disasters, and hunting.” Suomen Riista 55 (2009): 83-96. Wintering populations in the Baltic have rapidly declined, in part because of the effects of climate change on key breeding sites outside of Europe. Due to changes in lemming availability, predators such as Arctic foxes have swapped to predating on duck eggs and young as alternative prey which, in turn, has resulted in decreased breeding success of long-tailed duck Clangula hyemalis on the Taimyr Peninsula.
- Hearn, R. D., A. L. Harrison, and P. A. Cranswick. “International single species action plan for the conservation of the long-tailed duck Clangula hyemalis, 2016–2025.” AEWA Tech Ser 57 (2015). Expands and updates the work above, the authors believe changes in predation have affected populations across western Siberia and northern Europe
- Hearn, R. D., A. L. Harrison, and P. A. Cranswick. “International single species action plan for the conservation of the long-tailed duck Clangula hyemalis, 2016–2025.” AEWA Tech Ser 57 (2015). Range expansion of predators such as Red Fox (Vulpes vulpes) may be influencing predator-prey relationships in the Arctic breeding grounds, and appears to be threatening the viability of the small Finnish Lapland breeding population of Long-tailed Ducks.
- Skabeikis, A., et al. “Effect of round goby (Neogobius melanostomus) invasion on blue mussel (Mytilus edulis trossulus) population and winter diet of the long-tailed duck (Clangula hyemalis).” Biological Invasions 21.3 (2019): 911-923. The benthic round goby has recently colonised the Baltic, which may have been facilitated by climate change (though this is speculation), as gobies strongly prefer warmer water. Competition with gobies has caused long-tailed ducks to switch prey, and there has been no observed change in mortality or condition. However, further climate change could promote goby expansion and further competition.
- Behrens, Jane W., et al. “Seasonal depth distribution and thermal experience of the non-indigenous round goby Neogobius melanostomus in the Baltic Sea: implications to key trophic relations.” Biological Invasions 24.2 (2022): 527-541. Makes a clearer link between gobies and warm water. Gobies strongly prefer warm water, which explain why they have now colonised the Baltic as climate change has resulted in warmer winters. It also suggests further climate change will assist further spread.
- Gardarsson, Arnthor. “Harlequin Ducks in Iceland.” Waterbirds 31.sp2 (2008): 8-14.; Gardarsson, Arnthor, and Árni Einarsson. “Relationships among food, reproductive success and density of Harlequin Ducks on the River Laxá at Myvatn, Iceland (1975-2002).” Waterbirds 31.sp2 (2008): 84-91. Using a multidecade dataset the authors conclude that southern populations in Iceland have decreased 1961-2001 while northern populations have increased. This is likely due to changes in blackfly abundance, which in turn is at least partly due to warmer springs and summers.
- Lehikoinen, Aleksi, and Kim Jaatinen. “Delayed autumn migration in northern European waterfowl.” Journal of Ornithology 153.2 (2012): 563-570. Scotor phenology is changing in response to climate change. Autumn migration is occurring later, birds are arriving later. Study carried out using long term data from Hango Observatory, southern Finland
- Tolon, Vincent, Pascal Provost, Christophe Aulert and Faustine Simon. “Etat des populations de macreuses en Europe, en France et en Basse-Normandie et analyse des principaux facteurs de distribution“. Report for Maison de l’Estuaire (2013). Wintering populations of scoters off the coast of France are declining and in some cases have disappearing. Cause is uncertain, but probably they have redistributed rather than died, and have shifted in response to reduced prey availability. There are several underlying causes, but climate change is likely to be a contributing factor.
- Tolon, Vincent, Pascal Provost, Christophe Aulert and Faustine Simon. “Etat des populations de macreuses en Europe, en France et en Basse-Normandie et analyse des principaux facteurs de distribution“. Report for Maison de l’Estuaire (2013). Wintering populations of scoters off the coast of France are declining and in some cases have disappeared. Cause is uncertain, but probably they have redistributed rather than died, and have shifted in response to reduced prey availability. There are several underlying causes, but climate change is likely to be a contributing factor.
