Percoidei III

(Grunters, temperate basses and perches, snooks and giant perches, and relatives)

Class Actinopterygii

Order Perciformes

Suborder Percoidei

Number of families 7

Evolution and systematics

The suborder Percoidei contains more than 70 families and 2,800 species. This chapter focuses on the following seven families: the grunters or tigerfishes (Terapontidae: 15 genera; 48 subspecies), the temperate basses and austral perches (Percichthyidae: 11 genera; 31 subspecies), the black-fishes (Gadopsidae: 1 genus; 2 subspecies), the pygmy perches (Nannopercidae: 3 genera; 6 subspecies), the Chilean perches (Percilidae: 1 genus; 2 subspecies), the kuhlias or flagtails (Kuhliidae: 2 genera; 10 subspecies), and the snooks and giant perches (Centropomidae: 4 genera; 23 subspecies). The Percichthyidae is a loosely organized family in need of revision. Previous authors have placed the Gadopsidae, Nannopercidae, and Percilidae within this family. These fishes are recognized in this chapter as separate from the percichthyids because of disparate fin counts or their unique patterns of endemism. The blackfishes and pygmy perches are endemic to Australia, while the Chilean perches are endemic to Chile in South America. This separation has been recognized in Allen et al. (2002), and in part in Froese and Pauly (2002). The families Percichthyidae, Gadopsidae, Nannopercidae, and Percilidae, all likely date from the Eocene period. The Centropomidae date from the Cretaceous period. Freshwater grunters date back to the late Cretaceous or early Tertiary periods. Allen et al. (2002) reported that a fossil terapontid unearthed in Queensland, Australia, was dated from the Oligocene, thus indicating that grunters had been present in Australia 30 million years ago. The history of the Kuhliidae is uncertain, but the family likely dates from the Eocene.

Physical characteristics

The fishes grouped in this chapter are typically bass or perchlike in their morphology and appearance. Grunters have bodies that are oblong and compressed slightly, a sloping head with an operculum bearing two spines, and conical or flattened teeth on the jaws. Some species have enlarged "blubber lips" as adults. The dorsal fin is notched with 11–13 spines and 9–11 soft rays. There are 3 spines on the anal fin and 7–10 soft rays. The pelvic fins have 1 spine and 5 soft rays, and are positioned just behind the base of the pectoral fins. The caudal fin may be emarginate, truncate, or rounded. Grunters derive their common name from their ability to contract muscles adjacent to the swim bladder (which acts as an amplifier) to produce gruntlike sounds when alarmed, stressed, or removed from the water. They may reach at least 31.5 in (80 cm) in total length. The temperate basses and austral perches include some of the largest of freshwater fishes, and certainly among the largest perciform fishes. Many have elongate bodies and large mouths, although some have a pronounced hump or steeply sloping head. The dorsal fin is single and notched, and the anterior pelvic fin rays are elongate. Their lateral line is continuous and complete, and their scales are small, primarily ctenoid, but cycloid to a lesser extent.

Percichthyids may reach up to 71 in (180 cm) total length. Blackfishes have slender, elongate bodies; a somewhat blunt snout; a long single dorsal fin; and a somewhat long anal fin. The pelvic fins are jugular xand consist of just a single branched ray. The caudal fin is rounded. The lateral line is reasonably well developed and the scales are minute. Black-fishes may grow up to 23.6 in (60 cm) total length. Pygmy perches have small, slender bodies; small mouths; interrupted lateral lines that are poorly developed or even absent; and a notched dorsal fin. These fishes are all less than 3.9 in (10 cm) total length, and usually much shorter. Chilean perches are also small, usually less than 3.9 in (10 cm) total length, and have slender, perchlike bodies with truncate or slightly emarginate caudal fins.

Kuhlias are usually oval shaped and compressed, have large eyes relative to the size of their heads, and have a silver or grayish color. The caudal fin is forked or nearly so and often distinctly marked. The dorsal fin has 10 spines, 9–12 soft rays, and is deeply notched. The anal fin has 3 spines and 9–12 soft rays. The opercle has 2 spines, and the pelvic fins lack an axillary process. The lateral line is well developed.

Snooks and giant perches have large, elongate, perchlike bodies. The snout may be concave. Most species are silvery in color. The lateral line is continuous and extends from just behind the gill well onto the caudal fin. The caudal fin may be forked, truncate, or rounded. The dorsal fin is either deeply notched or has a pronounced gap between the first part (7–8 spines) and second part (1 spine and 8–11 soft rays). The anal fin has 3 spines and 6–9 soft rays, and the pelvic fin has 1 spine and 5 soft rays. Males and females are sexually dimorphic for body size, with females being larger. Adults range in size from 7.9 in to over 78.7 in (20–200 cm) total length. The Nile perch is the largest and grows to at least 441 lb (200 kg).

