78-553: The Pacific reef heron ( Egretta sacra ), also known as the eastern reef heron or eastern reef egret , is a species of heron found throughout southern Asia and Oceania . It occurs in two colour morphs with either slaty grey or pure white plumage. The sexes are similar in appearance. The Pacific reef heron was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus 's Systema Naturae . He placed it with
156-1054: A dagger (†); groups of uncertain placement are labelled with a question mark (?) and dashed lines (- - - - -). Jawless fishes (118 species: hagfish , lampreys ) [REDACTED] † Thelodonti , † Conodonta , † Anaspida [REDACTED] [REDACTED] [REDACTED] † Galeaspida [REDACTED] † Osteostraci [REDACTED] † Placodermi [REDACTED] † Acanthodii [REDACTED] (>1,100 species: sharks , rays , chimaeras ) [REDACTED] (2 species: coelacanths ) [REDACTED] Dipnoi (6 species: lungfish ) [REDACTED] Tetrapoda (>38,000 species, not considered fish: amphibians, reptiles, birds, mammals) [REDACTED] (14 species: bichirs , reedfish ) [REDACTED] (27 species: sturgeons , paddlefish ) [REDACTED] Ginglymodi (7 species: gars , alligator gars ) [REDACTED] Halecomorphi (2 species: bowfin , eyetail bowfin ) [REDACTED] (>32,000 species) [REDACTED] Fishes (without tetrapods) are
234-579: A paraphyletic group and for this reason, the class Pisces seen in older reference works is no longer used in formal classifications. Traditional classification divides fish into three extant classes (Agnatha, Chondrichthyes, and Osteichthyes), and with extinct forms sometimes classified within those groups, sometimes as their own classes. Fish account for more than half of vertebrate species. As of 2016, there are over 32,000 described species of bony fish, over 1,100 species of cartilaginous fish, and over 100 hagfish and lampreys. A third of these fall within
312-574: A "siege". The word heron first appeared in the English language around 1300, originating from Old French hairon, eron (12th century), earlier hairo (11th century), from Frankish haigiro or from Proto-Germanic *haigrô , *hraigrô . Herons are also known as shitepokes / ˈ ʃ aɪ t p oʊ k / , or euphemistically as shikepokes or shypokes . Webster's Dictionary suggests that herons were given this name because of their habit of defecating when flushed. The 1971 Compact Edition of
390-866: A greenish to yellow cast. The Pacific reef heron is widely distributed across southern Asia and Oceania. In Australia , Pacific reef herons inhabits most of the coastline, and offshore islands including the Torres Strait Islands . Pacific reef herons are widespread across Micronesia , with breeding records in Guam , the Marshall Islands , Northern Mariana Islands , and Palau , among various other islands. The species also breeds throughout western Polynesia , including in Fiji , French Polynesia , and Tonga – though it does not breed in Niue . Surveys of
468-436: A more spherical lens . Their retinas generally have both rods and cones (for scotopic and photopic vision ); many species have colour vision , often with three types of cone. Teleosts can see polarized light ; some such as cyprinids have a fourth type of cone that detects ultraviolet . Amongst jawless fish , the lamprey has well-developed eyes, while the hagfish has only primitive eyespots. Hearing too
546-414: A part of a larger cycle of life and death. Fish A fish ( pl. : fish or fishes ) is an aquatic , anamniotic , gill -bearing vertebrate animal with swimming fins and a hard skull , but lacking limbs with digits . Fish can be grouped into the more basal jawless fish and the more common jawed fish , the latter including all living cartilaginous and bony fish , as well as
624-419: A protective bony cover or operculum . They are able to oxygenate their gills using muscles in the head. Some 400 species of fish in 50 families can breathe air, enabling them to live in oxygen-poor water or to emerge on to land. The ability of fish to do this is potentially limited by their single-loop circulation, as oxygenated blood from their air-breathing organ will mix with deoxygenated blood returning to
702-677: A royal decree of James VI (1566–1625) of Scotland . The OED speculates that shiterow is a corruption of shiteheron . Another former name was heronshaw or hernshaw , derived from Old French heronçeau . Corrupted to handsaw , this name appears in Shakespeare 's Hamlet . A possible further corruption took place in the Norfolk Broads, where the heron is often referred to as a harnser . The herons are medium- to large-sized birds with long legs and necks. They exhibit very little sexual dimorphism in size. The smallest species
