See text for species.
The Sillaginidae, commonly known as the smelt-whitings, whitings, sillaginids, sand borers and sand-smelts, are a family What does and does not belong to each family is determined by a taxonomist. Similarly for the question if a particular family should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing a family of benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean or a lake, including the sediment surface and some sub-surface layers. Organisms living in this zone are called benthos. They generally live in close relationship with the substrate bottom; many such organisms are permanently attached to the bottom coastal The coast is defined as where the land meets the sea. A precise line that can be called a coastline cannot be determined due to the dynamic nature of tides. The term "coastal zone" can be used instead, which is a spatial zone where interaction of the sea and land processes occurs. Both the terms coast and coastal are often used to marine Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology. As a noun it can be a term for a certain kind of navy, or those enlisted in such a navy fishes A fish is any aquatic vertebrate animal that is covered with scales, and equipped with two sets of paired fins and several unpaired fins. Most fish are "cold-blooded", or ectothermic, allowing their body temperatures to vary as ambient temperatures change. Fish are abundant in most bodies of water. They can be found in nearly all aquatic in the order The Latin suffix -formes meaning "having the form of" is used for the scientific name of orders of birds and fishes, but not for those of mammals and invertebrates Perciformes The Perciformes, also called the Percomorphi or Acanthopteri, is the largest order of vertebrates containing about 40% of all bony fish. Perciformes means perch-like. They belong to the ray-finned fish and comprise over 7000 species found in almost all aquatic environments. They are also the most variably sized order of vertebrates, ranging from. The smelt-whitings inhabit a wide region covering much of the Indo-Pacific The Indo-Pacific is a biogeographic region of the Earth's seas, comprising the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia. It does not include the temperate and polar regions of the Indian and Pacific oceans, and the Tropical Eastern Pacific, along, from the west coast of Africa Africa is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area. With a billion people (as of 2009, see table) in 61 territories, it accounts for about 14.72% of the world's human population east to Japan Japan is an island country in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south. The characters that make up Japan's name mean "sun-origin", which is why Japan is and south to Australia For at least 40,000 years before European settlement in the late 18th century, Australia was inhabited by indigenous Australians, who belonged to one or more of the roughly 250 language groups. After sporadic visits by fishermen from the immediate north and discovery by Dutch explorers in 1606, Australia's eastern half was claimed by the British. The family comprises only three genera In biology, a genus is a low-level taxonomic rank (a taxon) used in the classification of living and fossil organisms, which is an example of definition by genus and differentia. The term comes from Latin genus "descent, family, type, gender", cognate with Greek: γένος – genos, "race, stock, kin" and thirty one species In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are often used, such as based on similarity of DNA or, of which a number are dubious, with the last major revision of the family in 1992 unable to confirm the validity of a number of species. They are elongate, slightly compressed fish often light brown to silver in colour with a variety of markings and patterns on their upper body. The Sillaginidae are not related to a number of fishes commonly called 'whiting' in the Northern Hemisphere The Northern Hemisphere is the half of a planet that is north of equator—the word hemisphere literally means 'half sphere'. It is also that half of the celestial sphere north of the celestial equator. Earth's northern hemisphere contains most of its land area and most of its human population, including the fish originally called whiting, Merlangius merlangus Merlangius merlangus, commonly known as whiting is an important food fish in the eastern North Atlantic, northern Mediterranean, western Baltic, and Black Sea. In English speaking countries outside the whiting's natural range, the name has been applied to various other species of fish, see Whiting (fish) (disambiguation).
The smelt-whitings are mostly inshore fishes that inhabit sandy, silty and muddy substrates on both low and high energy environments ranging from protected tidal flats and estuaries An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea to surf zones. A few species predominantly live offshore on deep sand shoals A shoal, sandbar , or gravelbar is a somewhat linear landform within or extending into a body of water, typically composed of sand, silt or small pebbles. A spit or sandspit is a type of shoal. Shoals are characteristically long and narrow (linear) and develop where a stream or ocean current promotes deposition of granular material, resulting in and reefs In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water, although the larvae and juvenile phases of most species return to inshore grounds, where they spend the first few years of their lives. Smelt-whitings are benthic carnivores A carnivore , meaning 'meat eater' (Latin carne meaning 'flesh' and vorare meaning 'to devour'), is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging. Animals that depend solely on animal flesh for their nutrient requirements are that prey In ecology, predation describes a biological interaction where a predator feeds on its prey (the organism that is attacked). Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption. The other main predominantly on polychaetes The Polychaeta or polychaetes are a class of annelid worms, generally marine. Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin. Indeed, polychaetes are sometimes referred to as bristle worms. More than 10,000 species are described in this class. Common, a variety of crustaceans Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at 0.1 mm (0.004 in), to the Japanese spider crab with a leg span of up to 14 ft (4.3 m) and a mass, molluscs The Mollusca, common name molluscs or mollusks,[note 1] is a large phylum of invertebrate animals. There are around 85,000 recognized extant species of molluscs. This is the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats. Molluscs are highly diverse, and to a lesser extent echinoderms Echinoderms are a phylum of marine animals. Echinoderms are found at every ocean depth, from the intertidal zone to the abyssal zone. Aside from the problematic Arkarua, the first definitive members of the phylum appeared near the start of the Cambrian period and fish, feeding by detecting vibrations emitted by their prey.