Distribution

The Terapontidae occurs in freshwater, brackish, and coastal marine waters of the Indo-Pacific. A number of them, including Amniataba (one species), Bidyanus (two subspecies), Hannia (one species), Hephaestus (13 subspecies), Pelates (three subspecies), Pelsartia (one species), Pingalla (one species), Scortum (three subspecies), Syncomistes (four subspecies), and Variichthys (two subspecies), have limited or endemic freshwater and brackish-water (some also marine) distributions in Australia and New Guinea. Others, such as Pelates and Terapon (three subspecies), are widely distributed from East Africa east to Southeast Asia, Japan, Australia, New Caledonia, and Lord Howe Island, or more narrowly in the western Pacific (for example, the monotypic Rhynchopelates oxyrhynchus). The genus Mesopristes has one species endemic to Madagascar and another to Fiji, in addition to two that occur more widely in the western Pacific. The genus Leiopotherapon has one species endemic to Luzon Island, Philippines, and another two that are endemic to Australia, whereas Lagusia micracanthus is endemic to Sulawesi, Indonesia. Pelates quadrilineatus, a wide-ranging Indo-West Pacific species, has also colonized the eastern Mediterranean from the Red Sea by way of the Suez Canal.

The Percichthyidae occurs in tropical, subtropical, and temperate marine and fresh waters of the Atlantic, Indian, and Pacific Oceans. A number have limited or endemic distributions in the fresh or brackish waters of Australia and include Bostockia (one species), Guyu (one species), Maccullochella (three subspecies, but one with two subspecies), and Macquaria (four subspecies). Percichthys (five subspecies) is endemic to freshwaters in Argentina and Chile. Coreoperca, (three subspecies), Coreosiniperca (one species) and Sinoperca (five subspecies) are endemic to freshwaters of China, Korea, and Japan. The genus Lateolabrax has two species limited to coastal, brackish, or fresh waters of Japan. Bathysphyraenops simplex is widely distributed in coastal waters of the Indo-Pacific and Atlantic regions. The four species of the genus Howella are bathypelagic in the open ocean. The closely related Gadopsidae (genus Gadopsis, two subspecies) and Nannopercidae (genus Edelia, one species; genus Nannatherina, one species; and genus Nannoperca, four subspecies) are endemic to Australia. The Percilidae (genus Percilia; two sub-species) are endemic to Chile in South America.

The Kuhliidae are distinguished by wide-ranging Indo-Pacific species (including Kuhlia mugil, K. marginata, and K. rupestris), but there are also a number of limited-distribution or endemic species. Kuhlia caudavittata is limited to fresh and brackish waters of Reunion, Mauritius, Rodriguez, and Madagascar in the Indian Ocean. The Pacific Ocean counterpart is K. boninensis, which occurs in the Ogasawara and Ryukyu Islands of Japan, but is also found at larger islands in Micronesia and also at Tahiti. Three species endemic to their localities in the Pacific region include K. munda from fresh and brackish waters in New Caledonia, K. nutabunda, a marine species from Easter Island, and K. sandivicensis from marine, brackish, and fresh waters of the Hawaiian Islands. A monotypic genus, Parakuhlia, has been reported from the Atlantic.

The family Centropomidae includes 12 species of snooks (Centropomus spp.) found in warm marine and brackish waters of the western Atlantic and eastern Pacific, from the southern United States south to Brazil in the Atlantic, and Baja California and the Gulf of California south to Peru in the Pacific. Hypoterus macropterus is endemic to Western Australia in coastal waters of the southeast Indian Ocean. Six species of Lates are endemic to the Rift Lakes of East Africa (Lakes Albert, Rudolf, Tanganyika, and Turkana) and a seventh, the notorious Nile perch (L. niloticus) is present in some Rift Lakes, but also many of the major river systems of Africa and brackish water lakes of Egypt. This species was introduced into Lake Victoria with highly disastrous effects upon the endemic and greatly diverse fish fauna. Two other species of Lates are distributed in marine, brackish, and fresh waters of the Indo-West Pacific. The Japanese giant perch (L. japonica) is found in coastal waters and streams of Japan. The highly prized barramundi (L. calcarifer) occurs in Australia and New Guinea, but can also be found from the Arabian Gulf east to China and southern Japan, and south through Indonesia. Another Indo-West Pacific species is Psammoperca waigiensis, which ranges in marine and brackish waters from the Bay of Bengal in the Indian Ocean east to Southeast Asia, China, Japan, the Philippines, and Indonesia, and south to northern Australia.

