Coastal fish

Source: Wikipedia, the free encyclopedia.

Schooling threadfin, a coastal species

Coastal fish, also called inshore fish or neritic fish, inhabit the sea between the

epipelagic zone.[1]
Coastal fish can be contrasted with oceanic fish or offshore fish, which inhabit the deep seas beyond the continental shelves.

Coastal fish are the most abundant in the world.

predator fish that feed on them. Forage fish thrive in inshore waters where high productivity results from upwelling and shoreline run off of nutrients. Some are partial residents that spawn in streams, estuaries and bays, but most complete their life cycles in the zone.[2]

Coastal habitats

  The global continental shelf, highlighted in light blue

Coastal fish are found in the waters above the

shorelines, and around the coral reefs that surround volcanic islands. The total world shoreline extends for 356,000 km (221,000 mi)[3] and the continental shelves occupy a total area of 24.3 million km2 (9 376 million sq mi).[4] This is nearly 5% of the world's total area of 510 million km2.[3]

Nearshore fish

Nearshore fish, sometimes called littoral fish, live close to the shore. They are associated with the

estuaries, lagoons, coral reefs, kelp forests, seagrass meadows
, or rocky or sandy bottoms, usually in shallow waters less than about 10 m (33 ft) deep.

Intertidal fish

Intertidal zones
The rise and fall of tides on a seashore
defines an intertidal zone
Intertidal zones can be a volatile habitat for fish
See also:
tidal pool

Intertidal fish are fish that move in and out with the

rock pools
or under rocks.

The

molluscs such as the common limpet and the common periwinkle can be permanent residents of rock pools. But most rock pool animals, such as crabs, shrimp
and fish are just temporary residents, occupying a rock pool only until the next tide takes them to a new location.

Some rock pool fish which are temporary residents include the

lumpsucker. However some other rock pool fish are territorial in nature, and will stay with the same pool for extended periods. Examples are the common blenny and its near relative the butterfish
.

  • The common
    blenny, also known as the shanny, is found in northern temperate waters. They hide under rocks and in crannies in rock pools when the tide is out. They feed on green seaweed and invertebrates such as barnacles. They can crawl on dry land, using their paired fins. About 16 cm (6.3 in) long, they have smooth skin, without scales, and are covered with soft slime. The slime prevents them drying if they are stranded on a shore between tides. So long as their skin stays moist, they can breathe out of water. They are sometimes called "sea frogs" because they bask in the sun on weeds outside the water, and like frogs, jump to safety when disturbed. They can change their colour to match their surroundings. The female lays eggs in crevices or under stones and the male guards them until they hatch. In the winter, when storms can be severe, they move out of their rock pools into the shallows. The common blenny is bold with strong teeth, and will bite humans if it feels threatened.[6]
  • The rock goby is a small fish, about 12 cm (4.7 in), found in northern temperate waters. It is coloured black with white blotches, and hides under stones and amongst seaweed. It is a temporary resident of rock pools when the tide is out. The female rock goby lays eggs on the underside of rocks and shells and then leaves them. The male guards the eggs until they hatch. First-year rock gobies often visit rock pools in winter when the older fish have left.
  • Australian blenny
    Australian
    blenny
  • Rock goby
    Rock goby
  • Long-spined sea scorpion[7]
    Long-spined sea scorpion[7]
  • Smooth lumpsucker inflated in a defensive response
    Smooth
    lumpsucker
    inflated in a defensive response
  • The
    long-spined sea scorpion
    , a small stout fish which grows about 29 cm (11 in) long, is another temporary resident of rocky pools. They have large black eyes, a large mouth, and four long spines—two on each side on the gill cover—that stick out when the fish is removed from the water. They also have an organ like a finger on each side of their mouths which helps them catch prey. Because of their broad heads, they are also called "bullheads". They have a variety of effective camouflaged colours ranging from shades of browns with cream blotches, to orange and red with white blotches. They can also change their body colour to match their surroundings. They are found around the coasts of Northern Europe in shallow rocky waters hiding amongst seaweed. They are also found in rock pools and sometimes in waters 30 m (98 ft)deep. Long-spined sea scorpions lay eggs amongst seaweed or attached to rock crevices. The young hatch after two or three weeks, and go through several development stages before maturing into adults.
  • Lumpsuckers
    are found in temperate northern waters. They live on the seafloor, and are temporary residents of rocky pools in late winter and early spring when they spawn. The body of the lumpsucker is scaleless and covered with small lumps. They have a large sucking disc on their underside which they use to cling to surfaces. They are normally a blue to slate-grey colour, and are effectively camouflaged to look like stones. They are portly, nearly spherical, poor swimmers, reaching lengths up to 50 cm (20 in). After the female lumpsucker lays eggs, the male takes over, clamping itself to a rock where it guards the eggs. When they hatch, lumpsuckers look like tiny tadpoles. They remain in shallow water and rock pools, hiding amongst seaweed and rocks, until they grow up.

