View source for Flounder

{{short description|Group of flatfish species}}
{{About|the fish|other uses}}
{{more citations needed|date = February 2012}}
[[File:Pseudopleuronectes americanus.jpg|thumb|250px|right|[[Winter flounder]], ''Pseudopleuronectes americanus'']]
[[File:Flounder hawaii.jpg|thumb|250px|right|[[Flowery flounder]], ''Bothus mancus'', <br />Bahía de la Chiva, at [[Hawaii]]]]
'''Flounders''' are a group of [[flatfish]] species. They are [[demersal fish]], found at the bottom of oceans around the world; some species will also enter [[estuary|estuaries]].

== Taxonomy ==
The name "flounder" is used for several only distantly related species, though all are in the suborder [[Pleuronectoidei]] (families [[Achiropsettidae]], [[Bothidae]], [[Pleuronectidae]], [[Paralichthyidae]], and [[Samaridae]]). Some of the better known species that are important in fisheries are:
* Western Atlantic
** [[Gulf flounder]] – ''Paralichthys albigutta''
** [[Paralichthys lethostigma|Southern flounder]] – ''Paralichthys lethostigma''
** [[Summer flounder]] (also known as ''fluke'') – ''Paralichthys dentatus''
** [[Winter flounder]] – ''Pseudopleuronectes americanus''
* European waters
**[[European flounder]] – ''Platichthys flesus''
**[[Witch (righteye flounder)|Witch flounder]] – ''Glyptocephalus cynoglossus''
* North Pacific
** [[Halibut]] – ''Hippoglossus stenolepis''
** [[Olive flounder]] – ''Paralichthys olivaceus''

== Eye migration ==
[[File:Flounder (48797888528).jpg|thumb|upright=1.25|An adult flounder with both eyes migrated to its right, upward-facing side]]
Larval flounder are born with one eye on each side of their head, but as they grow from the larval to juvenile stage through [[metamorphosis]], one eye migrates to the other side of the body. As a result, both eyes are then on the side which faces up. The side to which the eyes migrate is dependent on the species type. As an adult, a flounder changes its habits and [[camouflage]]s itself by lying on the bottom of the ocean floor as protection against predators.<ref>{{cite journal |last1=Fairchild |first1=E.A. |last2=Howell |first2=W.H |title=Factors affecting the post-release survival of cultured juvenile Pseudopleuronectes americanus |journal=Journal of Fish Biology |volume=65 |issue=Supplementary A|pages=69–87 |doi=10.1111/j.0022-1112.2004.00529.x |year=2004 |bibcode=2004JFBio..65S..69F |citeseerx=10.1.1.532.3120 }}</ref>

== Habitat ==
Flounders ambush their prey, feeding at soft muddy areas of the sea bottom, near bridge piles, docks, and coral reefs.

A flounder's diet consists mainly of fish spawn, [[crustacean]]s, [[polychaete]]s and small fish.  Flounder typically grow to a length of {{convert|22|-|60|cm|in|frac=2|sp=us}}, and as large as {{convert|95|cm|in|0|sp=us}}. Their width is about half their length.  Male ''[[Platichthys]]'' have been found up to {{convert|130|km|nmi|round=5|abbr=off}} off the coast of northern Sardinia, sometimes with heavy encrustations of various species of [[barnacle]].

Fluke, a type of flounder, are being  farm raised in open water by Mariculture Technologies in Greenport, New York.<ref>{{cite web|url=https://www.nytimes.com/1996/11/17/nyregion/farming-fluke-in-open-water.html|title=Farming Fluke in Open Water|date=17 November 1996|access-date=26 July 2017|first=Lorraine|last=Kreahling|work=[[The New York Times]]}}</ref>

== Threats ==
[[File:Flounder camo md.jpg|thumb|250px|right|A flounder blending into its environment]]
World stocks of large [[predatory fish]] and large ground fish, including [[Sole (fish)|sole]] and flounder, were estimated in 2003 to be only about 10% of pre-industrial levels, largely due to [[overfishing]]. Most overfishing is due to the extensive activities of the fishing industry.<ref name="Clover2008">{{cite book|first=Charles|last=Clover|title=The End of the Line: How Overfishing is Changing the World and what We Eat|url=https://books.google.com/books?id=OMY-gEKMod8C|year=2008|publisher=University of California Press|isbn=978-0-520-25505-0|oclc=67383509}}</ref><ref name="Myers2003">{{Cite journal | last1 = Myers | first1 = R. A. | last2 = Worm | first2 = B. | doi = 10.1038/nature01610 | title = Rapid worldwide depletion of predatory fish communities | journal = Nature | volume = 423 | issue = 6937 | pages = 280–283 | year = 2003 | pmid =  12748640| bibcode = 2003Natur.423..280M | s2cid = 2392394 }}</ref><ref>{{cite web|url=http://www.bioedonline.org/news/nature-news/save-big-fish/|last=Dalton|first=Rex|date=2006|title=Save the big fish: Targeting of larger fish makes populations prone to collapse|work=BioEd Online|access-date=26 March 2017|archive-date=27 March 2017|archive-url=https://web.archive.org/web/20170327165926/http://www.bioedonline.org/news/nature-news/save-big-fish/|url-status=dead}}</ref><ref>{{cite journal|doi=10.1038/nature05232|pmid=17051218|title=Fishing elevates variability in the abundance of exploited species|journal=Nature|volume=443|issue=7113|pages=859–62|year=2006|last1=Hsieh|first1=Chih-hao|last2=Reiss|first2=Christian S.|last3=Hunter|first3=John R.|last4=Beddington|first4=John R.|last5=May|first5=Robert M.|last6=Sugihara|first6=George|bibcode=2006Natur.443..859H|s2cid=4398663}}</ref> Current estimates suggest that approximately 30 million flounder (excluding [[Sole (fish)|sole]]) are alive in the world today.{{when|date=October 2024}}<ref>{{cite web |title=flounder fish facts |url=https://a-z-animals.com/animals/flounder/ |website=a-z-animals.com}}</ref> In the [[Gulf of Mexico]], along the coast of [[Texas]], research indicates the flounder population could be as low as 15 million due to heavy overfishing and industrial pollution.<ref>{{Cite web |date=October 2000 |title=The Flounder Fishery of the Gulf of Mexico, United States: A Regional Management Plan |publisher=[[Gulf States Marine Fisheries Commission]] |id=Number 83 |url=https://www.gsmfc.org/publications/GSMFC%20Number%20083.pdf }}</ref>

== References ==
{{reflist}}

== External links ==
{{commons category|Pleuronectidae}}
{{Wiktionary|flounder}}
* [http://www.fishbase.org/ComNames/CommonNameSearchList.php?CommonName=flounder Common names containing "flounder"] at [[FishBase]]
* {{YouTube|yutM30Zd3lA|Video of a Fresh Water Flounder}}

{{flatfish}}
{{commercial fish topics}}

[[Category:Commercial fish]]
[[Category:Pleuronectoidei]]
[[Category:Fish common names]]
[[Category:Cuisine of the Southern United States]]
[[Category:Flatfish]]