Habitat

Members of this group are found in marine, brackish, and fresh waters. Among the grunters, Amniataba occur in ponds, lakes, and reservoirs, as well as fast-flowing streams or pools in those streams; one species also ventures into mangroves in estuaries. Bidyanus and Syncomistes also occur in rivers, lakes, or reservoirs. Inhabitants of fast or occasionally slow-flowing rivers or rocky creeks include Hannia, Hephaestus, Leiopotherapon, and Pingalla. One species of Leiopotherapon has adapted to high-salinity desert waters. Scortum subspecies prefer clear streams or rivers, but are also found in lakes. Inhabitants of slow-flowing, turbid rivers and streams, or swamps include Pingalla. Lake-dwelling grunters include Hephaestus. Lagusia, Mesopristes, Pelates, Pelsartia, Rhynchopelates, and Terapon can be found in fresh and brackish water reaches of rivers and streams, or in bays.

Percichthyids are found mainly in freshwater streams, rivers, or lakes. A few species occur in reservoirs. Some species, such as Lateolabrax, also enter estuaries and are found in coastal waters. However, Howella spp. are an exception. They are pelagic in mid- or deepwater depths and migrate towards the surface at night. Some species may be benthic as adults. The blackfishes are found mainly in clear rivers or streams, sometimes at higher elevations. Pygmy perches prefer either streams and rivers, ponds, or wetlands. The Chilean perches are also found in streams.

Kuhlias inhabit coastal marine and brackish waters, usually in the water column. Some species have adapted to freshwater habitats, mainly rivers and streams, and one, K. rupestris, is well adapted to upper freshwater reaches. Juveniles of marine species frequent tide pools. The snooks and giant perches are either resident in marine or estuarine waters, usually in association with mangroves or lower freshwater reaches of rivers (i.e., Centropomus, Hypopterus, Lates, and Psammoperca) or freshwater lakes, reservoirs, and rivers (such as Lates). Adults of some species may frequent deeper water than juveniles.

Behavior

The grunters are quite variable in their general behavior. Some species are solitary and frequently associate with structures such as rocks, logs, flooded trees, or emergent vegetation. Others form large schools, often up in the water column and over deep water, or hugging the bottom in shallower water. The temperate basses and austral perches are often solitary or occur in small groups, usually in association with structure. At least one species is segregated by sex; female Australian basses (Macquaria novemaculeata) move to the upper reaches of streams, whereas males move downstream. Some species, such as the nightfishes, are nocturnal. Howella move up and down in the water column in relation to night and day. The blackfishes hug the bottom, patrol home ranges, and are active at night. Pygmy perches are often solitary and swim in midwater where they forage for prey or lurk near shelter, such as emergent vegetation. Little is known about the behavior of Chilean perches, but it is presumed that they associate with structure or the bottom. Kuhlias usually aggregate in schools and move in and out of surge zones. Species in freshwater streams often associate with structure or aggregate, as juveniles and young adults, in pools. Snooks and giant perches are often solitary, but may also occur in small groups. Many undertake seasonal migrations into estuaries, usually in relation to patterns of freshwater runoff, but some marine species also migrate into freshwater.

Feeding ecology and diet

Grunters prey upon fishes, insects, and benthic invertebrates, including crustaceans, worms, and mollusks, but some are also omnivorous or herbivorous and will feed upon benthic algae, plant roots, palm berries, or other plant life. Members of the genus Syncomistes have mouths modified for scraping algae off rock surfaces. Adult percichthyids are largely carnivores, although juveniles may feed upon zoo-plankton. Freshwater species feed upon insects, mollusks, crustaceans, fishes, fish eggs and fry, or amphibians. Some larger species will also take reptiles, birds, and even aquatic mammals. Marine and estuarine species also feed upon fishes and crustaceans; deep-dwelling species feed upon macro-plankton, crustaceans, and fishes in the water column. Black-fishes feed upon a wide range of items, including worms, insects, crustaceans, small fishes, and even fish eggs. Pygmy perches feed on terrestrial and aquatic insects (including their larvae) and microcrustaceans. Chilean perches likely also feed upon insects, crustaceans, and small fishes. Kuhlias feed upon small crustaceans and fishes, but those living in freshwater may also feed upon insects and even fruits, such as figs, that fall into the water. Snooks and giant perches are predatory fishes that feed mainly upon other fishes and crustaceans; juveniles in freshwater will also feed upon insects. They are skillful at ambushing prey. Members of the families featured in this chapter may be preyed upon by larger predator fishes and birds, and in some cases by marine and aquatic reptiles and mammals.

Reproductive biology

Mating strategies, courtship, spawning, and postspawning investment by parents is variable within this group. Freshwater grunters migrate upstream or into the shallows of lakes to spawn, usually during summer months (wet season), although occasionally between autumn and late winter (dry season). Migrations are usually triggered by changes in water temperature, rising water levels in response to seasonal rains, or both. Spawning takes place during daylight or night, may be in groups, and results in the release of eggs that fall onto the substrate. Eggs hatch within 36 hours, and the larvae develop relatively rapidly and disperse soon after. Marine species spawn in the sea and the juveniles migrate into fresh or brackish water.