780-441: A sense of touch and of hearing . Blind cave fish navigate almost entirely through the sensations from their lateral line system. Some fish, such as catfish and sharks, have the ampullae of Lorenzini , electroreceptors that detect weak electric currents on the order of millivolt. Vision is an important sensory system in fish. Fish eyes are similar to those of terrestrial vertebrates like birds and mammals, but have
858-514: A study of little egrets and cattle egrets in India, the majority of the colonies surveyed contained both species. Nesting is seasonal in temperate species; in tropical species, it may be seasonal (often coinciding with the rainy season) or year-round. Even in year-round breeders, nesting intensity varies throughout the year. Tropical herons typically have only one breeding season per year, unlike some other tropical birds which may raise up to three broods
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#1732780417746936-485: A tail fin, jaws, skin covered with scales , and lays eggs. Each criterion has exceptions, creating a wide diversity in body shape and way of life. For example, some fast-swimming fish are warm-blooded, while some slow-swimming fish have abandoned streamlining in favour of other body shapes. Fish species are roughly divided equally between freshwater and marine (oceanic) ecosystems; there are some 15,200 freshwater species and around 14,800 marine species. Coral reefs in
1014-589: A true "land fish" as this worm-like catfish strictly lives among waterlogged leaf litter . Cavefish of multiple families live in underground lakes , underground rivers or aquifers . Like other animals, fish suffer from parasitism . Some species use cleaner fish to remove external parasites. The best known of these are the bluestreak cleaner wrasses of coral reefs in the Indian and Pacific oceans. These small fish maintain cleaning stations where other fish congregate and perform specific movements to attract
1092-422: A typical fish is adapted for efficient swimming by alternately contracting paired sets of muscles on either side of the backbone. These contractions form S-shaped curves that move down the body. As each curve reaches the tail fin, force is applied to the water, moving the fish forward. The other fins act as control surfaces like an aircraft's flaps, enabling the fish to steer in any direction. Since body tissue
1170-583: A variety of live aquatic prey. Their diet includes a wide variety of aquatic animals, including fish, reptiles, amphibians , crustaceans , molluscs , and aquatic insects. Individual species may be generalists or specialize in certain prey types, such as the yellow-crowned night heron , which specializes in crustaceans, particularly crabs . Many species also opportunistically take larger prey, including birds and bird eggs, rodents, and more rarely carrion . Even more rarely, herons eating acorns, peas, and grains have been reported, but most vegetable matter consumed
1248-522: A year. Courtship usually takes part on the nest . Males arrive first and begin the building of the nest, where they display to attract females. During courtship, the male employs a stretch display and uses erectile neck feathers; the neck area may swell. The female risks an aggressive attack if she approaches too soon and may have to wait up to four days. In colonial species, displays involve visual cues, which can include adopting postures or ritual displays, whereas in solitary species, auditory cues, such as
1326-411: Is absent. Generally, herons lay between three and seven eggs . Larger clutches are reported in the smaller bitterns and more rarely some of the larger day herons, and single-egg clutches are reported for some of the tiger herons. Clutch size varies by latitude within species, with individuals in temperate climates laying more eggs than tropical ones. On the whole, the eggs are glossy blue or white, with
1404-402: Is accidental. The most common hunting technique is for the bird to sit motionless on the edge of or standing in shallow water and to wait until prey comes within range. Birds may either do this from an upright posture, giving them a wider field of view for seeing prey or from a crouched position, which is more cryptic and means the bill is closer to the prey when it is located. Having seen prey,
1482-465: Is an important sensory system in fish. Fish sense sound using their lateral lines and otoliths in their ears, inside their heads. Some can detect sound through the swim bladder. Some fish, including salmon, are capable of magnetoreception ; when the axis of a magnetic field is changed around a circular tank of young fish, they reorient themselves in line with the field. The mechanism of fish magnetoreception remains unknown; experiments in birds imply