- Virkkala, Raimo, et al. “Matching trends between recent distributional changes of northern-boreal birds and species-climate model predictions.” Biological Conservation 172 (2014): 124-127. Red-necked phalaropes have shifted north in Finland, the central density of the population has shifted significantly northwards. This shift is in correlation with climate change, but the underlying mechanism is not certain.
- Aarvak, Tomas, et al. “The European wintering population of Steller’s Eider Polysticta stelleri reassessed.” Bird Conservation International 23.3 (2013): 337-343. The number of Steller’s eiders wintering in the Baltic has dropped sharply. This is likely due to both a decrease in population size and a redistribution of wintering area to the White sea, most likely due to decreases in sea ice and a greater area of open water.
- Žydelis, Ramunas, et al. “Recent changes in the status of Steller’s Eider Polysticta stelleri wintering in Europe: a decline or redistribution?.” Bird Conservation International 16.3 (2006): 217-236. This paper precedes the one above and concludes that although there was a redistribution towards the Kola peninsula, the population may be declining as a whole.
- Fox, Anthony D., et al. “Current and potential threats to Nordic duck populations—a horizon scanning exercise.” Annales Zoologici Fennici. Vol. 52. No. 4. Finnish Zoological and Botanical Publishing Board, 2015. Historically chick survival in the Baltic has been affected by summer precipitation and wind, both of these climatic variables have increased over recent decades and are projected to increase further in the future.
- Lehikoinen, Aleksi, M. Kilpi, and Markus Öst. “Winter climate affects subsequent breeding success of common eiders.” Global Change Biology 12.7 (2006): 1355-1365. There is a lagged effect of winter NAO on eider breeding condition (negative NAO means colder conditions, more storms, more sea ice and lower breeding condition). The authors suggest that climate change will benefit eider populations in the Baltic as winters become milder.
- D’Alba, Liliana, Pat Monaghan, and Ruedi G. Nager. “Advances in laying date and increasing population size suggest positive responses to climate change in common eiders Somateria mollissima in Iceland.” Ibis 152.1 (2010): 19-28. Using a 30 year dataset in Iceland, the authors believe climate change is a major driver behind the population increase. Milder summers mean more nests, because fewer females skip breeding (as they are in higher condition)
- Mehlum, Fridtjof. “Effects of sea ice on breeding numbers and clutch size of a high arctic population of the common eider Somateria mollissima.” Polar Science 6.1 (2012): 143-153. Eiders in Svalbard seem to benefit from early sea ice break up (assessed using a 15 year dataset) as it increases foraging time and adult condition and therefore the proportion of the population that commits to breeding. The authors conclude that further warming is likely to benefit populations.
- D’Alba, Liliana, Pat Monaghan, and Ruedi G. Nager. “Advances in laying date and increasing population size suggest positive responses to climate change in common eiders Somateria mollissima in Iceland.” Ibis 152.1 (2010): 19-28. In Iceland, eiders laid earlier following warmer winters. The exact reason is uncertain but could be because adults are in better condition following winter, or because key prey species (especially mussels) are available earlier in milder winters.
- Prop, Jouke, et al. “Climate change and the increasing impact of polar bears on bird populations.” Frontiers in Ecology and Evolution 3 (2015): 33. Study conducted on Svalbard, polar bears appear to be swapping prey species from seals due to a lack of sea ice. Several bird species are increasingly predated, prominantly eiders.
1.1.2 Change in European range size between present day and 2100:
Using a species distribution model (SDM) we correlated species occurrence during the breeding season with a number of terrestrial and marine environmental variables. Species range data came from the European Breeding Bird Atlas (EBBA2) database. Present-day and 2100 terrestrial data were downloaded from the WorldClim database. We used data from the MRI-ESM2 general circulation model (GCM), which is a high-performing model over Europe. Present-day and 2100 marine data were downloaded from the Bio-Oracle database which averages predictions of marine variables from several different atmospheric-oceanic general circulation models (AOGCMS; for full details see Assis et al., 2017). For the map presented in the summary we used representative concentration pathway (RCP) 4.5, which is an “intermediate” emissions scenario. All data were at 5-minute resolution.