The diversity of this group dictates that the reproductive biology of these fishes is variable. Age of maturity will vary both between species and within species. An example of variation within species is the nightfish Bostockia porosa. Males of this species mature after their first year, but females are not mature until their second year. Generally, freshwater percichthyids spawn during the spring and summer months, and fishes often migrate upstream or downstream to spawning sites. Many of these traditional sites have been obstructed by dams or other barriers to migration, and this has resulted in corresponding declines in population sizes of various species. Reproductive effort may be considerable in these fishes. Members of the genus Coreoperca have male parental care of eggs and larvae. The trout cod (Maccullochella macquariensis) spawns demersal eggs that are large and adhesive onto hard surfaces such as rocks. Parental care is practiced by males of this and other species in this genus. In rivers, care extends until flooding occurs; flooding makes food items, such as insect larvae, available to the postlarval fishes. In the golden perch (Macquaria ambigua), eggs are floating and no care is practiced. Others of this genus scatter eggs that are either pelagic or that sink into interstices within the substrate, and are not cared for. The reproductive biology of other freshwater species is not that well known. Among marine species, members of the genus Howella likely breed in aggregations and scatter pelagic eggs into the water column. Lateolabrax spp. spawn during winter and scatter eggs on deeper rocky reefs of coastal waters. Juveniles may migrate upriver after recruiting from the ocean. The black-fishes mature in two to three years and practice pair spawning during summer months. Females enter a male's nest and lay eggs, usually one batch that varies in number from 20–500, depending upon the species and her size, and these and the subsequent larvae are guarded by the male until they disperse. Pygmy perches are mature in about one year. Depending upon the species, spawning begins late in the austral winter (dry season) and continues through early summer (wet season). Males are territorial, assume bright colors, defend nest sites, and attract females to spawn. Females spawn multiple small batches of eggs every few days during a period that can last for several weeks. The eggs are spawned upon aquatic algae or the substrate within a male's territory. The eggs hatch within two to four days. Most adults of at least one species, Nannatherina balstoni, die after spawning. The reproductive biology of the Percilidae is not well known. Presumably, spawning also occurs sometime between the austral spring and summer. Eggs are likely demersal and may be guarded by the male.

Kuhlias in freshwater are catadromous, which means that they migrate downstream to spawn in estuaries or the open ocean. Marine species also spawn in the ocean. Tropical species may spawn all year long but seasonal peaks may occur. Spawning behavior is not well known. The spawning mode is pelagic, with spawning in groups. The eggs and larvae are pelagic; larvae of freshwater species migrate into freshwater streams and rivers.

Marine and brackish water centropomids form spawning aggregations in estuaries or reef passes. Lates spp. are catadromous and spawn in groups or pairs (not always within groups) in estuaries and nearshore waters. Females are generally larger than males, and two or more males have been observed courting much larger females. Eggs and larvae are pelagic. The reproductive behavior of African lake species of this genus is not well known, but courtship and spawning in groups or pairs, usually after migration to a specific site, with the release of pelagic eggs, is likely. Both Hypoterus macropterus and Psammoperca waigiensis probably migrate to estuaries or inshore waters to spawn pelagic eggs.

Conservation status

A good number of species of the families Percichthyidae, Gadopsidae, Nannopercidae, and Terapontidae are endemic to specific localities or have relatively small distributions, thus rendering them vulnerable to extirpation or extinction because of habitat destruction, overfishing, or the introduction of exotic species that either compete with or prey upon some life stage of the native species. For example, among the Percichthyidae, the Mary River cod (Maccullochella peelii mariensis) is listed as Critically Endangered by the IUCN. The trout cod (M. macquariensis) and the Eastern freshwater cod (M. ikei) are listed as Endangered. The mountain perch (Macquaria australasica) is classified as Data Deficient. In the Nannopercidae, the Oxleyan pygmy perch (Nannoperca oxleyana) is listed as Endangered, the Yarra pygmy perch (N. obscura) and variegated pygmy perch (N. variegata) are listed as Vulnerable. Among the Terapontidae, the silver perch (Bidyanus bidyanus), Adamson's grunter (Hephaestus adamsoni), and Yamur Lake grunter (Varia jamoerensis), are all listed as Vulnerable.

Significance to humans

A number of species are important in commercial, recreational, and subsistence fisheries, while others may be taken incidentally as aquarium fishes. Some species of grunters, temperate basses, and snooks and giant perches are also cultured for food or for release as game fishes. Certain grunters and percichthyids are also utilized in Chinese medicine.