The family is highly important to fisheries Generally, a fishery is an entity engaged in raising and/or harvesting fish, which is determined by some authority to be a fishery. According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats, purpose of the activities or a throughout the Indo-Pacific, with species such as the Northern whiting, Japanese whiting and King George whiting forming the basis of major fisheries throughout their range. Many species are also of major importance to small subsistence fisheries while others are little more than occasional bycatch The term bycatch is usually used for fish caught unintentionally in a fishery while intending to catch other fish. It may however also indicate untargeted catch in other forms of animal harvesting or collecting. Bycatch are either of a different species or juveniles of the target species. Smelt-whitings are caught by a number of methods including trawling Trawling is a method of fishing that involves pulling a large fishing net through the water behind one or more boats. The net that is used for trawling is called a trawl, seine nets Seine fishing is fishing using a seine. A seine is a large fishing net that hangs vertically in the water by attaching weights along the bottom edge and floats along the top. Boats equipped for seine fishing are called seiners and cast nets A cast net, also called a throw net, is a net used for fishing. It is a circular net with small weights distributed around its edge. In Australia and Japan in particular, members of the family are often highly sought by recreational fishermen Angling is a method of fishing by means of an "angle" . The hook is usually attached to a fishing line and the line is often attached to a fishing rod. Fishing rods are usually fitted with a fishing reel that functions as a mechanism for storing, retrieving and paying out the line. The hook itself can be dressed with lures or bait. A who also seek the fish for their prized flesh.
Contents |
Taxonomy
Roland McKay's 1992 Synopsis of the SillaginidaeThe first species of sillaginid to be scientifically described Biological classification, or scientific classification in biology, is a method by which biologists group and categorize organisms by biological type, such as genus or species. Biological classification is a form of scientific taxonomy, but should be distinguished from folk taxonomy, which lacks scientific basis. Modern biological classification was Sillago sihama, by Peter Forsskål in 1775, who initially referred the species to a genus of hardyhead, Atherina.[1] It was not until 1817 that the type genus Sillago was created by Georges Cuvier Georges Léopold Chrétien Frédéric Dagobert Cuvier was a French naturalist and zoologist. Of working class origins, he belonged to a new class of self-made scholars who worked their way to the top of academe. Cuvier was a major figure in natural sciences research in the early 19th century, and was instrumental in establishing the fields of based on his newly described species Sillago acuta, which was later found to be a junior synonym of S. sihama and subsequently discarded. Cuvier continued to describe species of sillaginid with the publishing of his ichthyological Ichthyology is the branch of zoology devoted to the study of fish. This includes skeletal fish (Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). While a majority of species have probably been discovered and described, approximately 250 new species are officially described by science each year. According to FishBase, 3 work Histoire Naturelle des Poissons with Achille Valenciennes in 1829, also erecting the genus Sillaginodes in this work.[1] The species Cheilodipterus panijus was named in 1822 by Francis Buchanan-Hamilton and was subsequently reexamined by Theodore Gill in 1861, leading to the creation of the monotypic In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and restoration ecology concerning a dominant invasive genus Sillaginopsis. John Richardson Sir John Richardson was a Scottish naval surgeon, naturalist and arctic explorer was the first to propose that Sillago, the only genus of sillaginid then recognised, be assigned to their own taxonomic family, "Sillaginidae" (used interchangeably with 'Sillaginoidae'), at a meeting of the British Association for the Advancement of Science The British Association for the Advancement of Science or the British Science Association, formerly known as the BA, is a learned society with the object of promoting science, directing general attention to scientific matters, and facilitating interaction between scientific workers. Membership is open to all.[2] There were, however, many differing opinions on the relationships of the "sillaginoids", leading to the naturalists of the day continually revising the position of the three genera, placing in them in a number of families. The first review of the sillaginid fishes was Gill's 1861 work "Synopsis of the sillaginoids", in which the name "Sillaginidae" was popularized and expanded on to include Sillaginodes and Sillaginopsis,[3] however the debate on the placement of the family remained controversial.[4]
In the years after Gill's paper was published, over thirty 'new' species of sillaginid were reported and scientifically described, many of which were synonyms Synonyms are different words with identical or very similar meanings. Words that are synonyms are said to be synonymous, and the state of being a synonym is called synonymy. The word comes from Ancient Greek syn ("with") and onoma (ὄνομα) ("name"). The words car and automobile are synonyms. Similarly, if we talk about a of previously described species, with similarity between species as well as minor geographical variation Genetic diversity, the level of biodiversity, refers to the total number of genetic characteristics in the genetic makeup of a species. It is distinguished from genetic variability, which describes the tendency of genetic characteristics to vary confounding taxonomists Taxonomy is the practice and science of classification. The word finds its roots in the Greek τάξις, taxis and νόμος, nomos (meaning 'law' or 'science'). Taxonomy uses taxonomic units, known as taxa (singular taxon).[5] It wasn't until 1985 when Roland McKay of the Queensland Museum published a comprehensive review of the family that these relationships were formally resolved, although a number of species are still listed as doubtful, with McKay unable to locate the holotypes. Along with the review of previously described species, McKay described an additional seven species, a number of which he described as subspecies Subspecies in biological classification, is either a taxonomic rank subordinate to species, or a taxonomic unit in that rank (plural: subspecies). A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one.