Flounder

Winter flounder, Pseudopleuronectes americanus

Flowery flounder, Bothus mancus,
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 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
  • Southern flounder - Paralichthys lethostigma
  • Summer flounder (also known as fluke) - Paralichthys dentatus
  • Winter flounder - Pseudopleuronectes americanus
• European waters
  • European flounder - Platichthys flesus
• Northwestern Pacific
  • Olive flounder - Paralichthys olivaceus

Eye migration

In its life cycle, an adult flounder has two eyes situated on one side of its head, while at hatching one eye is located on each side of its brain. One eye migrates to the other side of the body as a process of metamorphosis as it grows from larval to juvenile stage. As an adult, a flounder changes its habits and camouflages itself by lying on the bottom of the ocean floor as protection against predators.^[1] As a result, the eyes are then on the side which faces up. The side to which the eyes migrate is dependent on the species type.

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, crustaceans, polychaetes and small fish. Flounder typically grow to a length of 22–60 centimeters (8.7–23.6 in), and as large as 95 centimeters (37 in). Their width is about half their length. Male Platichthys are known to display a pioneering spirit, and have been found up to 80 miles off the coast of northern Sardinia, sometimes with heavy encrustations of various species of barnacle.

Threats

A flounder blending into its environment

World stocks of large predatory fish and large ground fish, such as 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.^[2][3][4] Current estimates suggest that approximately 30 million flounder (excluding sole) are alive in the world today. 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.

According to Seafood Watch, Atlantic flounders and soles are currently on the list of seafood that sustainability-minded consumers should avoid.^[5]

References

1. ↑ Fairchild, E.A. and Howell, W.H, E. A.; Howell, W. H. (2004). "Factors affecting the post-release survival of cultured juvenile Pseudopleuronectes americanus" (PDF). Journal of Fish Biology. 65 (Supplementary A): 69–87. doi:10.1111/j.0022-1112.2004.00529.x.  July 17, 2004. Accessed 2009-06-08.
2. ↑ Charles Clover (2008). The End of the Line: How Overfishing is Changing the World and what We Eat. University of California Press. ISBN 978-0-520-25505-0. OCLC 67383509. 
3. ↑ Myers, R. A.; Worm, B. (2003). "Rapid worldwide depletion of predatory fish communities". Nature 423 (6937): 280–283. doi:10.1038/nature01610. PMID 12748640. 
4. ↑ "Dalton, Rex. 2006. "Save the big fish: Targeting of larger fish makes populations prone to collapse."". BioEd Online. Retrieved 7 October 2014. 
5. ↑ "Monterey Bay Aquarium: Seafood Watch Program - All Seafood List". Monterey Bay Aquarium. Retrieved 2008-04-17. 

External links

Look up flounder in Wiktionary, the free dictionary.

• Common names containing "flounder" at FishBase
• Video of a Fresh Water Flounder on YouTube

Flatfish Generally larger flatfish Halibut True (2 species) Atlantic halibut Pacific halibut Other Arrowtooth halibut Shotted halibut Greenland halibut Spotted halibut California halibut Bastard halibut Plaice   (4 species) European plaice American plaice Alaska plaice Scale-eye plaice More... Turbot True (1 species) Scophthalmus maximus Spiny (3 species) Psettodidae Other Diamond turbot Hornyhead turbot New Zealand turbot Ocellated turbot Spotted turbot Generally smaller flatfish Sole True (135 species) Common (Dover) sole Finless sole Soleichthys heterorhinos Yellow sole More... American (28 species) Achiridae More... Tongue (138 species) Bengal tongue sole Canary tonguesole Carrot tonguesole Cynoglossus suyeni Durban tonguesole Fourline tonguesole Fourlined tonguesole Ghanaian tonguesole Hooked tonguesole Largescale tonguesole Natal tongue-fish Nigerian tonguesole Ripplefin tonguesole River tonguesole Roundhead toungesole Sand tonguefish Sharpnose tonguesole Southern tongue sole Speckled tonguesole Symphurus thermophilus Three-lined tongue sole More... Other Butter sole Curlfin sole Deepsea sole Dusky sole English sole Flathead sole Lemon sole New Zealand sole Northern rock sole Pacific sand sole Petrale sole Rex sole Rock sole Roughscale sole Slender sole Southern lemon sole Speckled sole Yellowfin sole Other flounder Lefteye (158 species) Crested flounder Flowery flounder Leopard flounder Plate fish Mediterranean scaldfish Twospot flounder Witch More... Righteye (101 species) American smooth flounder Arctic flounder Arrowtooth flounder Banded-fin flounder Barfin flounder Black flounder Blackfin flounder Bering flounder Cleisthenes herzensteini Cleisthenes pinetorum Comb flounder Cresthead flounder Derwent flounder European flounder Far Eastern smooth flounder Flathead flounder Greenback flounder Hypsopsetta macrocephala Indonesian ocellated flounder Kamchatka flounder Large-scale righteye flounder Marbled flounder Marleyella maldivensis Microstomus shuntovi Narrow-body righteye flounder New Zealand flounder Peltorhamphus tenuis Peppered flounder Pseudopleuronectes obscurus Remo flounder Ridged-eye flounder Sakhalin sole Slime flounder Small-mouth righteye flounder Speckled flounder Starry flounder Stone flounder Willowy flounder Winter flounder Witch (righteye) Yellow striped flounder Yellowbelly flounder Yellowtail flounder More... Large tooth (115 species) Anglefin whiff Bigmouth sanddab California halibut Cephalopsetta ventrocellatus Fine flounder Five-eyed flounder Five-rayed sanddab Fourspot flounder Gray flounder Gulf sanddab Horned whiff Longfin sanddab Mimic sanddab Olive flounder Pacific sanddab Peacock flounder Sand whiff Shrimp flounder Small sanddab Speckled sanddab Spotfin flounder Three-eye flounder Thysanopsetta naresi Veracruz whiff More... Southern (6 species) Antarctic armless flounder Armless flounder Finless flounder Paralichthys lethostigma Southern flounder More... Other Citharidae Samaridae Misc   Common dab Chinese brill Deepwater dab Longhead dab New Zealand brill Scale-eye plaice Fluke Related Demersal fish Transitional fossils Amphistium Heteronectes As food Sole meunière Turbot War Predator billfish bonito mackerel salmon shark tuna Forage anchovy herring menhaden sardine shad sprat Demersal cod flatfish pollock ray

Principal commercial fishery species groups Wild Large pelagic fish Mackerel Salmon Saury Shark Swordfish Tuna albacore bigeye Atlantic bluefin Pacific bluefin southern bluefin skipjack yellowfin Forage fish Anchovy Capelin Herring Ilish Menhaden Sardines Shad Sprat european Demersal fish Catfish Cod Atlantic Pacific Alaska pollock Flatfish flounder halibut plaice sole turbot Haddock Mullet Orange roughy Pollock Rockfish Smelt-whitings Toothfish Freshwater fish Carp Sturgeon Tilapia Trout Other wild fish Eel Whitebait more... Crustaceans Crab Krill Lobster Shrimp more... Molluscs Abalone Mussels Octopus Oysters Scallops Squid more... Echinoderms Sea cucumbers Sea urchin more... Farmed Carp bighead common crucian grass silver Catfish Freshwater prawns Gilt-head bream Mussels Oysters Salmon Atlantic salmon trout coho chinook Scallops Seaweed Shrimp Tilapia Commercial fishing World fish production Commercial species Fishing topics Fisheries glossary