Editing Steller's eider (section)

== Threats ==
The decline of Alaska-breeding Steller’s eider population is predominantly unclear. It has been attributed to changes to the Arctic climate, increased predation rates, hunting and consumption of lead shot, and disease.<ref name=":9">{{Cite web|last=Matz|first=Angela|date=February 1, 2008|title=Steller's Eider Reintroduction|url=https://training.fws.gov/courses/ALC/ALC3159/reports/final-reports/2008FR/stellers_eider_reintroduction.pdf|access-date=November 10, 2021|website=National Conservation Training Center}}</ref> Since their listing, additional threats such as exposure to oil and other contaminants have been identified.<ref name=":9" />

=== Climate change ===
Climate change may pose the greatest threat to Steller’s eiders. Primarily, climate change has caused Arctic tundra ponds to disappear, limiting the extent of suitable habitat for the species.<ref>{{Cite journal|last1=Andresen|first1=Christian G.|last2=Lougheed|first2=Vanessa L.|date=March 2015|title=Disappearing Arctic tundra ponds: Fine-scale analysis of surface hydrology in drained thaw lake basins over a 65 year period (1948-2013)|url=http://dx.doi.org/10.1002/2014jg002778|journal=Journal of Geophysical Research: Biogeosciences|volume=120|issue=3|pages=466–479|doi=10.1002/2014jg002778|bibcode=2015JGRG..120..466A|s2cid=135283843|issn=2169-8953|url-access=subscription}}</ref> Climate change has also been implicated in the collapse of rodent populations, forcing predators to exploit alternative prey such as the eggs and young of Steller's eider.<ref name=":6"/>

=== Lead poisoning ===
High levels of lead have been reported in Steller’s eiders that nest on the Alaska Arctic Coastal plain and in Spectacled Eiders that occupy the Yukon-Kuskokwim Delta, where Steller’s Eiders continue to nest in highly reduced densities.<ref>{{Cite journal|last1=Flint|first1=Paul L.|last2=Grand|first2=James B.|last3=Petersen|first3=Margaret R.|last4=Rockwell|first4=Robert F.|date=2016-06-01|title=Effects of Lead Exposure, Environmental Conditions, and Metapopulation Processes on Population Dynamics of Spectacled Eiders|journal=North American Fauna|volume=81|issue=1|pages=1–41|doi=10.3996/nafa.81.0001|issn=1944-4575|doi-access=free|bibcode=2016NAFA...81....1F }}</ref> Further studies have also shown that lead concentration was higher in individuals located close to industrialized regions than non-industrialized regions.<ref>{{Cite journal|last1=Miles|first1=A. Keith|last2=Flint|first2=Paul L.|last3=Trust|first3=Kimberley A.|last4=Ricca|first4=Mark A.|last5=Spring|first5=Sarah E.|last6=Arrieta|first6=Daniel E.|last7=Hollmen|first7=Tuula|last8=Wilson|first8=Barry W.|date=2007|title=Polycyclic Aromatic Hydrocarbon Exposure in Steller's Eiders (''Polysticta stelleri'') and Harlequin Ducks (''Histronicus histronicus'') in the Eastern Aleutian Islands, Alaska, USA|url=http://dx.doi.org/10.1897/07-259.1|journal=Environmental Toxicology and Chemistry|volume=26|issue=12|pages=2694–3303|doi=10.1897/07-259.1|pmid=18020694|bibcode=2007EnvTC..26.2694M |s2cid=28782733|issn=0730-7268|url-access=subscription}}</ref>

=== Nest predation ===
Nest predation by the [[Arctic fox]], [[pomarine jaeger]], [[snowy owl]], and [[common raven]] pose the greatest threat to Steller’s eider's nesting success rate.<ref name=":1" /> Studies have shown that Steller’s eider reproduce most successfully when lemmings are abundant, most likely resulting from predators transitioning between prey during years of lemming decline.<ref name=":10" />

