Editing North Sea (section)

== Nature ==
=== Fish and shellfish ===
{{See also|List of fish of the North Sea}}
[[File:Bank met ondermeer kokkels mosselen en Japanse oesters in de Waddenzee bij Schiermonnikoog.jpg|thumb|[[Pacific oyster]]s, [[blue mussel]]s and [[cockle (bivalve)|cockle]]s in the [[Wadden Sea]] in the Netherlands]]

[[Copepod]]s and other [[zooplankton]] are plentiful in the North Sea. These tiny organisms are crucial elements of the [[food chain]] supporting many species of fish.<ref name="Ecoserve"/> Over 230 species of [[fish]] live in the North Sea. [[Cod]], [[haddock]], [[whiting (fish)|whiting]], [[saithe]], [[plaice]], [[sole (fish)|sole]], [[mackerel]], [[herring]], [[pouting (fish)|pouting]], [[sprat]], and [[sandeel]] are all very common and are fished commercially.<ref name="Ecoserve"/><ref name="OSPAR">{{cite web
|title = Quality Status Report for the Greater North Sea
|publisher = [[Convention for the Protection of the Marine Environment of the North-East Atlantic]] (OSPAR)
|year = 2010
|url = http://qsr2010.ospar.org/en/ch12_02.html
|access-date = 23 June 2013
|archive-date = 25 January 2012
|archive-url = https://web.archive.org/web/20120125104206/http://qsr2010.ospar.org/en/ch12_02.html
|url-status = live
}}</ref> Due to the various depths of the North Sea trenches and differences in salinity, temperature, and water movement, some fish such as blue-mouth redfish and [[rabbitfish]] reside only in small areas of the North Sea.<ref>{{cite journal |author1=Piet, G. J. |author2=van Hal, R. |author3=Greenstreet, S. P. R. |year=2009 |title=Modelling the direct impact of bottom trawling on the North Sea fish community to derive estimates of fishing mortality for non-target fish species |journal=ICES Journal of Marine Science |volume=66 |issue=9 |pages=1985–1998 |doi=10.1093/icesjms/fsp162 |doi-access=free }}</ref>

[[Crustacean]]s are also commonly found throughout the sea. [[Norway lobster]], [[Pandalus borealis|deep-water prawns]], and [[Crangon crangon|brown shrimp]] are all commercially fished, but other species of [[lobster]], [[Caridea|shrimp]], [[oyster]], [[mussel]]s and [[clam]]s all live in the North Sea.<ref name="Ecoserve"/> Recently non-indigenous species have become established including the [[Pacific oyster]] and [[Atlantic jackknife clam]].<ref name="OSPAR"/>

===Birds===
The coasts of the North Sea are home to [[nature reserve]]s including the [[Ythan Estuary]], [[Fowlsheugh]] Nature Preserve, and [[Farne Islands]] in the UK and the [[Wadden Sea National Parks]] in Denmark, Germany and the Netherlands.<ref name="Ecoserve">{{cite web
| title = MarBEF Educational Pullout: The North Sea
| work = Ecoserve
| publisher = [[MarBEF]] Educational Pullout Issue 4
| url = http://www.marbef.org/outreach/downloads/North%20sea%20pullout.pdf
| access-date = 12 January 2009
| archive-url = https://web.archive.org/web/20090205005633/http://www.marbef.org/outreach/downloads/North%20sea%20pullout.pdf
| archive-date = 5 February 2009
| url-status = dead
}}</ref> These locations provide breeding [[habitat (ecology)|habitat]] for dozens of bird species. Tens of millions of birds make use of the North Sea for breeding, feeding, or migratory stopovers every year. Populations of [[black-legged kittiwake]]s, [[Atlantic puffin]]s, [[northern gannet]]s, [[northern fulmar]]s, and species of [[petrel]]s, [[seaduck]]s, [[loon]]s (divers), [[cormorant]]s, [[gull]]s, [[auk]]s, and [[tern]]s, and many other seabirds make these coasts popular for [[birdwatching]].<ref name="Ecoserve"/><ref name="OSPAR"/>