[4] After this 1985 paper, additional specimens A laboratory specimen is an individual animal, part of an animal, plant, part of a plant, or microorganism used as a representative to study the properties of the whole population of that species or subspecies. When a taxon is described, it is typically based on a single specimen, then referred to as the holotype came to light, proving that all the subspecies he had identified were individual species. In 1992 McKay published a synopsis of the Sillaginidae for the FAO The Food and Agriculture Organization of the United Nations is a specialised agency of the United Nations that leads international efforts to defeat hunger. Serving both developed and developing countries, FAO acts as a neutral forum where all nations meet as equals to negotiate agreements and debate policy. FAO is also a source of knowledge and, in which he elevated these subspecies to full species status.[5]
The name "Sillaginidae" was derived from Cuvier's Sillago, which itself takes its name from a locality in Australia,[6] possibly Sillago reef off the coast of Queensland.[7] The term Sillago is derived from the Greek term "syllego", which means "to meet".[8]
Classification
The following is a comprehensive list of the 31 known extant Extant is a term commonly used in biology to refer to taxa that are still in existence (living). The term extant contrasts with extinct. For example, Brandt's Cormorant is an extant species, while the Spectacled Cormorant is an extinct species. Likewise, of the group of molluscs known as the cephalopods, there are approximately 600 extant species species of sillaginids, with a number of the species still in doubt due to the loss of the holotype specimen. This classification follows Fishbase FishBase is a comprehensive database of information about fish. As of October 2008[update], it included descriptions of over 30,000 species, over 260,000 common names in hundreds of languages, over 46,000 pictures, and references to more than 42,000 works in the scientific literature, which itself is based on McKay's last revision of the family.[8]
Oriental trumpeter whiting, Sillago aeolus Southern school whiting, Sillago bassensis Sand whiting The sand whiting, Sillago ciliata, is a common species of coastal marine fish of the family Sillaginidae, the smelt-whitings. It is a slender, slightly compressed fish that is very similar to other species of Sillago, with detailed spine, ray and lateral line scale counts needed to distinguish the species between its nearest relative Sillago, Sillago ciliata Club-foot whiting, Sillago chondropus Bay whiting, Sillago ingenuua- Family SILLAGINIDAE
- Genus Sillaginodes
- King George whiting, Sillaginodes punctatus (Cuvier, 1829).
- Genus Sillaginopsis
- Gangetic whiting, Sillaginopsis panijus (Hamilton, 1822).
- Genus Sillago
- Oriental trumpeter whiting, Sillago aeolus (Jordan David Starr Jordan, Ph.D., LL.D. was a leading eugenicist, ichthyologist, educator and peace activist. He was president of Indiana University and Stanford University & Evermann, 1902)
- Golden lined whiting, Sillago analis (Whitley, 1943)
- Shortnose whiting, Sillago arabica (McKay & McCarthy, 1989)
- Silver-banded whiting, Sillago argentifasciata (Martin & Montalban, 1935)
- Asian whiting, Sillago asiatica (McKay, 1982)
- Slender whiting, Sillago attenuata (McKay, 1985)
- Southern school whiting, Sillago bassensis (Cuvier, 1829)
- Boutan's whiting, Sillago boutani (Pellegrin, 1905)
- Western trumpeter whiting, Sillago burrus (Richardson, 1842)
- Club-foot whiting, Sillago chondropus (Bleeker, 1849)
- Sand whiting The sand whiting, Sillago ciliata, is a common species of coastal marine fish of the family Sillaginidae, the smelt-whitings. It is a slender, slightly compressed fish that is very similar to other species of Sillago, with detailed spine, ray and lateral line scale counts needed to distinguish the species between its nearest relative Sillago, Sillago ciliata (Cuvier, 1829)
- Eastern school whiting, Sillago flindersi (McKay, 1985)
- Indian whiting, Sillago indica (McKay, Dutt & Sujatha, 1985)
- Bay whiting, Sillago ingenuua (McKay, 1985)
- Thai whiting, Sillago intermedius (Wongratana, 1977)
- Japanese whiting, Sillago japonica (Temminck & Schlegel, 1843)
- Mud whiting, Sillago lutea (McKay, 1985)
- Large-scale whiting, Sillago macrolepis (Bleeker, 1859)
- Trumpeter whiting, Sillago maculata (Quoy and Gaimard, 1824)
- Large-headed whiting, Sillago megacephalus (Lin, 1933)
- Small-eyed whiting, Sillago microps (McKay, 1985)
- Rough whiting, Sillago nierstraszi (Hardenberg, 1941)
- Small-scale whiting, Sillago parvisquamis (Gill, 1861)
- Stout whiting, Sillago robusta (Stead, 1908)
- Yellowfin whiting, Sillago schomburgkii (Peters, 1864)
- Northern whiting, Sillago sihama (Forsskål, 1775)
- Soringa whiting, Sillago soringa (Dutt and Sujatha, 1982)
- Estuarine whiting, Sillago vincenti (McKay, 1980)
- Western school whiting, Sillago vittata (McKay, 1985)
- Genus Sillaginodes
Evolution
A number of sillaginids have been identified from the fossil record Fossils are the preserved remains or traces of animals, plants, and other organisms from the remote past. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous (fossil-containing) rock formations and sedimentary layers (strata) is known as the fossil record. The study of fossils across geological time, how, with the lower Eocene The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Palaeogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by the emergence of the first marking the first appearance of the family. The family is thought to have evolved Evolution is the change in the inherited traits of a population of organisms through successive generations. After a population splits into smaller groups, these groups evolve independently and may eventually diversify into new species. Ultimately, life is descended from a common ancestory through a long series of these speciation events, in the Tethys Sea of central Australia, before colonizing southern Australia during the upper Eocene after a seaway broke through south of Tasmania.[5] During the Oligocene, the family spread to the north and south, occupying a much more extensive range than their current Indo-Pacific distribution. Fossils suggest the sillaginids ranged as far north as Poland and Germany, and as far south as New Zealand,[9] found in shallow water sedimentary deposits along with other species of extant genera.[10]
