Editing Mediterranean Sea (section)

==Biodiversity==
[[File:Eunicella.jpg|thumb|Soft coral ''[[Eunicella cavolini]]'']]
Unlike the vast multidirectional [[ocean current]]s in open [[ocean]]s within their respective [[oceanic zone]]s; [[Marine ecosystem|biodiversity]] in the Mediterranean Sea is stable due to the subtle but strong locked nature of [[Ocean current|currents]] which is favourable to life, even the smallest macroscopic type of [[Hydrothermal vent|volcanic life form]]. The stable [[marine ecosystem]] of the Mediterranean Sea and [[Sea surface temperature|sea temperature]] provides a nourishing environment for [[Marine biology|life in the deep sea]] to flourish while assuring a balanced [[aquatic ecosystem]] excluded from any external [[Deep sea|deep]] [[Ocean|oceanic factors]]. It is estimated that there are more than 17,000 [[Marine life|marine species]] in the Mediterranean Sea with generally higher marine [[biodiversity]] in [[Coast|coastal areas]], [[Continental shelf|continental shelves]], and decreases with depth.<ref>Coll, Marta, et al., "The biodiversity of the Mediterranean Sea: estimates, patterns, and threats". ''PLOS ONE 5.8'', 2010.</ref>

As a result of the drying of the sea during the [[Messinian salinity crisis]],<ref>[[Kenneth J. Hsu|Hsu K.J.]], "When the Mediterranean Dried Up" ''Scientific American'', Vol. '''227''', December 1972, p. 32</ref> the marine biota of the Mediterranean is derived primarily from the Atlantic Ocean. The North Atlantic is considerably colder and more nutrient-rich than the Mediterranean, and the marine life of the Mediterranean has had to adapt to its differing conditions in the five million years since the basin was reflooded.

The [[Alboran Sea]] is a transition zone between the two seas, containing a mix of Mediterranean and Atlantic species. The Alboran Sea has the largest population of [[bottlenose dolphin]]s in the Western Mediterranean, is home to the last population of [[harbour porpoise]]s in the Mediterranean and is the most important feeding grounds for [[loggerhead sea turtle]]s in Europe. The Alboran Sea also hosts important commercial fisheries, including [[sardine]]s and [[swordfish]]. The [[Mediterranean monk seal]]s live in the Aegean Sea in Greece. In 2003, the [[World Wildlife Fund]] raised concerns about the widespread [[drift net]] fishing endangering populations of dolphins, turtles, and other marine animals such as the [[Galathea strigosa|spiny squat lobster]].

There was a resident population of [[orca]]s in the Mediterranean until the 1980s, when they went extinct, probably due to long-term PCB exposure. There are still annual sightings of orca vagrants.<ref>Carrington, Damian. [https://www.theguardian.com/environment/2016/jan/14/uks-last-resident-killer-whales-doomed-to-extinction "UK's last resident killer whales 'doomed to extinction'"] {{Webarchive|url=https://web.archive.org/web/20190220003210/https://www.theguardian.com/environment/2016/jan/14/uks-last-resident-killer-whales-doomed-to-extinction |date=20 February 2019}}, ''[[The Guardian]]'', London, 14 January 2016. Retrieved 17 February 2019.</ref>

{{See also|Specially Protected Areas of Mediterranean Importance|List of fish of the Mediterranean Sea|List of fish of the Black Sea}}