Estuarine fish

land runoff, river mouths and estuary waters can be turbid and nutrient rich, sometimes to the point of eutrophication
.
See also: estuary, mangrove, and brackish water

Estuaries are partly enclosed coastal bodies of water with one or more rivers or streams flowing into them, and with a free connection to the open sea.[8] These brackish water habitats form a transition zone between river environments and ocean environments, and ecological successions can form along the way. Estuaries are subject to both marine influences, such as tides, waves, and the influx of saline water; and riverine influences, such as flows of fresh water and sediment. The inflow of both seawater and freshwater provide high levels of nutrients in both the water column and sediment, making estuaries productive natural habitats.[9]

Fishes that spend time in

diversity in the estuary.[10]

River estuaries form important staging points during the migration of anadromous and catadromus fish species, such as salmon and eels, giving them time to form social groups and to adjust to the changes in salinity. Salmon are anadromous, meaning they live in the sea but ascend rivers to spawn; eels are catadromous, living in rivers and streams, but returning to the sea to breed. Besides the species that migrate through estuaries, there are many other fish that use them as "nursery grounds" for spawning or as places young fish can feed and grow before moving elsewhere. For example, herring and plaice are two commercially important species that use the Thames Estuary for this purpose.

archer fish, perch-like fish that "spit" at insects and other small animals living in the trees, knocking them into the water where they can be eaten. Like estuaries, mangrove swamps are important breeding grounds for many fish, with species such as snappers, halfbeaks, and tarpon
spawning or maturing among them.

Coral reef fish

paradoxically in clear, low nutrient waters, along tropical continental coasts and around volcanic islands. Coral reef fish
are numerous and diverse.
Main article: Coral reef fish

In tropical waters, coral reef fish live amongst or in close relation to coral reefs. Coral reefs form complex ecosystems with tremendous biodiversity. Coral reef fish can be particularly colourful and interesting to watch. Hundreds of species can exist in a small area of a healthy reef, many of them hidden or well camouflaged. Reef fish have developed many ingenious specialisations adapted to survival on the reefs. Coral reefs occupy less than one per cent of the surface area of the world oceans, yet they provide a home for 25 per cent of all marine fish species.

Coral reefs often depend on other habitats in the surrounding area for the supply of nutrients, such as seagrass meadows and mangrove forests. Seagrass and mangroves supply dead plants and animals which are rich in nitrogen and also serve to feed fish and animals from the reef by supplying wood and vegetation. Reefs in turn protect mangroves and seagrass from waves and produce sediment for the mangroves and seagrass to root in.[11]

anthias
. They are hermaphrodite, and swim in "harems".

protogynous hermaphrodites
. All anthias are born female; if a dominant male perishes, the largest female of the group will often change into a male to take its place. This may lead to squabbling between the next largest male and the transforming female, whose hormones are now surging with testosterone. This can turn quite vicious in the limited confines of captivity.

The foureye butterflyfish has a false eyespot on its sides, which can confuse prey and predators

coralfish. They are widespread on coral reefs. Butterflyfish are mostly between 12 and 22 centimetres (4.7 and 8.7 in) in length. The largest species, the lined butterflyfish and saddle butterflyfish, grow to 30 centimetres (12 in). Many species are brightly coloured and strikingly patterned, though other species are dull in colour. Many have eyespots on their flanks and dark bands across their eyes, not unlike the patterns seen on butterfly wings.[12]: 184  Their deep, laterally narrow bodies are easily noticed through the profusion of reef life. The conspicuous colouration of butterflyfish may be intended for interspecies communication. Butterflyfish have uninterrupted dorsal fins with tail fins that may be rounded or truncated, but are never forked. Generally diurnal and frequenting waters of less than 18 metres (59 ft) (though some species descend to 180 metres (590 ft)), butterflyfish stick to particular home ranges. The corallivores are especially territorial, forming mated pairs and staking claim to a specific coral head. Contrastingly, the zooplankton feeders form large conspecific groups. By night butterflyfish hide in reef crevices and exhibit markedly different colouration. Their colouration also makes butterflyfish popular aquarium fish. However, most species feed on coral polyps and sea anemones
, which can result in problems for the hobby aquarists.

farmerfish.[12] Different species display a wide range of colours, although some are relatively drab. Pomacentrids are omnivorous or herbivorous, feeding off algae, plankton, and small bottom-dwelling crustaceans. A small number eat coral.[12]

blue-striped snappers

brackish water, so they do not enter estuaries or the mouths of rivers
.