There have been at least eight fossil sillaginid species found, all of which are believed to be of the genus Sillago based on the only remains found; otoliths. Only one species of extant sillaginid, Sillago maculata, has been found in the fossil record, and this was in very recent Pleistocene sediments.[11]
- Sillago campbellensis (Schwarzhans, 1985) Australia, Miocene[12]
- Sillago hassovicus (Koken, 1891) Poland, Middle Miocene[10]
- Sillago maculata (Quoy and Gaimard, 1824) New Zealand, Middle Pleistocene[11]
- Sillago mckayi (Schwarzhans, 1985) Australia, Oligocene[12]
- Sillago pliocaenica (Stinton, 1952) Australia, Pliocene[13]
- Sillago recta (Schwarzhans, 1980) New Zealand, Upper Miocene[9]
- Sillago schwarzhansi (Steurbaut, 1984) France, Lower Miocene[14]
- Sillago ventriosus (Steurbaut, 1984) France, Upper Oligocene[14]
Phylogeny
|
The relationships of the Sillaginidae are poorly known, with very similar morphological characteristics and a lack of genetic studies restricting the ability to perform cladistic analyses on the family. Being the fossil sillaginids are based on the comparison of fossil otoliths, with no other type of remains found thus far, this also prevents the reconstruction of the evolution of the family through fossil species. While the position of the Sillaginidae in the order Perciformes is firmly established due to a number of synapomorphies shared with other members of the order, no sister group has been established for the family.[15] The current taxonomic status of the family is thought to represent a basic picture of the group's phylogeny, with McKay further dividing the genus Sillago into three subgenera based on shared morphological characters of the swimbladder. The genera Sillaginodes and Sillaginopsis have the most plesiomorphic characteristics; being monotypic, and distinct from Sillago. Sillago is further divided into three subgenera based primarily on swim bladder morphology; Sillago, Parasillago and Sillaginopodys, which also represent evolutionary relationships.[5] Whilst genetic studies have not been done on the family, they have been used to establish the relationship of what were thought to be various subspecies of school whiting, S. bassensis and S. flindersi.[16] Furthermore, morphological data suggests a number of Australian species diverged very recently during the last glacial maximum, which caused land bridges to isolate populations of fish. The two aforementioned species of school whiting, S. maculata and S. burrus, and S. ciliata and S. analis are all thought to be products of such a process, although only the school whiting have anything other than similar morphology as evidence of this process.[4]
Morphology
The Sillaginidae are medium sized fishes which grow to an average of around 20 cm and around 100 g,[17] although the largest member of the family, the King George whiting is known to reach 72 cm and 4.8 kg in weight. The body shape and fin placement of the family is quite similar to most of the members of the order Perciformes.[18] Their bodies are elongate, slightly compressed, with a head that tapers toward a terminal mouth. The mouth has a band of brush-like teeth with canine teeth present only in the upper jaw of Sillaginopsis. The cranial sensory system of the family is well developed above and laterally, with the lower jaw having a pair of small pores behind which is a median pit containing a pore on each side. On each side of the elongate head the operculum has a short sharp spine. They have two true dorsal fins; the anterior one supported by 10 to 13 spines while the long rear one is held up by a single leading spine followed by 16 to 27 soft rays. The anal fin is similar to the second dorsal fin, having two small slender spines followed by 14 to 26 soft rays.[18] Their bodies are covered in ctenoid scales, with the exception of the cheek which may have cycloid or ctenoid scales. There is a wide variation in the amount of lateral line scales, ranging from 50 to 141.[15] The swimbladder in the Sillaginidae is either absent, poorly developed, or highly complex with anterior and lateral extensions that project well into the caudal region. A unique duct-like process is present from the ventral surface of the swimbladder to just before the urogenital opening in most species. The presence and morphology of each species' swim bladder is often their major diagnostic feature, with McKay's three proposed subgenera based on swimbladder morphology alone.[4] The sillaginids have only a small range of body colourings and frequently the only colour characteristics to identify between species are the arrangements of spots and bars on their upper bodies. Most of the family are a pale brown – creamy white colour, while a few species are silver all over. The undersides of the fish are usually lighter than the upper side, and the fins range from yellow to transparent, often marked by bars and spots.[4]
Distribution and habitat
The current geographical distribution of the family SillaginidaeThe Sillaginidae are distributed throughout the Indo-Pacific region, ranging from the west coast of Africa to Japan and Taiwan in the east, as well occupying as a number of small islands including New Caledonia in the Pacific Ocean.[15] While they have a fairly wide distribution, the highest species densities occur along the coasts of India, China, Taiwan, South East Asia, the Indonesian Archipelago and northern Australia.[5] One species of sillaginid, Sillago sihama, has been declared an invasive species to the Mediterranean, passing through the Suez Canal from the Red Sea since 1977 as part of the Lessepsian migration, becoming widespread.[19]
Sillaginids are primarily inshore marine fishes inhabiting stretches of coastal waters, although a few species move offshore in their adult stages to deep sand banks or reefs to a maximum known depth of 180 m.[20] All species primarily occupy sandy, silty or muddy substrates, often using seagrass or reef as cover. They commonly inhabit tidal flats, beach zones, broken bottoms and large areas of uniform substrate. Although the family is marine, many species inhabit estuarine environments, with some such as Sillaginopsis panijus also found in the upper reaches of the estuary.[21] Each species often occupies a specific niche to avoid competition with co-occurring sillaginids, often inhabiting a specific substrate type, depth, or making use of surf zones and estuaries.[22] The juveniles often show distinct changes in habitat preference as they mature, often moving to deeper waters.[20] No members of the family are known to undergo migratory movements, and have been shown to be relatively weak swimmers, relying on currents to disperse juveniles.