1560-431: Is denser than water, fish must compensate for the difference or they will sink. Many bony fish have an internal organ called a swim bladder that allows them to adjust their buoyancy by increasing or decreasing the amount of gas it contains. The scales of fish provide protection from predators at the cost of adding stiffness and weight. Fish scales are often highly reflective; this silvering provides camouflage in
1638-521: Is generally long and harpoon-like. It can vary from extremely narrow, as in the agami heron , to wider as in the grey heron . The most atypical heron bill is owned by the boat-billed heron , which has a broad, thick bill. Herons' bills and other bare parts of the body are usually yellow, black, or brown in colour, although this can vary during the breeding season. The wings are broad and long, exhibiting 10 or 11 primary feathers (the boat-billed heron has only nine), 15–20 secondaries, and 12 rectrices (10 in
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#17327804177461716-486: Is now placed with 12 other species in the genus Egretta that was introduced in 1817 by the German naturalist Johann Reinhold Forster . The genus name comes from the Provençal French for the little egret , aigrette , a diminutive of aigron , "heron". The specific epithet sacra is from Latin sacer meaning "sacred". The Pacific reef heron is referred to by a variety of names by the indigenous peoples of
1794-500: Is now regarded as a member of the Ardeidae. Although herons resemble birds in some other families, such as the storks , ibises , spoonbills , and cranes , they differ from these in flying with their necks retracted, not outstretched. They are also one of the bird groups that have powder down . Some members of this group nest colonially in trees, while others, notably the bitterns, use reed beds . A group of herons has been called
1872-465: Is the biggest part of the brain; it is small in hagfish and lampreys , but very large in mormyrids , processing their electrical sense . The brain stem or myelencephalon controls some muscles and body organs, and governs respiration and osmoregulation . The lateral line system is a network of sensors in the skin which detects gentle currents and vibrations, and senses the motion of nearby fish, whether predators or prey. This can be considered both
1950-645: Is unclear at the moment, and molecular studies have so far suffered from studying only a small number of taxa. Especially among the subfamily Ardeinae, the relationships are very inadequately resolved. The arrangement presented here should be considered provisional. A 2008 study suggests that this family belongs to the Pelecaniformes . In response to these findings, the International Ornithological Congress reclassified Ardeidae and their sister taxa Threskiornithidae under
2028-400: Is usually considered the dwarf bittern , which measures 25–30 cm (10–12 in) in length, although all the species in the genus Ixobrychus are small and many broadly overlap in size. The largest species of heron is the goliath heron , which stands up to 152 cm (60 in) tall. All herons can retract their necks by folding them into a tight S-shape, due to the modified shape of
2106-617: The Gnathostomata or (for bony fish) Osteichthyes , also contains the clade of tetrapods (four-limbed vertebrates, mostly terrestrial), which are usually not considered fish. Some tetrapods, such as cetaceans and ichthyosaurs , have secondarily acquired a fish-like body shape through convergent evolution . Fishes of the World comments that "it is increasingly widely accepted that tetrapods, including ourselves, are simply modified bony fishes, and so we are comfortable with using
2184-723: The Indo-Pacific constitute the center of diversity for marine fishes, whereas continental freshwater fishes are most diverse in large river basins of tropical rainforests , especially the Amazon , Congo , and Mekong basins. More than 5,600 fish species inhabit Neotropical freshwaters alone, such that Neotropical fishes represent about 10% of all vertebrate species on the Earth. Fish are abundant in most bodies of water. They can be found in nearly all aquatic environments, from high mountain streams (e.g., char and gudgeon ) to
2262-515: The Pacific reef heron , both dark and light colour morphs exist, and the percentage of each morph varies geographically; its white morphs only occur in areas with coral beaches. The herons are a widespread family with a cosmopolitan distribution . They exist on all continents except Antarctica and are present in most habitats except the coldest extremes of the Arctic, extremely high mountains, and