Other nearshore fish

Kelp forests can provide shelter and food for shallow water fish

Other nearshore or shallow water fish live near the shore in depths of less than 10 metres. They occupy the areas over sandy or rocky bottoms, and can be associated with seagrass meadows and kelp forests. They can be divided into demersal fish and pelagic fish. Demersal fish live on or near the sea floor, while pelagic fish live in the water column away the sea floor.

Examples of such shallow water demersal fish, found in both tropical and temperate waters around the world, are triplefins, seahorses, wrasse and flounder. As demersal fish, all these fish spend most of their time on or near the sea floor.

Examples of shallow water pelagic fish, found in both tropical and temperate waters around the world, are grey mullet, sprats and garfish. As pelagic fish, all these fish spend most of their time living in the water column away the sea floor.

  • The
    seine nets
    .
  • The garfish is a long, slender fish, looking like a spear, which feeds on seagrass fragments, shrimps and crab larvae. In turn it is preyed on by larger fish and, since it is often near the surface, cormorants and gannets.

Coastal pelagic fish

Plankton feeding

See also: Pelagic fish § Forage fish, and Shoaling and schooling
marine food chain
(typical)
  Sun
↓
phytoplankton
↓
herbivorous zooplankton
↓
carnivorous zooplankton
↓
  filter feeder
↓
  predatory vertebrate
World distribution of plankton
Areas of upwelling in red

At the base of

carbon fixation, so they are mainly located in sunlit surface waters. Phytoplankton also need and rapidly use nutrients in the water column.[18] The phytoplankton are eaten by zooplankton, which in turn are eaten by predatory zooplankton. Filter feeders then eat the plankton and larger predatory fish eat the filter feeders (see diagram at the right).[19]

Most filter-feeding pelagic fish found in coastal waters are small, silvery

fry (recently hatched fish), often by filter feeding. In turn, they are preyed on by larger predatory fish, seabirds and marine mammals
.

Worldwide, there are five major coastal currents associated with upwelling areas: the

overfished
.

Predatory

Predator bluefin trevally sizing up schooling anchovies
See also: Pelagic fish § Predator fish

Predatory pelagic fishes found on continental shelves worldwide in both tropical and temperate waters include

porgies, barracuda, amberjacks and cutlassfishes. They tend to be larger fish, and are carnivorous, feeding on the smaller, silvery forage fish
that eat plankton (see section above). Some species also feed on crabs and other invertebrates, foraged from the sea floor.

The sand tiger shark is a large coastal shark that inhabits coastal waters worldwide. Its numbers are declining, and it is now listed as a vulnerable species on the IUCN Red List.[22]
gamefish found in Indo-Pacific tropical waters. They are powerful apex predators
in most of their habitats, hunting both individually and in schools.

Demersal pelagic fish

Main article: Demersal fish
morid cod have a barbel
(fleshy filament) on their lower jaw which they use to detect prey buried in the sand or mud.

Fish that live on or in close association with the sea floor are called demersal fish. This section discusses the coastal demersal fish that live on the continental shelf, but are living further from the coast and in deeper water than the nearshore fish discussed above.

Demersal fish are

benthic fish (flatfish) such as plaice
which live on the sea bed. Benthic fish tend to be "flat", so they can lie on the bottom.

  • The polar cod is found further north than any other fish species. It frequents river mouths and feeds on plankton and krill. It is preyed on by narwhals, belugas, ringed seals and seabirds.[25]
    The
    belugas, ringed seals and seabirds.[25]
  • The John Dory is so thin it can hardly be seen from the front. The large eyespot on the side of its body confuses its prey.[26]
    The John Dory is so thin it can hardly be seen from the front. The large eyespot on the side of its body confuses its prey.[26]
  • The turbot is a large left-eyed flatfish usually found not too far from shore in sandy shallow waters. It is a prized food fish.[27]
    The
    food fish.[27]
  • The red gurnard is a mail-cheeked fish found to depths of around 180 metres. They often grunt when captured as air is expelled from its air bladder.[28]
    The red gurnard is a mail-cheeked fish found to depths of around 180 metres. They often grunt when captured as air is expelled from its air bladder.[28]
The stargazer is an ambush predator which can deliver both venom and electric shocks. It has been called "the meanest thing in creation".[29]