- For Long-tailed Duck, Harlequin Duck, Velvet Scoter, Common Scoter, Red-breasted Merganser, Red Phalarope, and Red-necked Phalarope we included the following terrestrial variables: Mean temperature of the warmest month, precipitation during breeding season, distance to sea
- For Steller’s Eider, Common Eider, and King Eider we included the following terrestrial variables: Mean temperature of the warmest month, precipitation during breeding season, isolation of landmass, area of landmass, distance to sea
- For Steller’s Eider, Common Eider, and King Eider we included the following marine variables: Sea surface temperature (during the winter), salinity, maximum chlorophyll concentration, bathymetry (depth and variance)
Several other variables may strongly influence the distribution ofducks and phalaropesand it is not possible to include all possible variables in a given model. However the following variables have previously been found to be important to predicting the distribution of ducks and phalaropes in Europe: freshwater depth, freshwater ph, freshwater chlorophyll concentrationseabed substrate (sediment granulometry). For local assessments of climate change, we recommend these variables are strongly considered. We hope to incorporate these variables into future versions of this guidance document.
After running our model we generated a present-day map where every grid-cell is given a habitat suitability score between 0 and 1, where 1 is very suitable habitat and 0 is not at all suitable. We then compared this with a corresponding map built with 2100 data, and highlighted currently inhabitated areas where 1) suitability drops sharply (i.e. by more than 0.1) and 2) suitability drops below a probability threshold set by the model. Conversely we also highlighted areas where suitability rose sharply and above a given threshold. While a drop in habitat suitability is likely to result in population declines, it is not a certainty, and it does not mean that a population will be extinct in 2100 or that a population is doomed to extinction. With conservation action and careful management, along with changes in human behaviour, such declines may be mitigated or in some cases prevented. For a full explanation of the model see the accompanying ‘Methodology’ document.
Underlying data were downloaded from:- Keller, V., Herrando, S., Voríšek, P., Franch, M., Kipson, M., Milanesi, P., Martí, D., Anton, M., Klvanová, A., Kalyakin, M.V., Bauer, H.-G. & Foppen, R.P.B. (2020). European Breeding Bird Atlas 2: Distribution, Abundance and Change. European Bird Census Council & Lynx Edicions, Barcelona. Source of range data
- Fick, S. E., & Hijmans, R. J. (2017). Worldclim 2: New 1-km spatial resolution climate surfaces for global land areas. International Journal of Climatology. http://worldclim.org/version2. Source of present-day and 2100 terrestrial data.
- Assis, J., Tyberghein, L., Bosch, S., Verbruggen, H., Serrão, E. A., & De Clerck, O. (2018). Bio-ORACLE v2.0: Extending marine data layers for bioclimatic modelling. Global Ecology and Biogeography, 27(3), 277–284. https://doi.org/10.1111/geb.12693. Source of present-day and 2100 marine data
1.1.3 Changes in key prey species:
We first identified the key prey species for each species. This can be variable across a species range, but if available evidence suggested at least one major population is highly dependent on a particular prey species, then typically this species would be included. Lists of prey species were compiled from published sources, then verified and expanded following consultation with conservation practitioners. Afterwards we compiled current and projected maps of prey ranges to assess where key prey species may disappear in the near future. If any of the key species are predicted to vanish or drastically reduce in abundance in the current foraging range a given species, we marked this on the summary map. We used several sources to collate range information, but for preference we used data from COPERNICUS as they include projected abundance. For species where this was not available we used habitat suitability instead. In all cases we used RCP 4.5, which is an “intermediate” emissions scenario. For species in the COPERNICUS database we used the 0.6 maximum sustainable yield parameter, which assumes international co-operation to work towards fish-stock sustainability. Our assessment is therefore relatively conservative in terms of changes in prey species.
