Instruct: Given a question, retrieve passages that can help answer the question.
Query: What is the most abundant fish species in the Indian ocean?
The abundant sea harvest of the Indian Ocean around the Atolls of the Maldives and, Lakshadweep in India yields many pelagic fishes, like skipjack, yellowfin tuna, little tunny (known locally as laṭṭi) and frigate mackerel. All these fishes have been traditionally processed on the Maldive Islands as a main source of food as well as income for Maldivians.
Madagascar lies entirely in the Indian Ocean Whale Sanctuary, a whale sanctuary that covers the Indian Ocean south to 55º S. The sanctuary prohibits commercial whaling and aims to facilitate the recovery of whale populations, allow whales to do their jobs within the ecosystem, and foster public awareness. This sanctuary’s conservation efforts are uniquely important for several reasons. The sanctuary allows for the Sperm whale and the Oman Humpback whale to recover their population which has been diminished by illegal soviet whaling operations in the 70’s. The sanctuary also allows the population recovery of the Bryde’s whale from Japanese whaling operations which still continue to this day as Japan does not respect the sanctuary and continues its operations claiming that their operations are purely scientific. Approximately 600 whales are killed each year by Japanese scientific whaling operations.
A study conducted by Scripps Institution of Oceanography showed that the average plastic content in the stomachs of 141 mesopelagic fish over 27 different species was 9.2%. Their estimate for the ingestion rate of plastic debris by these fish in the North Pacific was between 12000 and 24000 tons per year. The most popular mesopelagic fish is the lantern fish. It resides in the central ocean gyres, a large system of rotating ocean currents. Since lantern fish serve as a primary food source for the fish that consumers purchase, including tuna and swordfish, the plastics they ingest become part of the food chain. The lantern fish is one of the main bait fish in the ocean, and it eats large amounts of plastic fragments, which in turn will not make them nutritious enough for other fish to consume.
The diet of "Pteranodon" is known to have included fish; fossilized fish bones have been found in the stomach area of one "Pteranodon", and a fossilized fish bolus has been found between the jaws of another "Pteranodon", specimen AMNH 5098. Numerous other specimens also preserve fragments of fish scales and vertebrae near the torso, indicating that fish made up a majority of the diet of "Pteranodon" (though they may also have taken invertebrates).
This rail forages in shallow water near cover and eats mainly aquatic insects and crustaceans. It forages by probing the mud while moving around in shallow water.
Atlantic wolffish use their strong jaws to eat hardshell molluscs, crustaceans, and echinoderms. They do not eat other fish. They are known to frequently eat large whelks ("Buccinum"), cockles ("Polynices", "Chrysodomus" and "Sipho"), sea clams ("Mactra"), large hermit crabs, starfish, sea urchins. They are an important predator of sea urchins and green crabs, whose populations escalate rapidly and can negatively affect the health of a marine system.
"Phytoplankton are eaten by zooplankton - small animals which, like phytoplankton, drift in the ocean currents. The most abundant zooplankton species are copepods and krill: tiny crustaceans that are the most numerous animals on Earth. Other types of zooplankton include jelly fish and the larvae of fish, marine worms, starfish, and other marine organisms". In turn, the zooplankton are eaten by filter-feeding animals, including some seabirds, small forage fish like herrings and sardines, whale sharks, manta rays, and the largest animal in the world, the blue whale. Yet again, moving up the foodchain, the small forage fish are in turn eaten by larger predators, such as tuna, marlin, sharks, large squid, seabirds, dolphins, and toothed whales.
Ommastrephinae includes the largest species of squids belonging to the family Ommastrephidae, Humboldt squid ("Dosidicus gigas") which can grow to in mantle length (ML). It also contains the smallest squid species belonging to the family, the glass squid ("Hyaloteuthis pelagica") which has a mantle length of only up to . Ommastrephinae are mostly pelagic members of the family Ommastrephidae. All species of this subfamily contain photophores whose locations vary by species. Some species of the subfamily (notably "Sthenoteuthis" and "Ommastrephes") are known for their behavior of leaping out of the water (hence the common names 'flying squid').
The Bhitarkanika Mangroves are home to 55 of India's 58 known mangrove species. The mangroves harbor one of India's largest populations of saltwater crocodiles, and Gahirmatha Beach, which separates the mangroves from the Bay of Bengal, is the world's most important nesting beach for olive ridley sea turtles. Some wildlife experts are of the opinion that the largest saltwater crocodile ever was in Bhitarkanika, measuring an estimated 23 feet (7.0 m) which could be traced from the skull preserved by the Kanika Royal Family. The crocodile was shot near Dhamara in 1926, and later its skull was preserved by the then Kanika King. Crocodile experts estimate the animal to have been between 20 feet (6.1 m) and 23 feet (7.0 m) long, as the size of the skull was measured one ninth of the total length of the body. In 2006 the park was recognized by the "Guinness Book of World Records" for the largest white crocodile living in captivity also measuring 23 feet. The wetland also hosts a large and diverse population of resident and migratory birds. Rhesus monkey, leopard cat, fishing cat, jungle cat, small Indian civet cat, toddy cat, common mongoose, jackal, striped hyena, Indian fox, wild pig, Indian porcupine, mole rat, long tailed tree mouse, spotted deer, sambar, common otter, smooth Indian otter are also found here.
