Indian oil sardine | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Clupeiformes |
Family: | Dorosomatidae |
Genus: | Sardinella |
Species: | S. longiceps |
Binomial name | |
Sardinella longiceps Valenciennes, 1847 | |
The Indian oil sardine (Sardinella longiceps) is a species of ray-finned fish in the genus Sardinella . It is one of the two most important commercial fishes in India (with the mackerel). [2] The Indian oil sardine is one of the more regionally limited species of Sardinella and can be found in the northern regions of the Indian Ocean. These fish feed on phytoplankton (diatoms) and zooplankton (copepods). [3]
The body of these Sardinella is particularly elongated even to the point of being subcylindrical. They have a slightly rounded belly and have eight rays on their pelvic fins. They have a very large number of gill rakers and a faint golden spot behind the gill opening. They also have a faint golden midlateral line, as well as a black spot on the hind border of their gill covers. [3]
S. longiceps attains sexual maturity around 15 cm and 1 year of age. The lifespan of this fish is about 2.5 years, but difficult to determine because the annual rings in their scales may be formed for several reasons other than yearly changes in their environment. Only after the first year are the rings a reliable indicator of age, because they may be formed due to the reduced feeding activity associated with planktonic scarcity during the rise in temperature of the environment in summer. An experiment was done by measuring scales from a selected body area, and then determining the relationship between the fish length and scale length. According to these tests, the average lengths for each ring were 14.3, 16.4, and 18.4 cm at the age of one, two, and three years, respectively. [2]
The movement of the fish was determined to be less seasonal than dependent on water conditions directly before and after the monsoon season. This affects the spawning season and means that it may vary from any period between June and December. These fish only spawn once during the spawning season. The distribution of the fish throughout the spawning season is determined by the size and age of the fish. Many of the oldest, most mature adults between 17 and 19 cm spawn early in the season, while the juveniles of S. longiceps arrive to spawn later in the season. The peak period for commercial catch is June and July, when the juvenile fish have fattened themselves to prepare for their first spawning season. Rarely does S. longiceps survive a second spawn, but this is much more common in females.
Ovary development is classified in stages I-VI. Stages IV, V, and VI are able to spawn. Fish at stage IV have ovaries that fill two-thirds of their available body cavity. By stage VI, these ovaries fill the body cavity and are made up of large transparent ripe eggs. These fish only spawn once in a spawning season and produce around 75,000 eggs. The development of the egg requires only 24 hours. These eggs are spherical and range from 1 to 4 mm in diameter. These fish are called oil sardines because an oil globule makes up a major part of the egg yolk. These fish have 53 myotomes in the larval stage, but adults have only 46-48 vertebrae.
The first day of development includes minimal movement, but it travels by serpentine swimming. By the end of this first day, the oil globule in the yolk disappears or is used up. On the second day of development, the pigmentation of the larva is stable and the eye coloration stabilizes to a silvery white sheen. During the third day, the yolk is completely used up. [4]
Sardine and pilchard are common names for various species of small, oily forage fish in the herring suborder Clupeoidei. The term 'sardine' was first used in English during the early 15th century; a somewhat dubious etymology says it comes from the Italian island of Sardinia, around which sardines were once supposedly abundant.
The Atlantic mackerel, also known as Boston mackerel, Norwegian mackerel, Scottish mackerel or just mackerel, is a species of mackerel found in the temperate waters of the Mediterranean Sea, the Black Sea, and the northern Atlantic Ocean, where it is extremely common and occurs in huge shoals in the epipelagic zone down to about 200 m (660 ft). It spends the warmer months close to shore and near the ocean surface, appearing along the coast in spring and departing with the arrival of colder weather in the fall and winter months. During the fall and winter, it migrates out into deeper and more southern water, seeking warmer temperatures.
The ciscoes are salmonid fish that differ from other members of the genus Coregonus in having upper and lower jaws of approximately equal length and high gill raker counts. These species have been the focus of much study recently, as researchers have sought to determine the relationships among species that appear to have evolved very recently. Cisco is also specifically used for the North American species Coregonus artedi, also known as lake herring.
The crevalle jack, also known as the common jack, black-tailed trevally, couvalli jack, black cavalli, jack crevale, or yellow cavalli is a common species of large marine fish classified within the jack family, Carangidae. The crevalle jack is distributed across the tropical and temperate waters of the Atlantic Ocean, ranging from Nova Scotia, Canada to Uruguay in the western Atlantic and Portugal to Angola in the eastern Atlantic, including the Mediterranean Sea. It is distinguishable from similar species by its deep body, fin colouration and a host of more detailed anatomical features, including fin ray and lateral line scale counts. It is one of the largest fish in the genus Caranx, growing to a maximum known length of 124 cm and a weight of 32 kg, although is rare at lengths greater than 60 cm. The crevalle jack inhabits both inshore and offshore waters to depths of around 350 m, predominantly over reefs, bays, lagoons and occasionally estuaries. Young fish dispersed north by currents in the eastern Atlantic are known to migrate back to more tropical waters before the onset of winter; however, if the fish fail to migrate, mass mortalities occur as the temperature falls below the species' tolerance.
The goldstripe sardinella or goldstripe sardine is a species of fish of the family Clupeidae. It is native to shallow tropical waters of the western Indo-Pacific, living at depths down to 70 m, and being associated with coral reefs. It grows up to 17 cm in length and forms large schools.
The slender rainbow sardine is a small, subtropical, salt water fish of the Indian Ocean and the South China Sea which was first described by Bleeker in 1849. Dussumieria hasselti and Dussumieria productissima are synonyms for this same fish. It is a round herring of the family Clupeidae.