[[File:European seagull on the coast of North Sea.jpg|thumb|alt=European seagull on the coast of North Sea|European seagull on the coast of North Sea]]

===Marine mammals===
[[File:Bottlenose dolphin with young.JPG|thumb|A female [[bottlenose dolphin]] with her young in [[Moray Firth]], Scotland]]
The North Sea is also home to marine mammals. [[Common seal]]s, [[grey seal]]s, and [[harbour porpoise]]s can be found along the coasts, at marine installations, and on islands. The very northern North Sea islands such as the Shetland Islands are occasionally home to a larger variety of [[pinnipeds]] including [[bearded seal|bearded]], [[harp seal|harp]], [[hooded seal|hooded]] and [[ringed seal]]s, and even [[walrus]].<ref>{{cite web |url=http://www.ecomare.nl/index.php?id=4184&L=2 |title=Walrus |work=Ecomare |access-date=23 June 2013 |archive-date=2 May 2014 |archive-url=https://web.archive.org/web/20140502205938/http://www.ecomare.nl/index.php?id=4184&L=2 |url-status=live }}</ref> North Sea [[cetaceans]] include various [[porpoise]], [[dolphin]] and [[whale]] species.<ref name="OSPAR"/><ref>{{Cite book |title = Whales and dolphins in the North Sea 'on the increase' |publisher = Newcastle University Press Release |date = 2 April 2005 |url = http://www.ncl.ac.uk/press.office/press.release/item/?ref=1112607082 |access-date = 21 December 2007 |url-status = dead |archive-url = https://web.archive.org/web/20090101213218/http://www.ncl.ac.uk/press.office/press.release/item/?ref=1112607082 |archive-date = 1 January 2009 }}</ref>

===Flora===
[[File:Phytoplankton Bloom in the North Sea.jpg|thumb|[[Phytoplankton]] bloom in the North Sea]]

Plant species in the North Sea include species of [[wrack (science)|wrack]], among them [[bladder wrack]], [[knotted wrack]], and serrated wrack. [[Algae]], macroalgal, and [[kelp]], such as oarweed and laminaria hyperboria, and species of [[maerl]] are found as well.<ref name="OSPAR"/> [[Zostera|Eelgrass]], formerly common in the entirety of the Wadden Sea, was nearly wiped out in the 20th century by a disease.<ref>{{cite journal
|last=Nienhuis
|first=P.H.
|s2cid=37221865
|title =Causes of the eelgrass wasting disease: Van der Werff's changing theories
|journal=Aquatic Ecology
|issue=1
|volume=28
|year = 2008
|doi=10.1007/BF02334245
|pages=55–61}}
</ref> Similarly, [[Seagrass|sea grass]] used to coat huge tracts of ocean floor, but have been damaged by trawling and dredging have diminished its habitat and prevented its return.<ref>{{cite book |url=http://www.nap.edu/openbook.php?record_id=10323&page=27 |title=Effects of Trawling and Dredging on Seafloor Habitat |publisher=[[United States National Academy of Sciences|National Academy of Sciences]] |others=Ocean Studies Board, Division on Earth and Life Studies, [[National Research Council (United States)|National Research Council]] |year=2008 |isbn=978-0-309-08340-9 |chapter=Effects of Trawling and Dredging |doi=10.17226/10323 |access-date=2 November 2008 |archive-url=https://web.archive.org/web/20110515185007/http://www.nap.edu/openbook.php?record_id=10323&page=27 |archive-date=15 May 2011 |url-status=live}}</ref> Invasive [[Sargassum muticum|Japanese seaweed]] has spread along the shores of the sea clogging harbours and inlets and has become a nuisance.<ref>{{cite book
|last=Tait
|first=Ronald Victor
|author2=Frances Dipper
|title=Elements of Marine Ecology
|url=https://books.google.com/books?id=gHrXsKJ89rEC&pg=PA432
|year=1998
|publisher=Butterworth-Heinemann
|isbn=9780750620888
|page=432
|access-date=1 July 2020
|archive-date=17 April 2023
|archive-url=https://web.archive.org/web/20230417083626/https://books.google.com/books?id=gHrXsKJ89rEC&pg=PA432
|url-status=live
}}</ref>