- Morkune, Rasa, et al. “Triple stable isotope analysis to estimate the diet of the Velvet Scoter (Melanitta fusca) in the Baltic Sea.” PeerJ 6 (2018): e5128.
- Durinck, Jan, et al. “Diet of the common scoter Melanitta nigra and velvet scoter Melanitta fusca wintering in the North Sea.” Ornis Fennica 70.4 (1993): 215-218.
- Stempniewicz, L. E. C. H. “The food intake of two Scoters Melanitta fusca and M. nigra wintering in the Gulf of Gdansk, Polish Baltic coast.” Vår Fågelv., Suppl 11 (1986): 211-214.
- Carboneras, C. and G. M. Kirwan (2020). Common Scoter (Melanitta nigra), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.blksco1.01
- Hartley, Clive. “Status and distribution of Common Scoters on the Solway Firth.” British Birds 100.5 (2007): 280.
- Durinck, Jan, et al. “Diet of the common scoter Melanitta nigra and velvet scoter Melanitta fusca wintering in the North Sea.” Ornis Fennica 70.4 (1993): 215-218.
- Stempniewicz, L. E. C. H. “The food intake of two Scoters Melanitta fusca and M. nigra wintering in the Gulf of Gdansk, Polish Baltic coast.” Vår Fågelv., Suppl 11 (1986): 211-214.
- Craik, S., J. Pearce, and R. D. Titman (2020). Red-breasted Merganser (Mergus serrator), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.rebmer.01
- Bengtson, Sven-Axel. Food and feeding of diving ducks breeding at Lake Myvatn, Iceland. 1971.
- Feltham, Mark. “The diet of red-breasted mergansers (Mergus serrator) during the smolt run in NE Scotland: the importance of salmon (Salmo salar) smolts and parr.” Journal of Zoology 222.2 (1990): 285-292.
- Birds of the World
- Bustnes, Jan O., et al. “The diet of Steller’s Eiders wintering in Varangerfjord, northern Norway.” The Wilson Journal of Ornithology 112.1 (2000): 8-13.
- Nygård, Torgeir, Bjørn Frantzen, and Saulius Švažas. “Steller’s Eiders Polysticta stelleri wintering in Europe: numbers, distribution and origin.” Wildfowl 46.46 (1995): 140-156.
- Goudie, R. I., G. J. Robertson, and A. Reed (2020). Common Eider (Somateria mollissima), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.comeid.01
- Bustnes, Jan Ove, and Kjell Einar Erikstad. “The diets of sympatric wintering populations of Common Eider Somateria mollissima and King Eider S. spectabilis in Northern Norway.” Ornis Fennica 65.4 (1988): 163-168.
- Kristjánsson, Thordur Örn, Jón Einar Jónsson, and Jörundur Svavarsson. “Spring diet of common eiders (Somateria mollissima) in Breiðafjörður, West Iceland, indicates non-bivalve preferences.” Polar Biology 36.1 (2013): 51-59.
- Powell, A. N. and R. S. Suydam (2020). King Eider (Somateria spectabilis), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.kineid.01
- Frimer, Ole. “Diet of moulting king eiders Somateria spectabilis at Disko Island, West Greenland.” Ornis Fennica 74 (1997): 187-194.
- COPERNICUS. (2021). Fish abundance and catch data for the Northwest European Shelf and Mediterranean Sea from 2006 to 2098 derived from climate projections. https://doi.org/10.24381/cds.39c97304
- Kesner-Reyes, K., Kaschner, K., Kullander, S., Garilao, C., Barile, J., & Froese., R. (2019). AquaMaps: Predicted range maps for aquatic species. In R. Froese & D. Pauly (Eds.), FishBase. https://www.aquamaps.org
1.1.4 Climate change impacts outside of Europe
Long-tailed Duck Species is known to be sensitive in North America to changes in sea temperature, fluctuations in NAO, and, in particular, the presence of sea ice. Such changes cause year-to-year changes in their wintering distribution across America. A decline in sea ice is likely to result in a range shift of wintering populations, and it is possible that such a redistribution has already occurred in the Baltic.- Zipkin, Elise F., et al. “Distribution patterns of wintering sea ducks in relation to the North Atlantic Oscillation and local environmental characteristics.” Oecologia 163.4 (2010): 893-902.