Although the BCLME holds significant aquaculture potential, the industry is underdeveloped. South Africa’s aquaculture industry is the most productive of the three countries’. It produces abalone, mussels, oysters, seaweed and prawns, with abalone the most important of these in terms of volume and employment. In Namibia, mussels, oysters, "Gracilaria" (red seaweed used by the pharmaceutical industry) and abalone are farmed, but the aquaculture industry is dominated by oyster production.
Sea urchins or urchins () are typically spiny, globular animals, echinoderms in the class Echinoidea. About 950 species live on the seabed, inhabiting all oceans and depth zones from the intertidal to . Their tests (hard shells) are round and spiny, typically from across. Sea urchins move slowly, crawling with their tube feet, and sometimes pushing themselves with their spines. They feed primarily on algae but also eat slow-moving or sessile animals. Their predators include sea otters, starfish, wolf eels, and triggerfish.
The knifetooth sawfish ("Anoxypristis cuspidata"), also known as the pointed sawfish or narrow sawfish, is a species of sawfish in the family Pristidae, part of the Batoidea, a superorder of cartilaginous fish that includes the rays and skates. Sawfish display a circumglobal distribution in warm marine and freshwater habitats. Their extant biodiversity is limited to five species belonging to two genera (Pristis and Anoxypristis). The sawfishes are characterised by the long, narrow, flattened rostrum or extension on their snout. This is lined with sharp transverse teeth, arranged in a way that resembles the teeth of a saw. It is found in the shallow coastal waters and estuaries of the Indo-West Pacific, ranging from the Red Sea and the Persian Gulf to southern Japan, Papua New Guinea and northern Australia. It is the only living member of the genus Anoxypristis, but was previously included in the genus "Pristis". Compared to that genus, "Anoxypristis" has a narrower rostral saw with numerous teeth on the distal part and no teeth on the basal one-quarter (toothless section about one-sixth in juveniles). This endangered species reaches a length of up to .
Deraniyagala's beaked whale is known from only seven individuals that have stranded themselves on beaches of various islands in the Indian and South Pacific Oceans: Seychelles, Maldives, Sri Lanka, Gilbert Islands, Kiribati and Line Islands. It is thought that, like Cuvier's beaked whale, they live in insular populations (isolated communities).
Nearly 100 species of reptiles occur in the Eastern Ghats. Many endangered species are also present, including the mugger crocodile "(Crocodylus palustris)", Indian black turtle "(Melanochelys trijuga)", Indian flapshell turtle "(Lissemys punctata)", Indian tent turtle "(Pangshura tentoria)", Indian star tortoise "(Geochelone elegans)", Leith's softshell turtle "(Nilssonia leithii)", many of which are found in the northern rivers and riverine valley tracts.
The known diet of the dusky shark encompasses pelagic fishes, including herring and anchovies, tuna and mackerel, billfish, jacks, needlefish and flyingfish, threadfins, hairtails, lancetfish, and lanternfish; demersal fishes, including mullets, porgies, grunts, and flatheads, eels, lizardfish, cusk eels, gurnards, and flatfish; reef fishes, including barracudas, goatfish, spadefish, groupers, scorpionfish, and porcupinefish; cartilaginous fishes, including dogfish, sawsharks, angel sharks, catsharks, thresher sharks, smoothhounds, smaller requiem sharks, sawfish, guitarfish, skates, stingrays, and butterfly rays; and invertebrates, including cephalopods, decapod crustaceans, barnacles, and sea stars. Very rarely, the largest dusky sharks may also consume sea turtles, marine mammals (mainly as carrion), and human refuse.
Atlantic herring ("Clupea harengus") is a herring in the family Clupeidae. It is one of the most abundant fish species in the world. Atlantic herrings can be found on both sides of the Atlantic Ocean, congregating in large schools. They can grow up to in length and weigh up to . They feed on copepods, krill and small fish, while their natural predators are seals, whales, cod and other larger fish.