Biology
Diet and feeding
The smelt-whitings are benthic carnivores, with all of the species whose diets have been studied showing similar prey preferences. Studies from the waters of Thailand, Philippines and Australia have shown that polychaetes, a variety of crustaceans, molluscs and to a lesser extent echinoderms and fish are the predominant prey items of the family.[23][24][25] Commonly taken crustaceans include decapods, copepods and isopods, while the predominant molluscs taken are various species of bivalves, especially the unprotected siphon filters that protrude from the shells. In all species studied, some form of diet shift occurs as the fishes mature, often associated with a movement to deeper waters and thus to new potential prey. The juveniles often prey on planktonic prey, with small copepods, isopods and other small crustaceans often taken.[26] Whilst many species have a change in niche to reduce intraspecific competition, there are often many species of sillaginid inhabiting a geographical area. Where this occurs, there is often definite diet differences between species, often associated with a niche specialization.[25] The sillaginid's distinctive body shape and mouth placement is an adaptation to bottom feeding, which is the predominant method of feeding for all whiting species. All larger whiting feed by using their protrusile jaws and tube-like mouths to suck up various types of prey from in, on or above the ocean substrate,[22] as well as using their nose as a 'plough' to dig through the substrate.[5] There is a large body of evidence that shows whiting do not rely on visual cues when feeding, instead using a system based on the vibrations emitted by their prey.[27]
Predators
Smelt-whitings are a major link in the food chain of most systems, and frequently fall prey to a variety of aquatic and aerial predators. Their main aquatic predators are a wide variety of larger fish, including both teleosts and a variety of sharks and rays.[28] Marine mammals including seals[29] and dolphins[30] have been reported to have taken sillaginids as a main food source. Seabirds are also another major predator of the family, with diving species such as Cormorants taking older fish in deeper waters while juvenile fish in shallow water fall prey to wading birds.[31] Sillaginids are often called 'sandborers' due to their habit of burying themselves in the substrate to avoid predators, much in the same way as they forage, by ploughing their nose into the substrate. This defense is even used against human fishermen, who frequently wade barefoot to feel for buried fish.[5] The Sillaginidae are also host to a variety of well studied internal and external parasites, which are represented prominently by the groups Digenea, Monogenea and Myxosporea , Copepoda and Nematoda.[32][33]
Reproduction
The Sillaginidae are an oviparous, non guarding family,[8] whose species tend to show similar reproductive patterns to one another. Each species reaches sexual maturity at a slightly different age, with each sex often showing a disparity in time of maturation.[20][34] Each species also spawns over a different season and the spawning season often differs within a species, usually as a function of latitude; a feature not unique to sillaginids.[35] The proximity to shore of spawning is also different between species, as each species usually does not migrate inshore to spawn, even if the juveniles require shallow water for protection, instead relying on currents.[36] The fecundity of sillaginids is variable, with a normal range between 50 000 – 100 000. The eggs are small (0.6 to 0.8 mm), spherical and pelagic, hatching around 20 days after fertilisation.[37] The larvae are quite similar, requiring a trained developmental biologist to identify between species.[38] The larvae and juveniles are at the mercy of the ocean currents, being too weaker swimmers to actively seek out coastlines. Currents are thought to have been responsible for the distribution of mainland species to offshore islands as well as the current widespread distribution of Sillago sihama.[32] In all studied species, juveniles inhabit shallow waters in protected embayments, estuaries, tidal creeks and lagoons as well as exposed surf zones, usually over tidal flats and seagrass beds. As the fish mature, they generally move to deeper waters, showing a change in diet.[25]
Relationship to humans
The sillaginids are some of the most important commercial fishes in the Indo-Pacific region, with a few species making up the bulk of whiting catches. Their high numbers, coupled with their highly regarded flesh are the reason for this, and their inshore nature also has made them popular targets for recreational fishermen in a number of countries.[5] With overfishing rife in some areas, sustainable aquaculture has allowed the commercial farming of a number of sillaginid species, as well as the use of farmed fish to restock depleted estuaries. At least one species, the Gangetic whiting, has occasionally been used in brackish water aquaria.[39]
Commercial fisheries
A species of sillaginid for sale as "asuhos" in the PhilippinesA small number of sillaginids have large enough populations to allow an entire fishery to be based around them, with King George whiting,[18] northern whiting, Japanese whiting,[40] sand whiting and school whiting the major species. There have been no reliable estimates of catches for the entire family, as catch statistics generally include only those species taken in large numbers, but there are some species which make up significant numbers of the bycatch. To add to this problem, many of the lesser known species are taken by subsistence fisheries and not reported. From estimates by the FAO, however, it is evident that the family is one of the most important in the Indo-Pacific region, having an estimated catch of 22 718 tonnes in 1990 alone.[5] In this same report, it was shown that the greatest three utilizers of sillaginids were the Philippines, Western Australia and Thailand respectively. The records also suggested that the catch increased from 1983 when it was 17 570 t, up to the last estimate in 1990 of 22 718 t. No such estimates have been carried out since. Modern records for Australia show that this trend has reversed, with all catches from Australia totaling 4 372 t in 2006 compared with 1990's 6000 t haul.[41] Statistics from other countries are unavailable for such comparison.