Species accounts

List of Species

Common snook

Centropomus undecimalis

family

Centropomidae

taxonomy

Centropomus undecimalis Bloch, 1792, Jamaica, West Indies.

other common names

English: Robalo blanco; French: Crossie blanc; Spanish: Robalo blanco.

physical characteristics

Total length 55 in (140 cm); maximum weight 53.6 lb (24.3 kg). Body relatively large, elongate, and robust. Pronounced sloping forehead and snout. Color silvery with faint olive or greenish hues dorsally, lateral line is black and highly visible. Caudal fin is large and somewhat forked. There are 8–9 spines and 10 soft rays in the dorsal fin, and 3 spines and 6 soft rays in the anal fin.

distribution

Western Atlantic region, in the United States from North Carolina south to Florida, and west along the coast of the Gulf of Mexico coast as far west as Texas; south through several islands in the Caribbean to the coasts of Central and South America, and further south as far as Rio de Janeiro in Brazil.

habitat

Shallow coastal marine, brackish, and fresh waters, mainly in estuaries and lagoons and usually in association with mangroves.

behavior

Solitary, usually in association with structure but also swims in the water column. Migrates for spawning but will also migrate, for an as yet unexplained reason, into fresh water seasonally.

feeding ecology and diet

Prey on smaller benthic and inshore pelagic fishes, as well as crustaceans such as shrimps and crabs.

reproductive biology

Maturity occurs in three to five years, with smaller males maturing sooner than larger females. Lives to at least seven years. Fishes migrate seasonally, usually between May to September (but also August to July in Cuba), to estuaries or mouths of passes to court and spawn. Eggs are scattered over the bottom, and larvae are pelagic.

conservation status

Not listed by the IUCN, but vulnerable to overfishing and habitat destruction.

significance to humans

A very important commercial, subsistence, and game fish. Also raised by aquaculture.

Barramundi

Lates calcarifer

family

Centropomidae

taxonomy

Lates calcarifer Bloch, 1790, Japan.

other common names

English: Asian seabass, Barramundi perch; French: Brochet de mer.

physical characteristics

Total length 79 in (200 cm). Body large, elongate, and stout, with pronounced concave dorsal profile in head and a prominent snout. Color silvery but may be greenish or bluish gray on dorsal surfaces. Fins blackish or dusky brown. Juveniles have mottled pattern of brown with three white stripes on head and nape, and white blotches irregularly placed on back. There are 8–9 spines and 10–11 soft rays in the dorsal fin, 3 spines and 7–8 soft rays in the anal fin, and 7–8 soft rays in the pectoral fin. Caudal fin is truncate.

distribution

Indo-West Pacific from East Africa through tropical and warm temperate Asia, including southern Japan, south through Indonesia to northern Australia (from Shark Bay north in Western Australia, and the Mary River in southern Queensland in the east). Insular localities must have sufficient stream development.

habitat

Rivers and larger streams, billabongs, submerged floodplains, estuaries, and coastal waters. Juveniles migrate from the ocean upstream to the upper reaches of rivers and creeks where they shelter in vegetation, undercut banks, and other forms of structure. Adults tend to be found in lower reaches of turbid rivers and utilize holes or structure, such as submerged timber, rocks, and mangroves.

behavior

Adults and juveniles tend to be solitary, patrol home ranges near structure, and may be territorial. Migration is seasonal.

feeding ecology and diet

Voracious predator of fishes and crustaceans. Juveniles also feed on insects. Skilled at stalking or ambushing prey.

reproductive biology

Catadromous. Migrates downstream to shallow mudflats in estuaries during the wet season. Spawning occurs between September and March in Australia, with peaks in November to December and again in February to March. Females are larger than males, are highly fecund, and may be courted by one or more males at the same time. Eggs are pelagic, hatch within 24 hours, and the larvae grow quickly as they move into mangrove areas, mudflats, and floodplain lagoons. Juveniles move into coastal waters after one year, then migrate upstream where adults reside for three to four years. Populations landlocked by dams migrate to the dam face, but do not spawn. Raised extensively by aquaculture as food or for game fish-stocking programs.

conservation status

Not listed by the IUCN, but has been threatened by habitat destruction and overfishing.

significance to humans

Important as a commercial and subsistence food fish but also as a game fish. The most important commercial fish of Australia, and the most sought after game fish, generates millions of dollars per year in revenue for the sportfishing and tourist industries. Cultured fish are replacing wild-caught fishes as food in parts of Australia where netting is banned. Also important in the cultures of aboriginal Australians.