2340-572: The Paleozoic , diversifying into many forms. The earliest fish with dedicated respiratory gills and paired fins , the ostracoderms , had heavy bony plates that served as protective exoskeletons against invertebrate predators . The first fish with jaws , the placoderms, appeared in the Silurian and greatly diversified during the Devonian , the "Age of Fishes". Bony fish, distinguished by
2418-571: The Silurian , with giant armoured placoderms such as Dunkleosteus . Jawed fish, too, appeared during the Silurian: the cartilaginous Chondrichthyes and the bony Osteichthyes . During the Devonian , fish diversity greatly increased, including among the placoderms, lobe-finned fishes, and early sharks, earning the Devonian the epithet "the age of fishes". Fishes are a paraphyletic group, since any clade containing all fish, such as
Pacific reef heron - Misplaced Pages Continue
2496-477: The abyssal and even hadal depths of the deepest oceans (e.g., cusk-eels and snailfish ), although none have been found in the deepest 25% of the ocean. The deepest living fish in the ocean so far found is a cusk-eel, Abyssobrotula galatheae , recorded at the bottom of the Puerto Rico Trench at 8,370 m (27,460 ft). In terms of temperature, Jonah's icefish live in cold waters of
2574-651: The grey heron is mostly sedentary in Britain, but mostly migratory in Scandinavia. Birds are particularly inclined to disperse widely after breeding, but before the annual migration, where the species is colonial, searching out new feeding areas and reducing the pressures on feeding grounds near the colony. The migration typically occurs at night, usually as individuals or in small groups. The herons, egrets and bitterns are carnivorous . The members of this family are mostly associated with wetlands and water and feed on
2652-400: The intertidal zone , are facultative air breathers, able to breathe air when out of water, as may occur daily at low tide , and to use their gills when in water. Some coastal fish like rockskippers and mudskippers choose to leave the water to feed in habitats temporarily exposed to the air. Some catfish absorb air through their digestive tracts. The digestive system consists of a tube,
2730-493: The paleognath Lithornis vulturinus . In Buddhism, a heron symbolizes purity, transformation and the wisdom of the Buddha. In addition, as a bird that transcends elements – on the earth, in the water and in the air – the heron symbolizes the expansion of awareness and the ubiquity of consciousness. In some Native American cultures, this bird symbolizes renewal, rejuvenation and rebirth – an ever present reminder that we are all
2808-425: The stout infantfish . Swimming performance varies from fish such as tuna, salmon , and jacks that can cover 10–20 body-lengths per second to species such as eels and rays that swim no more than 0.5 body-lengths per second. A typical fish is cold-blooded , has a streamlined body for rapid swimming, extracts oxygen from water using gills, has two sets of paired fins, one or two dorsal fins, an anal fin and
2886-515: The stripe-backed bittern ( Ixobrychus involucris ) were nested with members of the genus Botaurus . Hruska and collaborators resurrected the genus Calherodius Peters , 1931 to contain two night herons (the white-backed night heron and the white-eared night heron ) that were previously placed in Gorsachius . The western cattle egret ( Bubulcus ibis ) was embedded in the genus Ardea . The eastern cattle egret ( Bubulcus coromandus )
2964-570: The Fijian island of Rotuma , conducted in 1991 and 2018, suggest that the Pacific reef heron has recently colonized the island. New Zealand is considered to be the southern limit of the Pacific reef heron's distribution. Despite being relatively uncommon, the herons are found throughout the country, though are most common in Northland . The species lay clutches of eggs year-round in colonies in
3042-521: The IOC lists 74 heron species, divided into 18 genera. Other prehistoric and fossil species are included in the respective genus accounts. In addition, Proherodius is a disputed fossil which was variously considered a heron or one of the extinct long-legged waterfowl , the Presbyornithidae . It is only known from a sternum ; a tarsometatarsus that had been assigned to it actually belongs to