Sillaginids are taken by a variety of fishing methods, with inshore catches predominantly taken using beach seine nets and cast nets. Due to the alert nature of sillaginids, skill is required on creeping up quietly enough to be able to net fish with a cast net, with experienced fishers often paddling into the sun toward a school and drifting slowly upon it before casting the net.[5] In deeper waters, commercial trawlers and longliners take the most fish, with a number of sillaginids taken in prawn trawls as bycatch. The fish are normally marketed fresh locally under various names, with "Ashuos" commonly used in many countries for various sillaginids.[8] At least one export fishery exists in Australia whereby S. flindersi is exported to Thailand where the fish are repackaged and sent to Japan frozen.[42]
Recreational fisheries
Main article: Smelt-whiting fishingIn Australia and Japan, members of the family are highly sought after by anglers for their sporting and eating qualities, with anglers often taking more than commercial fishermen in some areas.[43] The fishing techniques for all sillaginids are quite similar, with the shallow habitats often requiring light line and quiet movements. Whiting are also popular in part due to their accessibility, with tidal flats around beaches, estuaries and jetties common habitats from where many whiting species are caught without need for a boat.[44] Tidal movements also affect catches, as do lunar phases, causing whiting to 'bite' when the tide is changing. Tackle used is kept light to avoid spooking the fish, and often requires only a simple setup, with a hook and light sinker tied directly to the mainline usually effective. In deeper water fished from boats or where currents are strong, more complex rigs are used, often with hooks tied to dropper loops on the trace.[44] in Australia, some specialist whiting fishermen who target the fish in the surf or on shallow banks use red beads or tubing to attract the fish, claiming the method produces more fish.[45] The bait used is normally anything from the surrounding environment which the whiting naturally prey on, with polychaetes, bivalves, crustaceans such as prawns and crabs, cephalopods and small fish effective for most species. As with most species, live bait is known to produce better catches. Lure fishing for whiting is not normally practiced, but saltwater flies have been used to good effect, as have small soft plastic lures.[45] In some areas, restrictions to the amount and size of fish are in place and enforced by fishery authorities.[46]
Aquaculture
A number of sillaginid species have been the subject of brackish water aquaculture in Asia and India,[5] with species including S. japonica commonly bred for consumption. In Australia, research has been undertaken in the breeding of sand whiting and King George whiting, and so far only sand whiting shows promise for commercial viability.[47] King George whiting have been found to take too long to develop to be sustainable, but the use of growth hormones is being investigated.[48] In Australia, aquaculturally bred sand whiting have also been used to stock depleted estuaries.
References
- ^ a b Hosese, D.F.; Bray, D.J., Paxton, J.R. and Alen, G.R. (2007). Zoological Catalogue of Australia Vol. 35 (2) Fishes. Sydney: CSIRO. p. 1126. ISBN 978-0-643-09334-8.
- ^ Richardson, John (1846). "Report on the ichthyology of the seas of China and Japan". Report of the British Association for the Advancement of Science 15: 187–320.
- ^ Gill, Theodore N. (1861). "Synopsis of the Sillaginoids". Proceedings of the Academy of Natural Sciences of Philadelphia 13: 501–505.
- ^ a b c d e f McKay, R.J. (1985). "A Revision of the Fishes of the Family Sillaginidae". Memoirs of the Queensland Museum 22 (1): 1–73.
- ^ a b c d e f g h i j k McKay, R.J. (1992). FAO Species Catalogue: Vol. 14. Sillaginid Fishes Of The World. Rome: Food and Agricultural Organisation. pp. 19–20. ISBN 92-5-103123-1. ftp://ftp.fao.org/docrep/fao/009/t0538e/t0538e06.pdf.
- ^ Froese, Rainer, and Daniel Pauly, eds. (2007). Species of Sillago in FishBase. September 2007 version.
- ^ Great Barrier Reef Marine Park Authority (2006-01-09). "Whitsunday Plan of Management Area" (pdf). Australian Government. http://www.gbrmpa.gov.au/__data/assets/pdf_file/0005/1688/pipi_map_whit.pdf. Retrieved 2007-09-01.
- ^ a b c d Froese, Rainer, and Daniel Pauly, eds. (2007). "Sillaginidae" in FishBase. September 2007 version.
- ^ a b Schwarzhans, Werner W (1980). "Die Tertiare Teleosteer-Fauna Neuseelands, rekonstruiert anhand von Otolithen". Berliner Geowissenschaftliche Abhandlungen Reihe a Geologie und Palaeontologie 26: 1–211. ISSN 0172-8784.
- ^ a b Smigielska, T. (1979). "Fish otoliths from the Korytnica Clays (Middle Miocene; Holy Cross Mountains, central Poland)". Acta Geologica Polonica 29 (3): 295–337. ISSN 0001-5709.