Nile perch

Lates niloticus

family

Centropomidae

taxonomy

Lates niloticus Linnaeus, 1758, Egypt.

other common names

English: African snook; French: Capitaine; German: Nilbarsch; Spanish: Perca del Nilo.

physical characteristics

Total length 76 in (193 cm); weight 441 lb (200 kg). Body large, elongate, and robust. Color silvery, with grayish blue along back and grayish silver along flank and belly. Caudal fin and portion of pectoral fin black to dark gray. There are 7–8 spines and 10–14 soft rays in the dorsal fin; the caudal fin is rounded. Free edge of operculum bears a large spine.

distribution

Africa, in fresh and occasionally brackish waters. Present in the Rift Lakes of East Africa, including Lakes Albert, Rudolph, and Tana. Introduced into Lake Victoria and others within and outside of the region, usually with catastrophic results for native fish faunas. Also occurs in major river systems including the Chad (and Lake Chad), Congo, Nile, Senegal, and Volta. Present in Lake Mariout, a brackish water body outside Alexandria, Egypt, near the Nile River.

habitat

Large lakes and major rivers and their larger tributaries; also occurs in channels and irrigation canals, brackish-water lakes, and estuaries. Larger adults prefer deeper water, smaller fishes are found in the shallows.

behavior

Swims in the water column, but may also associate with structure. Generally solitary.

feeding ecology and diet

Highly voracious predator of fishes, especially freshwater herrings in its native range, but also of cichlid fishes. Smaller fishes feed upon crustaceans and insects in shallow water.

reproductive biology

Maturity comes in two to three years; larger females reach maturity later than smaller males. The spawning season varies with latitude, temperature, and type of water body, and ranges from February to November, although shorter seasons have been reported. Presumably migrates to a specific site to court and spawn. Eggs are scattered over the bottom or in the water column, and are buoyant. Larvae are pelagic, there is no parental care.

conservation status

Not listed by the IUCN, but could be vulnerable to commercial overfishing in its native range.

significance to humans

An important commercial and subsistence food fish and game fish, raised by aquaculture for food and stocking. Stocking outside

its natural range is greatly discouraged. Introduction of this species into Lake Victoria resulted in the decimation of most of a highly diverse and evolved endemic species flock of cichlid fishes, in addition to the loss of other species endemic to that great lake. Similar effects reported elsewhere.

River blackfish

Gadopsis marmoratus

family

Gadopsidae

taxonomy

Gadopsis marmoratus Richardson, 1848, Murray River, and other rivers in South Australia.

other common names

English: Marbled river cod; German: Aalrute, Süßwasserdorsch.

physical characteristics

Total length 23.6 in (60 cm) but most, especially in smaller streams, are smaller. Body elongate, slender, and compressed laterally. Snout and caudal fin both rounded. Color is dark gray to pale brown with darker mottling on the flanks and basal portions of fins, with milky or clear color on outer portions of the fins. There are 6–8 spines and 25–28 soft rays in the dorsal fin, 3 spines and 17–19 soft rays in the anal fin, and 15 soft rays in the pectoral fins.

distribution

Murray-Darling River system of Australia, from Victoria into parts of New South Wales, Queensland and South Australia;

also northern Tasmania. Introduced into some rivers of southern Tasmania.

habitat

Submerged timber or cover in gently flowing, clear-water streams. Tolerates slightly brackish water in upper tidal reaches of streams. Tolerates extreme temperature ranges from 41–77°F (5–25°C).

behavior

Patrols home ranges and is strongly site attached.

feeding ecology and diet

Forages for insects, crustaceans, mollusks, and smaller fishes.

reproductive biology

Matures in two to three years, females take longer than males. Spawns during austral spring and summer. Female spawns a single, small batch of eggs (20–500 per batch depending upon her size) in a protected place, usually a rock crevice or hollow log within a male's home range. Hatching occurs in about 16 days and larvae remain attached to the egg case for up to 21 more days. The male defends the nest and larvae until they disperse.

conservation status

Not listed by the IUCN, but vulnerable to habitat destruction and overfishing.

significance to humans

A game fish in the southern portion of its range, but the flesh is oily and not esteemed. May be collected incidentally for aquaria.