3120-557: The Oxford English Dictionary describes the use of shitepoke for the small green heron of North America ( Butorides virescens ) as originating in the United States, citing a published example from 1853. The OED also observes that shiterow or shederow are terms used for herons, and also applied as derogatory terms meaning a thin, weakly person . This name for a heron is found in a list of game birds in
3198-826: The Pacific region. In New Zealand , multiple names have been given, including kākatai , matuku moana and matuku tai . It is known as belō in Fiji, matu'u in the Samoan Islands , and motuku in Niue , Tonga , and Wallis Island . Two subspecies are recognised: Pacific reef herons are medium-sized herons, reaching 57 to 66 cm (22 to 26 in) in length. They have a wingspan of between 90 and 110 cm (35 and 43 in) and reach an average weight of 400 g (14 oz). The species displays an unusual, non-sexual dimorphism , with some members having entirely white plumage ('light' morph) and others (the larger portion) being charcoal-grey ('dark' morph). The reason for
Pacific reef heron - Misplaced Pages Continue
3276-601: The Southern Ocean, including under the Filchner–Ronne Ice Shelf at a latitude of 79°S, while desert pupfish live in desert springs, streams, and marshes, sometimes highly saline, with water temperatures as high as 36 C. A few fish live mostly on land or lay their eggs on land near water. Mudskippers feed and interact with one another on mudflats and go underwater to hide in their burrows. A single undescribed species of Phreatobius has been called
3354-556: The attention of the cleaners. Cleaning behaviors have been observed in a number of fish groups, including an interesting case between two cichlids of the same genus, Etroplus maculatus , the cleaner, and the much larger E. suratensis . Fish occupy many trophic levels in freshwater and marine food webs . Fish at the higher levels are predatory , and a substantial part of their prey consists of other fish. In addition, mammals such as dolphins and seals feed on fish, alongside birds such as gannets and cormorants . The body of
3432-407: The bitterns). The feathers of the herons are soft and the plumage is usually blue, black, brown, grey, or white, and can often be strikingly complex. Amongst the day herons, little sexual dimorphism in plumage is seen (except in the pond-herons); however, for the night herons and smaller bitterns, plumage differences between the sexes are the rule. Many species also have different colour morphs . In
3510-550: The body, and produce a concentrated urine. The reverse happens in freshwater fish : they tend to gain water osmotically, and produce a dilute urine. Some fish have kidneys able to operate in both freshwater and saltwater. Fish have small brains relative to body size compared with other vertebrates, typically one-fifteenth the brain mass of a similarly sized bird or mammal. However, some fish have relatively large brains, notably mormyrids and sharks , which have brains about as large for their body weight as birds and marsupials . At
3588-526: The cervical vertebrae, of which they have 20 or 21; the neck is retracted during flight, unlike most other long-necked birds. The neck is longer in the day herons than the night herons and bitterns. The legs are long and strong, and in almost every species are unfeathered from the lower part of the tibia (the exception is the zigzag heron ). In flight, the legs and feet are generally held in a horizontal position, pointing backwards. Toes are long and thin, with three pointing forwards and one backwards. The bill
3666-411: The colour variation or "morph", is unknown, though it is most commonly thought to be related to camouflage. The plumage of immature herons tends to be browner and duller in colour. Pacific reef herons have yellow-grey legs, and the grey variety's throats and chins are marked by a narrow, white stripe. They have brown beaks, gold-yellow coloured eyes and the surrounding areas of their faces are normally of
3744-517: The deep booming of the bitterns, are important. The exception to this is the boat-billed heron, which pairs up away from the nesting site. Having paired, they continue to build the nest in almost all species, although in the little bittern and least bittern , only the male works on the nest. Some ornithologists have reported observing female herons attaching themselves to impotent mates, then seeking sexual gratification elsewhere. The nests of herons are usually found near or above water. Although
3822-433: The driest deserts. Almost all species are associated with water; they are essentially non-swimming waterbirds that feed on the margins of lakes, rivers, swamps, ponds, and the sea. They are predominantly found in lowland areas, although some species live in alpine areas, and the majority of species occur in the tropics. The herons are a highly mobile family, with most species being at least partially migratory ; for example,