===Biodiversity and conservation===
Due to the heavy human populations and high level of industrialization along its shores, the wildlife of the North Sea has suffered from pollution, overhunting, and overfishing. [[Flamingo]]s and [[pelican]]s were once found along the southern shores of the North Sea, but became extinct over the second millennium.<ref>{{cite web
 |title        = Extinct / extirpated species
 |work         = Dr.&nbsp;Ransom A. Myers – Research group website
 |publisher    = Future of Marine Animal Populations / Census of Marine Life
 |date         = 27 October 2006
 |url          = http://www.fmap.ca/ramweb/media/biodiversity_loss/downloads/Examples_regional_extinctions.doc
 |url-status   = dead
 |access-date  = 24 November 2008
 |format       = doc
 |archive-url  = https://wayback.archive-it.org/all/20081217143715/http://www.fmap.ca/ramweb/media/biodiversity_loss/downloads/Examples_regional_extinctions.doc
 |archive-date = 17 December 2008
 }}</ref> Walruses frequented the Orkney Islands through the mid-16th&nbsp;century, as both Sable Island and Orkney Islands lay within their normal range.<ref>
{{cite journal
 |last = Ray  |first = C.E.
 |year = 1960
 |title = ''Trichecodon huxlei'' (Mammalia: Odobenidae) in the Pleaistocene of southeastern United States
 |journal= Bulletin of the Museum of Comparative Zoology
 |volume = 122   |pages = 129–142
}}
</ref> [[Gray whale|Grey whale]]s also resided in the North Sea but were driven to extinction in the Atlantic in the 17th&nbsp;century<ref>{{cite web
 |website      = The Extinction Website
 |series       = Species Info
 |title        = Atlantic Grey Whale
 |date         = 19 January 2008
 |url          = http://www.petermaas.nl/extinct/speciesinfo/atlanticgreywhale.htm
 |access-date  = 3 December 2008
 |url-status   = dead
 |archive-url  = https://web.archive.org/web/20090104224507/http://www.petermaas.nl/extinct/speciesinfo/atlanticgreywhale.htm
 |archive-date = 4 January 2009
 }}</ref> Other species have dramatically declined in population, though they are still found. [[North Atlantic right whale]]s, [[sturgeon]], [[shad]], [[Batoidea|rays]], [[Skate (fish)|skate]]s, [[salmon]], and other species were common in the North Sea until the 20th&nbsp;century, when numbers declined due to [[overfishing]].<ref>{{cite news
 |last = Brown
 |first = Paul
 |date = 21 March 2002
|title = North Sea in crisis as skate dies out: Ban placed on large areas to stave off risk of species being destroyed
 |newspaper = [[The Guardian]]
 |location = London, UK
 |publisher = Guardian Unlimited, Guardian News and Media Limited
 |url = https://www.theguardian.com/Archive/Article/0,4273,4378387,00.html
 |access-date = 3 December 2008
 |archive-date = 17 April 2023
 |archive-url = https://web.archive.org/web/20230417083626/https://www.theguardian.com/environment/2002/mar/21/fish.food
 |url-status = live
 }}</ref><ref>{{cite news
 |last1        = Williot
 |first1       = Patrick
 |last2        = Rochard
 |first2       = Éric
 |series       = Ecosystems and territories
 |title        = Sturgeon: Restoring an endangered species
 |publisher    = Cemagref
 |url          = http://www.cemagref.fr/english/seven/News/07/25ans/ETsturgeon.pdf
 |access-date  = 3 December 2008
 |archive-url  = https://web.archive.org/web/20081217143716/http://www.cemagref.fr/english/seven/News/07/25ans/ETsturgeon.pdf
 |archive-date = 17 December 2008
 |url-status   = dead
}}</ref>