Sardinella is a genus of fish in the family Dorosomatidae found in the Atlantic, Indian and Pacific Ocean. They are abundant in warmer waters of the tropical and subtropical oceans. Adults are generally coastal, schooling, marine fish but juveniles are often found in lagoons and estuaries. These species are distinguished by their ranges and by specific body features, but they are often confused with one another. Fish of the genus have seven to 14 striped markings along the scales of the top of the head. The paddle-shaped supramaxilla bones are characteristic; they separate Sardinella from other genera and their shapes help distinguish species. They have paired predorsal scales and enlarged fin rays.
The leopard coral grouper, also known as the common coral trout, leopard coral trout, blue-dotted coral grouper or spotted coral grouper, is a species of marine ray-finned fish, a grouper from the subfamily Epinephelinae which is part of the family Serranidae, which also includes the anthias and sea basses. It is found in the Western Pacific Ocean.
The northern whiting, also known as the silver whiting and sand smelt, is a marine fish, the most widespread and abundant member of the smelt-whiting family Sillaginidae. The northern whiting was the first species of sillaginid scientifically described and is therefore the type species of both the family Sillaginidae and the genus Sillago. The species is distributed in the Indo-Pacific region from South Africa in the west to Japan and Indonesia in the east. The northern whiting inhabits coastal areas to 60 m, but is most often found in shallow water around bays and estuaries, often entering freshwater. It is a carnivore, taking a variety of polychaetes and crustaceans. The species is of major economic importance throughout the Indo-Pacific. It is most frequently taken by seine nets and cast nets and marketed fresh.
The greater amberjack, also known as the allied kingfish, great amberfish, greater yellowtail, jenny lind, Sea donkey, purplish amberjack, reef donkey, rock salmon, sailors choice, yellowtail, and yellow trevally, is a species of predatory ray-finned fish in the family Carangidae, the jacks and pompanos. It is found in temperate, subtropical, and tropical seas around the world. It is a popular quarry species for recreational fisheries and is important in commercial fisheries. It is the largest species in the family Carangidae.
The European anchovy is a forage fish somewhat related to the herring. It is a type of anchovy; anchovies are placed in the family Engraulidae. It lives off the coasts of Europe and Africa, including in the Mediterranean Sea, the Black Sea, and the Sea of Azov. It is fished by humans throughout much of its range.
Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, to spawn refers to the process of freely releasing eggs and sperm into a body of water ; the physical act is known as spawning. The vast majority of aquatic and amphibious animals reproduce through spawning. These include the following groups:
The round sardinella is a species of ray-finned fish in the genus Sardinella found in both sides of the Atlantic Ocean and the Mediterranean Sea.
Sardinella brasiliensis, is a species of ray-finned fish in the genus Sardinella. S. brasilensis are extremely hard to distinguish from Sardinella aurita and are combined in most studies and catch estimates. They spawn in coastal areas during late spring and summer. The most dense spawning periods are in December and January. From 1973 to 1990 the catch in Venezuela was down from 228000 tons to 31000 tons. These fish are present in the Western Atlantic (including the Gulf of Mexico, Caribbean, West Indies all the way down to Brazil
Sardinella zunasi is a species of ray-finned fish in the family Clupeidae, the herrings and sardines. It is native to the northwestern Pacific Ocean, where it occurs near shore along the Asian coastlines from southern Japan to Taiwan.
The European pilchard is a species of ray-finned fish in the monotypic genus Sardina. The young of the species are among the many fish that are sometimes called sardines. This common species is found in the northeast Atlantic, the Mediterranean, and the Black Sea at depths of 10–100 m (33–328 ft). It reaches up to 27.5 cm (10.8 in) in length and mostly feeds on planktonic crustaceans. This schooling species is a batch spawner where each female lays 50,000–60,000 eggs.
Ichthyoplankton are the eggs and larvae of fish. They are mostly found in the sunlit zone of the water column, less than 200 metres deep, which is sometimes called the epipelagic or photic zone. Ichthyoplankton are planktonic, meaning they cannot swim effectively under their own power, but must drift with the ocean currents. Fish eggs cannot swim at all, and are unambiguously planktonic. Early stage larvae swim poorly, but later stage larvae swim better and cease to be planktonic as they grow into juveniles. Fish larvae are part of the zooplankton that eat smaller plankton, while fish eggs carry their own food supply. Both eggs and larvae are themselves eaten by larger animals.
The Japanese jack mackerel, also known as the Japanese horse mackerel or Japanese scad, is a species named after its resemblance to mackerel but which is in the family Carangidae, the jacks, pompanos, trevallies and scads. Their maximum reported length is 50 cm (20 in) with a common length of 35 cm (14 in). They have a maximum reported weight of 0.66 kg (1.5 lb) and a maximum reported age of 12 years. They are found around the coast of Japan, except Okinawa Island, usually on sandy bottoms of 50–275 m (164–902 ft) deep. They feed mainly on small crustaceans such as copepods, as well as shrimp and small fish. They are similar to the yellowtail horse mackerel around New Zealand and Australia, apart from having more gill rakers and larger eyes.
Sardinella tawilis is a freshwater sardine found exclusively in the Philippines. It is the only member of the genus Sardinella known to exist entirely in fresh water. Locally, they are known in Filipino as tawilis.
Fish go through various life stages between fertilization and adulthood. The life of fish start as spawned eggs which hatch into immotile larvae. These larval hatchlings are not yet capable of feeding themselves and carry a yolk sac which provides stored nutrition. Before the yolk sac completely disappears, the young fish must mature enough to be able to forage independently. When they have developed to the point where they are capable of feeding by themselves, the fish are called fry. When, in addition, they have developed scales and working fins, the transition to a juvenile fish is complete and it is called a fingerling, so called as they are typically about the size of human fingers. The juvenile stage lasts until the fish is fully grown, sexually mature and interacting with other adult fish.