3900-570: The exact root is unknown; some authorities reconstruct a Proto-Indo-European root * peysk- , attested only in Italic , Celtic , and Germanic . About 530 million years ago during the Cambrian explosion , fishlike animals with a notochord and eyes at the front of the body, such as Haikouichthys , appear in the fossil record . During the late Cambrian , other jawless forms such as conodonts appear. Jawed vertebrates appear in
3978-403: The exception being the large bitterns, which lay olive-brown eggs. Analyses of skeletons, mainly skulls , suggested that the Ardeidae could be split into a diurnal and a crepuscular / nocturnal group which included the bitterns. From DNA studies, and from skeletal analyses that focussed more on bones of the body and limbs, that two-group division has been revealed to be incorrect. Rather,
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#17327804177464056-445: The extinct placoderms and acanthodians . Most fish are cold-blooded , their body temperature varying with the surrounding water, though some large active swimmers like white shark and tuna can hold a higher core temperature . Many fish can communicate acoustically with each other, such as during courtship displays . The earliest fish appeared during the Cambrian as small filter feeders ; they continued to evolve through
4134-586: The family Ardeidae , with 74 recognised species , some of which are referred to as egrets or bitterns rather than herons. Members of the genus Botaurus are referred to as bitterns, and, together with the zigzag heron , or zigzag bittern, in the monotypic genus Zebrilus , form a monophyletic group within the Ardeidae. Egrets do not form a biologically distinct group from herons, and tend to be named differently because they are mainly white or have decorative plumes in breeding plumage. Herons, by evolutionary adaptation, have long beaks. The classification of
4212-468: The feet are used to flush out hidden prey. The wings may be used to frighten prey (or possibly attract it to shade) or to reduce glare; the most extreme example of this is exhibited by the black heron , which forms a full canopy with its wings over its body. Some species of heron, such as the little egret and grey heron, have been documented using bait to lure prey to within striking distance. Herons may use items already in place, or actively add items to
4290-405: The front of the brain are the olfactory lobes , a pair of structures that receive and process signals from the nostrils via the two olfactory nerves . Fish that hunt primarily by smell, such as hagfish and sharks, have very large olfactory lobes. Behind these is the telencephalon , which in fish deals mostly with olfaction. Together these structures form the forebrain. Connecting the forebrain to
4368-412: The gills flows in the opposite direction to the water, resulting in efficient countercurrent exchange . The gills push the oxygen-poor water out through openings in the sides of the pharynx. Cartilaginous fish have multiple gill openings: sharks usually have five, sometimes six or seven pairs; they often have to swim to oxygenate their gills. Bony fish have a single gill opening on each side, hidden beneath
4446-532: The gills. Oxygen-rich blood then flows without further pumping, unlike in mammals, to the body tissues. Finally, oxygen-depleted blood returns to the heart. Fish exchange gases using gills on either side of the pharynx . Gills consist of comblike structures called filaments. Each filament contains a capillary network that provides a large surface area for exchanging oxygen and carbon dioxide . Fish exchange gases by pulling oxygen-rich water through their mouths and pumping it over their gills. Capillary blood in
4524-447: The gut, leading from the mouth to the anus. The mouth of most fishes contains teeth to grip prey, bite off or scrape plant material, or crush the food. An esophagus carries food to the stomach where it may be stored and partially digested. A sphincter, the pylorus, releases food to the intestine at intervals. Many fish have finger-shaped pouches, pyloric caeca , around the pylorus, of doubtful function. The pancreas secretes enzymes into
4602-424: The head is moved from side to side, so that the heron can calculate the position of the prey in the water and compensate for refraction , and then the bill is used to spear the prey. In addition to sitting and waiting, herons may feed more actively. They may walk slowly, around or less than 60 paces a minute, snatching prey when it is observed. Other active feeding behaviours include foot stirring and probing, where