electric shocks. They are ambush predators with eyes on top of their heads (thus the name). Stargazers also have a large upward-facing mouth in a large head. They bury themselves in sand with only their eyes showing, and leap upwards to ambush fish and invertebrates overhead. Some species have a worm-shaped lure growing out of the floor of the mouth, which they wiggle to attract prey's attention. Lengths range from 18 cm up to 90 cm, for the giant stargazer Kathetostoma giganteum. Stargazers are a delicacy in some cultures. The venom is destroyed when it is cooked, and stargazers are sold in some fish markets with their electric organ removed. They have been called "the meanest things in creation" and the "worst pet on earth".[29][30]
  • gill nets (in earlier times longlines
    were used).
  • Wreckfish are a family Polyprionidae of perciform fishes, found on the floor of the continental shelf and slope where they inhabit caves and shipwrecks (thus their common name). The Atlantic wreckfish is at depths between 40 and 600 m (130 and 1,970 ft). They are largely a solitary fish, though juveniles school below floating objects. Their diet includes large ocean cephalopods, crustaceans, and other bottom-dwelling fishes.

See also

Notes

  1. ^ Moyle and Cech, 2004, page 585
  2. ^ a b Moyle and Cech, 2004, page 572
  3. ^ a b World The World Factbook, CIA. Retrieved 26 February 2010.
  4. ^ Continental shelf areas Archived December 2, 2008, at the Wayback Machine Earth trends. Retrieved 25 February 2010.
  5. ^ Froese, Rainer; Pauly, Daniel (eds.) (2010). "Penetopteryx nanus" in FishBase. March 2010 version.
  6. ^ Shanny (common blenny) Archived 2012-07-04 at the Wayback Machine BBC. Updated July 2005.
  7. ^ Froese, Rainer; Pauly, Daniel (eds.) (2010). "Cottus bubalis" in FishBase. March 2010 version.
  8. ^ Pritchard, D. W. (1967) What is an estuary: physical viewpoint. p. 3–5 in: G. H. Lauf (ed.) Estuaries, A.A.A.S. Publ. No. 83, Washington, D.C.
  9. ISBN 0-19-852508-7
  10. ^ Moyle and Cech, 2003, p. 50.
  11. ^ Greenpeace Book of Coral Reefs
  12. ^ a b c d e f g h i j k l Johnson, G.D.; Gill, A.C. (1998). Paxton, J.R.; Eschmeyer, W.N. (eds.). Encyclopedia of Fishes. San Diego: Academic Press.
    ISBN 0-12-547665-5
    .
  13. ^ Froese, Rainer, and Daniel Pauly, eds. (2007). "Pomacentridae" in FishBase. July 2007 version.
  14. ISBN 978-0-87666-034-8
    .
  15. ISBN 978-0-471-25031-9
    .
  16. ^ Jenkins, A.P.; G.R. Allen (2002). "Neopomacentrus aquadulcis, a new species of damselfish (Pomacentridae) from eastern Papua New Guinea". Records of the Western Australian Museum. 20: 379–382.
  17. doi:10.11646/zootaxa.1671.1.2. Archived from the original
    (PDF) on 21 July 2011. Retrieved 1 March 2010.
  18. ^ Anderson, G (2003) Coral Reef Formation Marine Science.
  19. ^
    ISBN 1-4051-1118-6
  20. ^ Porgy Encyclopædia Britannica. Retrieved February 23, 2010.
  21. ^ Pollnac, R.B. 1998 Aspects of the human ecology of the coral reefs of Discovery Bay. p. 141-199. In R.B. Pollnac (ed.) Rapid assessment of management parameters for coral reefs. Coastal Resources Center, University of Rhode Island. CMR 2205, ICLARM 1445.
  22. doi:10.2305/IUCN.UK.2009-2.RLTS.T3854A10132481.en
    .
  23. ^ "John dory".
  24. ISBN 1-84309-666-8
    .
  25. ^ Froese, Rainer; Pauly, Daniel (eds.) (2010). "Boreogadus saida" in FishBase. March 2010 version.
  26. ^ Froese, Rainer; Pauly, Daniel (eds.) (2010). "Zeus faber" in FishBase. March 2010 version.
  27. ^ Froese, Rainer; Pauly, Daniel (eds.) (2010). "Psetta maxima" in FishBase. March 2010 version.
  28. ^ Walrond, Carl (2009) "Coastal fish - Fish of the open sea floor" Te Ara - the Encyclopedia of New Zealand. Updated 2 March 2009.
  29. ^ a b Grady, Denise Venom Runs Thick in Fish Families, Researchers Learn The New York Times 22 August 2006.
  30. ^ Froese, Rainer; Pauly, Daniel (eds.) (2010). "Uranoscopus sulphureus" in FishBase. March 2010 version.
  31. ^ Froese, Rainer; Pauly, Daniel (eds.) (2010). "Parapercis hexophtalma" in FishBase. March 2010 version.

References

External links
Retrieved from "https://en.wikipedia.org/w/index.php?title=Coastal_fish&oldid=1190193480"