Flagtail kuhlia

Kuhlia mugil

family

Kuhliidae

taxonomy

Kuhlia mugil Forster, 1801, Tahiti, Society Islands, Polynesia.

other common names

English: Barred flagtail, flagtail aholehole; French: Croco drapeau; Spanish: Dara bandera.

physical characteristics

Standard length 15.7 in (40 cm). Body oval shaped and compressed, the color silver, with black and white markings on the caudal fin. There are 10 spines and 9–11 soft rays in the dorsal fin, and 3 spines and 8–10 soft rays in the anal fin. The caudal fin is forked.

distribution

Widespread in the Indo-Pacific, ranging from the Red Sea and East Africa, including Madagascar, east to the Galápagos Islands, Mexico and Ecuador; also north to southern Japan, and south to Australia and Lord Howe Island. Occurs throughout Micronesia and most of Polynesia as far as Rapa.

habitat

Inshore waters along rocky and coral reefs, cliff faces, and rocks. Also enters estuaries and freshwater. Juveniles enter tide pools.

behavior

Forms tightly packed schools that swim close to structure, generally just below or in the surge zone.

feeding ecology and diet

Feeds upon small swimming crustaceans in the water column.

reproductive biology

Not well known. Probably spawns in estuaries or inshore, perhaps in schools, year round in the tropics but seasonally at higher latitudes. Eggs and larvae are pelagic.

conservation status

Not listed by the IUCN.

significance to humans

Of minor importance as a commercial and subsistence food fish. Collected for bait and for aquaria.

Jungle perch

Kuhlia rupestris

family

Kuhliidae

taxonomy

Kuhlia rupestris Lacepède, 1802, Gol Ravine, Reunion Island, Indian Ocean.

other common names

English: Freshwater aholehole, freshwater kuhlia, rock flagtail; French: Crocro sauvage; German: Felsen-Flaggenbarsch.

physical characteristics

Total length 17.7 in (45 cm), but fishes in upper reaches of freshwater streams are much smaller. Body elongate and robust compared to others in this family. Mouth is relatively large, caudal fin slightly emarginate. Color silvery or light gray with black scale margins, becomes very silvery in marine waters. Caudal fin is either black or clear, with black blotches on each caudal lobe. There are 10 spines and 11 soft rays in the dorsal fin, 3 spines and 9–10 soft rays in the anal fin, and 13–14 soft rays in the pectoral fin.

distribution

Indo-West Pacific, from East Africa east to the Ryukyu, Ogasawara, and Mariana Islands, south and east through Micronesia, Melanesia, and Polynesia on islands with freshwater streams; also to Australia as far south as Fraser Island.

habitat

Freshwater streams in coastal drainages, usually in clear waters. Also in estuaries and coastal waters seasonally.

behavior

Solitary or in small groups in fresh water. Somewhat cryptic in areas with overhanging brush, undercut banks, or other forms of structure.

feeding ecology and diet

Omnivorous, feeds upon small fishes, insects, crustaceans, and fruit that falls on the water.

reproductive biology

Catadromous, migrates to estuaries on nearshore waters to breed. Behavior not well known. Courtship and spawning

might be in schools or aggregations. Eggs and larvae are pelagic. Post-larvae migrate upstream.

conservation status

Not listed by the IUCN, but insular populations vulnerable to habitat destruction and overfishing.

significance to humans

Subsistence food fish, may also be taken in minor commercial fisheries. An important freshwater game fish in Australia and esteemed as table fare.

Southern pygmy perch

Nannoperca australis

family

Nannopercidae

taxonomy

Nannoperca australis Günther, 1861, Murray River, Australia.

other common names

German: Südaustralischer Zwergbarsch.

physical characteristics

Total length nearly 3.5 in (9 cm). Body small and elongate with relatively large, rounded caudal fin. Color silvery or pale gold (occasionally light brown), mottled with a greenish brown hue, the fins are clear. During breeding season, males have hints of orange at base of the dorsal and caudal fins, posterior portion of belly, and above eyes. Pelvic and anal fins are marked with black. There are 7–9 spines and 7–10 soft rays in the dorsal fin, 3 spines and 7–8 soft rays in the anal fin, and 11–14 soft rays in the pectoral fin.

distribution

Australia, generally coastal drainages of Victoria west to mouth of the Murray River in South Australia. Also east to inland reaches of the Murrumbidgee and Murray Rivers in Victoria and New South Wales, and south across Bass Strait to Flinders Island, King Island, and northern Tasmania. The range has contracted because of human interference with natural river flows.

habitat

Frequents submerged and emerging shoreline vegetation in streams, drains, billabongs of larger rivers, swamps, and reservoirs. Prefers still or slightly flowing water.

behavior

Forms small groups.

feeding ecology and diet

Prefers small crustaceans, and larval and adult insects.

reproductive biology

Probably matures after the first year and lives as long as five years. Likely moves to preferred spawning sites to spawn demersal eggs in small batches over the course of the season (September to January).

conservation status

Not listed by the IUCN, but vulnerable to habitat destruction.

significance to humans

May be collected for aquaria or for use as bait. An important prey of introduced species of game fishes.