4680-457: The heart from the rest of the body. Lungfish, bichirs, ropefish, bowfins, snakefish, and the African knifefish have evolved to reduce such mixing, and to reduce oxygen loss from the gills to oxygen-poor water. Bichirs and lungfish have tetrapod-like paired lungs, requiring them to surface to gulp air, and making them obligate air breathers. Many other fish, including inhabitants of rock pools and
4758-423: The herons, cranes and egrets in the genus Ardea and coined the binomial name Ardea sacra . Gmelin based his description on the "Sacred heron" that had been described in 1785 by the English ornithologist John Latham in his multi-volume work A General Synopsis of Birds . The naturalist Joseph Banks had provided Latham with a specimen of a white morph that had been collected on Tahiti. The Pacific reef heron
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#17327804177464836-480: The individual heron/egret species is fraught with difficulty, and no clear consensus exists about the correct placement of many species into either of the two major genera, Ardea and Egretta . Similarly, the relationships of the genera in the family are not completely resolved. However, one species formerly considered to constitute a separate monotypic family, the Cochlearidae or the boat-billed heron ,
4914-455: The intestine to digest the food; other enzymes are secreted directly by the intestine itself. The liver produces bile which helps to break up fat into an emulsion which can be absorbed in the intestine. Most fish release their nitrogenous wastes as ammonia . This may be excreted through the gills or filtered by the kidneys . Salt is excreted by the rectal gland. Saltwater fish tend to lose water by osmosis ; their kidneys return water to
4992-506: The jungle, between palms and mangroves or in cavities of old buildings. Two to three paled greenish-blue eggs are laid in nests constructed from branches and blossoms. Males and females share brooding tasks. They normally have a 28-day brood period. After chicks are hatched, parents provide approximately five weeks of support. Their food sources are made up predominantly of varieties of ocean-based fish , crustaceans , molluscs and worms. This heron hunts during both day and night, depending on
5070-419: The midbrain is the diencephalon ; it works with hormones and homeostasis . The pineal body is just above the diencephalon; it detects light, maintains circadian rhythms, and controls color changes. The midbrain contains the two optic lobes . These are very large in species that hunt by sight, such as rainbow trout and cichlids . The hindbrain controls swimming and balance.The single-lobed cerebellum
5148-450: The nests of a few species have been found on the ground where suitable trees or shrubs are unavailable, they are typically placed in vegetation. Trees are used by many species, and here they may be placed high up from the ground, whereas species living in reed beds may nest very close to the ground. Though the majority of nesting of herons is seen in or immediately around water, colonies commonly occur in several cities when human persecution
5226-443: The nine largest families; from largest to smallest, these are Cyprinidae , Gobiidae , Cichlidae , Characidae , Loricariidae , Balitoridae , Serranidae , Labridae , and Scorpaenidae . About 64 families are monotypic , containing only one species. Fish range in size from the huge 16-metre (52 ft) whale shark to some tiny teleosts only 8-millimetre (0.3 in) long, such as the cyprinid Paedocypris progenetica and
5304-500: The ocean. Fish are caught for recreation , or raised by fishkeepers as ornaments for private and public exhibition in aquaria and garden ponds . Fish have had a role in human culture through the ages, serving as deities , religious symbols, and as the subjects of art, books and movies. The word fish is inherited from Proto-Germanic , and is related to German Fisch , the Latin piscis and Old Irish īasc , though
5382-402: The open ocean. Because the water all around is the same colour, reflecting an image of the water offers near-invisibility. Fish have a closed-loop circulatory system . The heart pumps the blood in a single loop throughout the body; for comparison, the mammal heart has two loops, one for the lungs to pick up oxygen, one for the body to deliver the oxygen. In fish, the heart pumps blood through