- Flint, Paul L. “Changes in size and trends of North American sea duck populations associated with North Pacific oceanic regime shifts.” Marine Biology 160.1 (2013): 59-65.
- Drever, Mark C., et al. “Population vulnerability to climate change linked to timing of breeding in boreal ducks.” Global Change Biology 18.2 (2012): 480-492.
- Drever, Mark C., et al. “Population vulnerability to climate change linked to timing of breeding in boreal ducks.” Global Change Biology 18.2 (2012): 480-492.
- Martin, Jean-Louis, et al. “Late snowmelt can result in smaller eggs in Arctic shorebirds.” Polar Biology 41.11 (2018): 2289-2295.
- Sydeman, William J., et al. “Climate–ecosystem change off southern California: time-dependent seabird predator–prey numerical responses.” Deep Sea Research Part II: Topical Studies in Oceanography 112 (2015): 158-170.
- Gall, Adrian E., et al. “Ecological shift from piscivorous to planktivorous seabirds in the Chukchi Sea, 1975–2012.” Polar Biology 40.1 (2017): 61-78.
- Liebezeit, Joseph R., et al. “Phenological advancement in arctic bird species: relative importance of snow melt and ecological factors.” Polar Biology 37.9 (2014): 1309-1320.
- Nussbaumer, Raphaël, et al. “Investigating the influence of the extreme Indian Ocean Dipole on the 2020 influx of Red-necked Phalaropes Phalaropus lobatus in Kenya.” Ostrich (2021): 1-9.
- Iles, David T., et al. “Predators, alternative prey and climate influence annual breeding success of a long-lived sea duck.” Journal of Animal Ecology 82.3 (2013): 683-693.
- Mallory, M. L., et al. “Effects of climate change, altered sea-ice distribution and seasonal phenology on marine birds.” A little less Arctic. Springer, Dordrecht, 2010. 179-195.
- Lovvorn, James R., et al. “Limits to benthic feeding by eiders in a vital Arctic migration corridor due to localized prey and changing sea ice.” Progress in Oceanography 136 (2015): 162-174.
1.2 Sensitivity (references)
We used a list of candidate traits based on that in Foden & Young (2016) that indicate high sensitivity and identified which, if any, ducks and phalaropes possessed. In brief, we consulted published literature as well as expert knowledge and online databases such as Birdlife (http://datazone.birdlife.org/) and Birds of the World (https://birdsoftheworld.org), to assess whether ducks and phalaropes have either 1) Specialised habitat and/or microhabitat requirement 2) Environmental tolerances or thresholds (at any life stage) that are likely to be exceeded due to climate change 3) Dependence on environmental triggers that are likely to be disrupted by climate change, 4) Dependence on interspecific interactions that are likely to be disrupted by climate change or 5) High rarity.
For more detail and a full list of traits see:- Foden, W. B., & Young, B. E. (2016). IUCN SSC guidelines for assessing species’ vulnerability to climate change. Version 1.0 (Occasional paper of the IUCN Species Survival Commission No. 59)
1.3 Adaptive capacity (references)
We used a list of candidate traits based on that in Foden & Young (2016) that indicate adaptive capacity and identified which, if any, ducks and phalaropes possessed. In brief, we consulted published literature as well as expert knowledge and online databases such as Birdlife (http://datazone.birdlife.org/) and Birds of the World (https://birdsoftheworld.org), to assess whether ducks and phalaropes have either: 1) High phenotypic plasticity. 2) High dispersal ability or 3) High evolvability.
For more detail and a full list of traits see:- Foden, W. B., & Young, B. E. (2016). IUCN SSC guidelines for assessing species’ vulnerability to climate change. Version 1.0 (Occasional paper of the IUCN Species Survival Commission No. 59)