=== Natural resource exploitation ===
The exploitation of natural resources such as oil and gas contributes to Steller’s eider habitat loss.<ref name=":10">{{Cite book|author=Safine, David Elliot|url=https://worldcat.org/oclc/946527072|title=Breeding ecology of Steller's and spectacled eiders nesting near Barrow, Alaska, 2012|date=2013|publisher=Endangered Species Branch, Fairbanks Fish and Wildlife Field Office, Fish and Wildlife Service, U.S. Department of the Interior|oclc=946527072}}</ref> Regional exploitation projects have increased the risk of [[Oil spill|spill contamination]]. At the same time, an increase in human presence and infrastructure have contributed to the demise of suitable habitats.<ref name=":10" />

=== Disease ===
Steller’s eiders transport the [[Avian influenza|Avian Influenza]] virus between Eurasia and North America during their migrations.<ref name=":11">{{Cite journal|last1=Ip|first1=Hon S|last2=Flint|first2=Paul L|last3=Franson|first3=J Christian|last4=Dusek|first4=Robert J|last5=Derksen|first5=Dirk V|last6=Gill|first6=Robert E|last7=Ely|first7=Craig R|last8=Pearce|first8=John M|last9=Lanctot|first9=Richard B|last10=Matsuoka|first10=Steven M|last11=Irons|first11=David B|date=2008-06-04|title=Prevalence of Influenza A viruses in wild migratory birds in Alaska: Patterns of variation in detection at a crossroads of intercontinental flyways|journal=Virology Journal|volume=5|issue=1|page=71|doi=10.1186/1743-422x-5-71|pmid=18533040|pmc=2435106|issn=1743-422X |doi-access=free }}</ref> Many recent studies have reported prominent infection rates amongst Steller’s eiders in Alaska, ranging from 0.2% to 5%.<ref name=":11" /><ref name=":12">{{Cite journal|last1=Wilson|first1=Heather M.|last2=Hall|first2=Jeffery S.|last3=Flint|first3=Paul L.|last4=Franson|first4=J. Christian|last5=Ely|first5=Craig R.|last6=Schmutz|first6=Joel A.|last7=Samuel|first7=Michael D.|date=2013-03-05|editor-last=Schnell|editor-first=Matthias Johannes|title=High Seroprevalence of Antibodies to Avian Influenza Viruses among Wild Waterfowl in Alaska: Implications for Surveillance|journal=PLOS ONE|language=en|volume=8|issue=3|pages=e58308|doi=10.1371/journal.pone.0058308|issn=1932-6203|pmc=3589273|pmid=23472177|bibcode=2013PLoSO...858308W|doi-access=free}}</ref><ref>{{Cite journal|last1=Ramey|first1=Andrew M.|last2=Pearce|first2=John M.|last3=Reeves|first3=Andrew B.|last4=Franson|first4=J. Christian|last5=Petersen|first5=Margaret R.|last6=Ip|first6=Hon S.|date=2011-07-16|title=Evidence for limited exchange of avian influenza viruses between seaducks and dabbling ducks at Alaska Peninsula coastal lagoons|url=http://dx.doi.org/10.1007/s00705-011-1059-z|journal=Archives of Virology|volume=156|issue=10|pages=1813–1821|doi=10.1007/s00705-011-1059-z|pmid=21766196|bibcode=2011ArcV..156.1813R |s2cid=19486083|issn=0304-8608|url-access=subscription}}</ref> It has been suggested that 80% of Steller’s eiders in Alaska are carriers of avian influenza [[Antibody|antibodies]].<ref name=":12" />

[[Escherichia coli|''E. coli'']] has also been reported in Alaska-breeding Steller’s eiders and is thought to be linked to wastewater from local human communities and industrialization.<ref>{{Cite journal|last1=Hollmén|first1=Tuula E.|last2=DebRoy|first2=Chitrita|last3=Flint|first3=Paul L.|last4=Safine|first4=David E.|last5=Schamber|first5=Jason L.|last6=Riddle|first6=Ann E.|last7=Trust|first7=Kimberly A.|date=2011|title=Molecular typing of Escherichia coli strains associated with threatened sea ducks and near-shore marine habitats of south-west Alaska|url=https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1758-2229.2010.00220.x|journal=Environmental Microbiology Reports|language=en|volume=3|issue=2|pages=262–269|doi=10.1111/j.1758-2229.2010.00220.x|pmid=23761259|bibcode=2011EnvMR...3..262H |issn=1758-2229|url-access=subscription}}</ref>