Swells dropped to 1–1.5 m on 28 June 2011, allowing more netting of sardines. Sardines were netted at Amanzimtoti; on the main beach and at Chain Rocks. A 22-year-old American marine biology student (research diver) named Paulo Edward Stanchi was attacked by a large dusky shark while diving at Aliwal Shoal Marine Protected Area. The group of divers had encountered a pocket of sardines when a 3 m long dusky shark bit Mr Stanchi on his left leg and hands. Mr Stanchi managed to free himself from the shark, and was treated on the diving boat before being transported to Rocky Bay, where medics stabilised him. He was then airlifted to Nkosi Albert Luthuli Hospital, where he underwent surgery. Dusky sharks generally live offshore, but come closer to the shore during the sardine run. The annual sardine run allowed more dusky sharks in the Aliwal Shoal MPA than usual, but there was no reason for them to show any more interest in divers than usual. Mr Stanchi had been wearing split fins with black and grey stripes, and this may have looked like a small shoal of fish to the shark. Meanwhile, a woman in her 40s broke her leg in the frenzy at Amanzimtoti when the sardines were netted. The woman is believed to have been trying to get some of the sardines when she "stepped wrong" and fractured her leg. Paramedics stabilized her before transporting her to hospital.
The IWC has designated two whale sanctuaries: the Southern Ocean Whale Sanctuary, and the Indian Ocean Whale Sanctuary. The Southern Ocean whale sanctuary spans and envelopes Antarctica. The Indian Ocean whale sanctuary takes up all of the Indian Ocean south of 55°S. The IWC is a voluntary organization, with no treaty. Any nation may leave as they wish; the IWC cannot enforce any law it makes.
Sea urchins are established in most seabed habitats from the intertidal downwards, at an extremely wide range of depths. Some species, such as "Cidaris abyssicola", can live at depths of several thousands metres. Many genera are only found in the abyssal zone, including many cidaroids, most of the genera in the Echinothuriidae family, and the "cactus urchins" "Dermechinus". One of the deepest-living families is the "Pourtalesiidae", strange bottle-shaped irregular sea urchins that live only in the hadal zone and have been collected as deep as 6850 metres beneath the surface in the Sunda Trench. Nevertheless, this makes sea urchin the class of echinoderms living the least deep, compared to brittle stars, starfish and crinoids that remain abundant below and sea cucumbers which have been recorded from .
The heaviest known cephalopod, and the largest living invertebrate, is the colossal squid. The largest recorded specimen of this species, caught in the Ross Sea in 2007, weighed . However, its beak is not the largest known from this species; even bigger colossal squid beaks have been recovered from the stomachs of sperm whales, indicating that this species can grow larger still.
Some species of sea urchins, such as the slate pencil urchin ("Eucidaris tribuloides"), are commonly sold in aquarium stores. Some species are effective at controlling filamentous algae, and they make good additions to an invertebrate tank.
The Pillar Point Harbor at the northern edge of Half Moon Bay offers a protected landing for boats and provides other marine infrastructure. In the late 1980s a new master plan was developed for the Harbor. A variety of fish species have been identified in the harbor area. The most abundant fish include flatfish, particularly the speckled sanddab (Citharichthys stigmaeus) and the commercially important English sole (Parophrys vetulus), several species of rockfish (Sebastes sp.) with boccacio (S. paucispinis) most abundant, many members of the surfperch family, the most abundant being shiner (Cymanogaster aggregata) and dwarf surfperches (Micrometrus minimus), and the commercially important Pacific herring (Clupea harengus). Smaller populations of many other species, including significant commercial or sport species such as various surfperch, flatfish including halibut (Paralichthys californicus), lingcod (Ophiodon elongatus), and cabezon (Scoraenichthys marmotarus) also are found in the harbor during the summer. Abundant winter species include starry flounder (Platichthys stellatus) and topsmelt (Atherinops affinis). At Pillar Point Harbor, fishermen sell crab and fish catches straight off their boats at discount prices directly to the public, and restaurants will fillet the fish for purchasers.
Found in the Pacific Ocean from Japan and Baja California to the Bering Sea, it is the most common species of lanternfish in the northwestern Pacific, and one of the most abundant larval fish in the California Current. Like all lanternfish, this is a deep sea species; it spends the day in the ocean's deeper bathypelagic and mesopelagic zones and ascends to or near the ocean's surface during the night. It is a cool-water fish.
Among the tropical oceans, the western Indian Ocean hosts one of the largest concentration of phytoplankton blooms in summer, due to the strong monsoon winds. The monsoonal wind forcing leads to a strong coastal and open ocean upwelling, which introduces nutrients into the upper zones where sufficient light is available for photosynthesis and phytoplankton production. These phytoplankton blooms support the marine ecosystem, as the base of the marine food web, and eventually the larger fish species. The Indian Ocean accounts for the second largest share of the most economically valuable tuna catch. Its fish are of great and growing importance to the bordering countries for domestic consumption and export. Fishing fleets from Russia, Japan, South Korea, and Taiwan also exploit the Indian Ocean, mainly for shrimp and tuna.
About 510 (23%) of the 2,200 fin fish species in Indian waters are found in the Gulf, making it the most highly diverse fish habitat in India. Coral associated ornamental fishes belonging to the family Chaetodontidae, (butterfly fish); Parrotfish; Amphiprion spp (clown fish), Holocentrus spp (squirrel fish), Scarus spp (parrot fish), Lutjanus spp (snappers) and Abudefduf saxatilis (sergeant Major) are abundant.