Other factors like the introduction of [[non-indigenous species]], [[industrial pollution|industrial]] and [[agricultural pollution]], [[trawling]] and [[dredging]], human-induced [[eutrophication]], construction on coastal breeding and feeding grounds, sand and gravel extraction, [[offshore construction]], and heavy shipping traffic have also contributed to the decline.<ref name="OSPAR"/> For example, a resident [[orca]] pod was lost in the 1960s, presumably due to the peak in [[Polychlorinated biphenyl|PCB]] pollution in this time period.<ref>{{cite news
 |last=Carrington
 |first=Damian
 |date=14 January 2016
 |title=UK's last resident killer whales 'doomed to extinction'
 |newspaper=[[The Guardian]]
 |place=London, UK
 |url=https://www.theguardian.com/environment/2016/jan/14/uks-last-resident-killer-whales-doomed-to-extinction
 |access-date=17 February 2019
 |archive-date=20 February 2019
 |archive-url=https://web.archive.org/web/20190220003210/https://www.theguardian.com/environment/2016/jan/14/uks-last-resident-killer-whales-doomed-to-extinction
 |url-status=live
 }}</ref>

The OSPAR commission manages the [[OSPAR]] convention to counteract the harmful effects of human activity on wildlife in the North Sea, preserve [[endangered species]], and provide environmental protection.<ref>
{{cite web
 |title=OSPAR Convention
 |publisher=European Union
 |year=2000
 |url=http://europa.eu/scadplus/leg/en/lvb/l28061.htm
 |access-date=30 November 2008 |url-status=dead
 |archive-url=https://web.archive.org/web/20090108222855/http://europa.eu/scadplus/leg/en/lvb/l28061.htm
 |archive-date=8 January 2009
}}
</ref> All North Sea border states are signatories of the [[MARPOL 73/78]] Accords, which preserve the marine environment by preventing pollution from ships.<ref>{{cite journal
 | title = Directive 2000/59/EC of the European Parliament and of the Council of 27&nbsp;November 2000 on port reception facilities for ship-generated waste and cargo residues
 | date = 28 December 2000
 | journal = Official Journal of the European Communities
 | id = 28 December 2000 L 332/81
 | url = http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2000:332:0081:0089:EN:PDF
 | access-date = 12 January 2009
 | archive-date = 10 May 2011
 | archive-url = https://web.archive.org/web/20110510104253/http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2000:332:0081:0089:EN:PDF
 | url-status = live
 }} "Member States have ratified Marpol 73/78".</ref> Germany, Denmark, and the Netherlands also have a trilateral agreement for the protection of the [[Wadden Sea]], or [[mudflat]]s, which run along the coasts of the three countries on the southern edge of the North Sea.<ref>
{{cite report
 |chapter      = Wadden Sea region case study
 |date         = 1 June 2006
 |title        = Scottish Natural Heritage: A review of relevant experience in sustainable tourism in the coastal and marine environment, case studies, level 1, Wadden Sea region
 |publisher    = Stevens & Associates
 |chapter-url          = http://www.snh.org.uk/pdfs/strategy/CMNP/Case%20Study/Wadden%20Sea%20Region%20Final.pdf
 |access-date   = 1 December 2008 |url-status = dead
 |archive-url  = https://web.archive.org/web/20081217143713/http://www.snh.org.uk/pdfs/strategy/CMNP/Case%20Study/Wadden%20Sea%20Region%20Final.pdf
 |archive-date  = 17 December 2008
}}
</ref>