- ^ a b Grenfell, Hugh R.; Werner W. Schwarzhans (1999). "The fish otolith fauna of the Te Piki Member". Proceedings of the Taupaki Malacological Society 2: 12–14. ISSN 1174-2348.
- ^ a b Schwarzhans, werner W. (1985). "Tertiare Otolithen aus South Australia und Victoria (Australien)". Palaeo Ichthyologica 3: 1–60. ISSN 0724-6331.
- ^ Stinton, F.C. (1958). "Fish otoliths from the tertiary strata of Victoria, Australia". Proceedings of the Royal Society of Victoria 70 (1): 81–93.
- ^ a b Steurbaut, E. (1984). "Les otolithes de Teleosteens de l'oligo-miocene d'Aquitaine (sud ouest de la France)". Palaeontographica Abteilung a Palaeozoologie-Stratigraphie 186 (1-6): 1–162. ISSN 0375-0442.
- ^ a b c Nelson, Joseph S. (2006). Fishes of the World. John Wiley & Sons, Inc. pp. 278–280. ISBN 0-471-25031-7.
- ^ Dixon, P.I., R.H. Crozier, M. Black and A. Church. (1987) Stock identification and discrimination of commercially important whitings in Australian waters using genetic criteria (FIRTA 83/16). Centre for Marine Science, University of New South Wales. 69 p. Appendices 1-10.
- ^ Kuiter, R.H. (1993). Coastal fishes of south-eastern Australia. U.S.A: University of Hawaii Press. ISBN 1 86333 067 4.
- ^ a b c Scott, T.D.; C.J.M. Glover & R.V. Southcott (1980). Marine and Freshwater Fishes of South Australia 2nd Edition. Adelaide: Government Printer.
- ^ Golani, Daniel (1998). "Impact of Red Sea Fish Migrants through the Suez Canal on the Aquatic Environment of the Eastern Mediterranean" (). Yale School of Forestry and Environmental Studies Bulletin 103 (Transformations of Middle Eastern Natural Environments): 375–387. http://environment.yale.edu/documents/downloads/0-9/103golani.pdf. Retrieved 2007-10-14.
- ^ a b c Hyndes, G.A.; I. C. Potter & S. A. Hesp (September 1996). "Relationships between the movements, growth, age structures, and reproductive biology of the teleosts Sillago burrus and S. vittata in temperate marine waters". Marine Biology 126 (3): 549–558. doi:10.1007/BF00354637.
- ^ Krishnayya, C.G. (1963). "On the use of otoliths in the determination of age and growth of the Gangetic whiting, Sillago panijus (Ham.Buch.), with notes on its fishery in Hooghly estuary". Indian Joural of Fisheries 10: 391–412.
- ^ a b Hyndes, G.A.; M. E. Platell, I. C. Potter (1997). "Relationships between diet and body size, mouth morphology, habitat and movements of six sillaginid species in coastal waters: implications for resource partitioning". Marine Biology 128 (4): 585–598. doi:10.1007/s002270050125.
- ^ Tongnunui, P.; Sano, M. & Kurokura, H. (2005). "Feeding habits of two sillaginid fishes, Sillago sihama and S-aeolus, at Sikao Bay, Trang Province, Thailand". Mer (Tokyo) 43 (1/2): 9–17. ISSN:0503-1540. http://sciencelinks.jp/j-east/article/200601/000020060105A1017511.php. Retrieved 2007-10-15.
- ^ Mitsuhiro, Kato; Hiroshi Kohno & Yasuhiko Taki (November 1996). "Juveniles of two sillaginids,Sillago aeolus andS. sihama, occurring in a surf zone in the Philippines". Ichthyological Research (Springer Japan) 43 (4): 1341–8998. doi:10.1007/BF02347640.
- ^ a b c Hyndes, G.A.; M. E. Platell & I. C. Potter (June 1997). "Relationships between diet and body size, mouth morphology, habitat and movements of six sillaginid species in coastal waters: implications for resource partitioning". Marine Biology (Springer Berlin / Heidelberg) 128 (4): 585–598. doi:10.1007/s002270050125.
- ^ Coull, Bruce C.; Jack G. Greenwood, Donald R. Fielder & Brent A. Coull (1995). "Subtropical Australian juvenile fish eat meiofauna: experiments with winter whiting Sillago maculata and observations on other species". Marine Ecology Progress Series 125: 13–19. doi:10.3354/meps125013. ISSN 0171-8630.
- ^ Hadwen, W.L.; Russell, G.L.; Arthington, A.H. (1985). "The food, feeding habits and feeding structures of the whiting species Sillago sihama (ForsskaÊ l) and Sillago analis Whitley from Townsville, North Queensland, Australia.". Journal of Fish Biology 26: 411–427. doi:10.1111/j.1095-8649.1985.tb04281.x. http://www.blackwell-synergy.com/doi/abs/10.1111/j.1095-8649.1985.tb04281.x.
- ^ Froese, Rainer, and Daniel Pauly, eds. (2007). "Sillaginodes punctatus" in FishBase. Oct 2007 version.
- ^ Page, Brad; Jane McKenzie & Simon D. Goldsworthy (June, 2005). "Dietary resource partitioning among sympatric New Zealand and Australian fur seals". Marine Ecology Progress Series 293: 283–302. doi:10.3354/meps293283.
- ^ Long, M.; Rob J. Reid (1997). "Cadmium accumulation and toxicity in the bottlenose dolphin Tursiops truncatus, the common dolphin Delphinus delphis, and some dolphin prey species in South Australia". Australian Mammalogy 20 (1): 25–33. ISSN 0310-0049.