5460-620: The order Pelecaniformes instead of the previous order of Ciconiiformes . The cladogram shown below is based on a molecular phylogenetic study of the Ardeidae by Jack Hruska and collaborators published in 2023. For several species these results conflict with the taxonomy published online in July 2023 by Frank Gill , Pamela Rasmussen and David Donsker on behalf of the International Ornithological Committee (IOC). The least bittern ( Ixobrychus exilis ) and
5538-463: The presence of swim bladders and later ossified endoskeletons , emerged as the dominant group of fish after the end-Devonian extinction wiped out the apex placoderms. Bony fish are further divided into the lobe-finned and ray-finned fish . About 96% of all living fish species today are teleosts , a crown group of ray-finned fish that can protrude their jaws . The tetrapods , a mostly terrestrial clade of vertebrates that have dominated
5616-550: The rise and fall of the tides. During the day, it hunts in shallow waters; standing motionless with wings open like an umbrella to reduce reflections and create shade which attracts fish. In New Zealand, the Pacific reef heron has the conservation status of "Nationally endangered". It has been classified as "Regionally Critical" in the Wellington region . Heron 18 extant, see text Cochlearidae Herons are long-legged, long-necked, freshwater and coastal birds in
5694-452: The similarities in skull morphology among certain herons reflect convergent evolution to cope with the different challenges of daytime and nighttime feeding. Today, it is believed that three major groups can be distinguished, which are: The night herons may still warrant separation from the day herons and egrets (as subfamily Nycticoracinae, as it was traditionally done). However, the position of some genera (e.g. Butorides or Syrigma )
5772-439: The success rate of prey capture increased 3.6 times over solitary foraging. While the family exhibits a range of breeding strategies, overall, the herons are monogamous and mostly colonial . Most day herons and night herons are colonial, or partly colonial depending on circumstances, whereas the bitterns and tiger herons are mostly solitary nesters. Colonies may contain several species, as well as other species of waterbirds. In
5850-415: The taxon Osteichthyes as a clade, which now includes all tetrapods". The biodiversity of extant fish is unevenly distributed among the various groups; teleosts , bony fishes able to protrude their jaws , make up 96% of fish species. The cladogram shows the evolutionary relationships of all groups of living fishes (with their respective diversity ) and the tetrapods. Extinct groups are marked with
5928-702: The top trophic levels in both aquatic and terrestrial ecosystems since the Late Paleozoic , evolved from lobe-finned fish during the Carboniferous , developing air-breathing lungs homologous to swim bladders. Despite the cladistic lineage, tetrapods are usually not considered to be fish, making "fish" a paraphyletic group. Fish have been an important natural resource for humans since prehistoric times, especially as food . Commercial and subsistence fishers harvest fish in wild fisheries or farm them in ponds or in breeding cages in
6006-569: The water to attract fish such as the banded killifish . Items used may be man-made, such as bread; alternatively, striated herons in the Amazon have been watched repeatedly dropping seeds, insects, flowers, and leaves into the water to catch fish. Three species, the black-headed heron , whistling heron , and especially the cattle egret , are less tied to watery environments and may feed far away from water. Cattle egrets improve their foraging success by following large grazing animals, catching insects flushed by their movement. One study found that
6084-1125: Was not sampled. The placement of the forest bittern ( Zonerodius heliosylus ) was ambiguous, but the results suggest that it is probably closely related to members of the genus Ardeola rather than to the subfamily Tigriornithinae . Tigriornis – white-crested tiger heron Tigrisoma – tiger herons (3 species) Cochlearius – boat-billed heron Agamia – agami heron Zebrilus – zigzag heron Botaurus – bitterns (14 species of which 1 extinct, includes species formerly placed in Ixobrychus ) Gorsachius – night herons (2 species) Calherodius – white-backed night heron Oroanassa – white-eared night heron Pilherodius – capped heron Syrigma – whistling heron Egretta – herons and egrets (13 species) Nyctanassa – night herons (2 species of which 1 extinct) Nycticorax – night herons (6 species of which 4 extinct) Butorides – herons (3 species) Ardeola – pond herons (6 species) Ardea – herons and egrets (16 species, including cattle egrets) As of August 2024
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