- ^ Humphries, P.; Hyndes, G.A & Potter, I.C. (1992). "Comparisons between the diets of distant taxa (Teleost and Cormorant) in an Australian estuary". Estuaries 15 (3): 327–334. doi:10.2307/1352780. ISSN 0160-8347. http://jstor.org/stable/1352780. Retrieved 2007-10-17.
- ^ a b Hayward, Craig J. (1997). "Distribution of external parasites indicates boundaries to dispersal of sillaginid fishes in the Indo-West Pacific". Marine and Freshwater Research (CSIRO) 48 (5): 391–400. doi:10.1071/MF96125.
- ^ Gibson, D.I. (1987). "Two new lepocreadiids (Digenea) from Sillago spp. (Pisces: Sillaginidae) in Australian waters". Journal of Natural History (Taylor & Francis) 21 (1): 159–166. doi:10.1080/00222938700770041. ISSN 0022-2933.
- ^ Coulson, Peter G.; S. Alex Hesp, Ian C. Potter & Norman G. Hall (2005). "Comparisons between the biology of two co-occurring species of whiting (Sillaginidae) in a large marine embayment". Environmental Biology of Fishes (Springer Netherlands) 73 (2): 125–139. doi:10.1007/s10641-004-4568-8.
- ^ Sheaves, Marcus (2006). "Is the timing of spawning in sparid fishes a response to sea temperature regimes?". Coral Reefs (Springer Berlin / Heidelberg) 25 (4): 655–669. doi:10.1007/s00338-006-0150-5.
- ^ Jenkins, G.P.; D.C. Welsford (2002). "The swimming abilities of recently settled post-larvae of Sillaginodes punctata". Journal of Fish Biology (Blackwell Synergy) 60 (4): 1043–1050. doi:10.1111/j.1095-8649.2002.tb02427.x.
- ^ Leis, J.M.; T. Trnski (1989). The Larvae of Indo-Pacific Shorefishes. Kensington: New South Wales University Press. p. 372 p. ISBN 978-0824812652.
- ^ Bruce, B.D. (1995). "Larval development of King George whiting, Sillaginodes punctata, school whiting, Sillago bassensis, and yellow fin whiting, Sillago schomburgkii (Percoidei: Sillaginidae), from South Australian waters". US National Marine Fisheries Service Fishery Bulletin (Elsevier Science) 93 (1): 27–43.
- ^ Schaefer, Frank (2005). Brackish-water fishes : all about species, care and breeding. Rodgau: Aqualog. ISBN 3-936027-82-X.
- ^ Purbayanto, Ari; Seiji Akiyama, Tadashi Tokai and Takafumi Arimoto (February 2000). "Mesh selectivity of a sweeping trammel net for Japanese whiting Sillago japonica". Fisheries Science (Blackwell Synergy) 66 (1): 97–103. doi:10.1046/j.1444-2906.2000.00014.x. http://www.blackwell-synergy.com/doi/abs/10.1046/j.1444-2906.2000.00014.x?cookieSet=1&journalCode=fis. Retrieved 2007-01-27.
- ^ Australian Bureau of Agricultural and Resource Economics (June, 2007). Australian Fisheries Statistics 2006. Canberra: ABARE. p. 28. ISSN 1037-6879. http://www.abareconomics.com/publications_html/fisheries/fisheries_07/07_fishstats.pdf.
- ^ Kailola, P.J.; M.J Williams, R.E. Stewart (1993). Australian fisheries resources. Canberra: Bureau of Resource Sciences. ISBN 0-642-18876-9.
- ^ Wilkinson, J. (2004). NSW Fishing Industry: Changes and Challenges in the Twenty-First Century. Sydney: NSW Parliamentary Library Research Service. pp. 174–178. ISBN 0 7313 1768 8. http://www.parliament.nsw.gov.au/prod/parlment/publications.nsf/0/07532F82AC6487FFCA256F16001BBE85.
- ^ a b Starling, S. (1988). The Australian Fishing Book. Hong Kong: Bacragas Pty. Ltd.. p. 490. ISBN 073010141x.
- ^ a b Horrobin, P. (1997). Guide to Favourite Australian Fish. Singapore: Universal Magazines. pp. 102–103.
- ^ Department of Primary Industries (2007). "Recreational Fishing Guide" (pdf). Limits and Closed Seasons. Government of Victoria. http://www.dpi.vic.gov.au/dpi/nrenfaq.nsf/LinkView/038067B67D8D0260CA2571F6007C592FB43DB2A1BECEB2A04A256812001DD817#bag. Retrieved 2007-10-10.
- ^ Burke, Michael. "Marine fingerling production at the Bribie Island Aquaculture Research Centre intensive green-water culture: An historical perspective". http://www.aims.gov.au/pages/research/hatchery-feeds/pdf/chapter04.pdf.
- ^ Partridge, G. (2000). Further development of techniques for the culture of King George whiting for commercial aquaculture or for enhancement of fish stocks in Western Australia - Final Report. Fremantle: Challenger TAFE.
External links
| Wikimedia Commons has media related to: Sillaginidae |
| Wikispecies has information related to: Sillaginidae |
|
|||||||||||||||||||||||||||||||||||||
Categories: Sillaginidae | Fish of the Pacific Ocean | Commercial fish
|