Western pygmy perch

Edelia vittata

family

Percichthyidae

taxonomy

Edelia vittata Castelnau, 1873, Western Australia.

other common names

German: Westaustralischer Zwergbarsch.

physical characteristics

Total length less than 2.75 in (7 cm). Body small and somewhat ovate to elongate. Mouth small, caudal fin relatively large and rounded. Color is mottled, variably olive, brown, or gold with two orange stripes on the flank and a whitish belly. Males assume darker colors dorsally, fins become blackish, flanks mottled gold, and orange stripes deepen during breeding season. Females also change color somewhat during breeding season, assuming a bluish tinge over the bodies. Lateral line interrupted and interspersed with tubed scales. There are 7–9 spines and 8–9 soft rays in the dorsal fin, 3 spines and 6–8 soft rays in the anal fin, and 11–13 soft rays in the pectoral fin.

distribution

Endemic to the southwestern part of Western Australia; common in a number of coastal drainages, from the Philipps River near the city of Albany, north to the Arrowsmith River, about 186 mi (300 km) north of Perth.

habitat

Occurs in a variety of permanent water bodies and is somewhat tolerant of slightly brackish or tannin-stained, as well as clear, waters. Shelters in aquatic vegetation along the shorelines of lakes, ponds, wetlands, rivers, and creeks.

behavior

Generally solitary in close association with benthic algae.

feeding ecology and diet

Carnivore; feeds on benthic microcrustaceans, and adult and larval insects.

reproductive biology

Becomes mature after the first year and lives for about five years. Migrates into smaller tributary creeks or submerged flood-plains to spawn between July and November. Females lay demersal eggs in small batches for several weeks during the season.

conservation status

Not listed by the IUCN, but its relatively limited geographic distribution could make it vulnerable to habitat destruction.

significance to humans

May be collected as an aquarium fish and also used to control aquatic insects such as mosquitoes.

Japanese perch

Lateolabrax japonicus

family

Percichthyidae

taxonomy

Lateolabrax japonicus Cuvier, 1828, seas of Japan.

other common names

English: Japanese seaperch, Japan sea bass; Japanese: Suzuki.

physical characteristics

Total length 40 in (102 cm). Body elongate, compressed, and perchlike. Mouth is large, lower jaw projects beyond upper jaw. Two dorsal fins. Color silvery but with fine black spots or large black spots on adults from some localities. Juveniles have small black spots on dorsal fin and back. There are 12–15 spines and 12–14 soft rays in the dorsal fin, 3 spines and 7–9 soft rays in the anal fin. Caudal fin is truncate.

distribution

Marine, brackish, and fresh waters of Japan south and west to the South China Sea.

habitat

Inshore rocky reefs, usually in moving water. Juveniles enter brackish and fresh waters.

behavior

Solitary or in small groups. Will migrate.

feeding ecology and diet

Adults and older juveniles feed upon crustaceans, usually prawns and shrimps, and smaller fishes. Younger juveniles feed upon zooplankton.

reproductive biology

During winter months, Japanese perch migrate downstream to the sea, join conspecifics migrating from other streams, and spawn on deeper rocky reefs.

conservation status

Not listed by the IUCN, but may be vulnerable to habitat destruction, particularly in rivers and estuaries.

significance to humans

Commercial fishes and game fishes, also raised by aquaculture and collected for aquaria. Used in Chinese medicine.

Murray cod and Mary River cod

Maccullochella peelii peelii and M. peelii mariensis

family

Percichthyidae

taxonomy

Maccullochella peelii peelii Mitchell, 1838, Peel River, New South Wales, Australia. M. peelii mariensis Rowland, 1993, Mary River, Queensland, Australia.

other common names

English: Goodo, ponde.

physical characteristics

Total length (both subspecies) 80 in (180 cm); weight 250 lb (113 kg). Body large, elongate, and heavy. Body color ranges from olive to cream, occasionally yellowish, with reticulated mottling of dark gray or green along body and onto fins. Fins brownish with white edges, pelvic fin is white. Dorsal fin positioned posteriorly along back. Caudal peduncle of Mary River cod is shorter and the pelvic fins are longer than in Murray cod. Caudal fin is rounded in both subspecies. There are 10–12 spines and 13–16 soft rays in dorsal fin, 3 spines and 11–13 soft rays in anal fin, and 19–20 soft rays in pectoral fin.

distribution

Murray cod: Murray-Darling River system of Australia; absent from upper reaches of these rivers and from the smaller tributaries; its range has shrunk because of habitat destruction. Has been stocked elsewhere. Mary River cod: River Mary in Queensland, Australia, although attempts have been made to establish populations elsewhere, such as the Brisbane River.

habitat

Both subspecies favor structure, mainly submerged logs, rocks, or undercut banks, as well as deeper holes in turbid, slow flowing, or clear, rocky reaches of rivers.

behavior

Territorial and will defend a piece of habitat, usually a hole or some form of structure. Those in lakes will defend a larger area. Juveniles are migratory.

feeding ecology and diet

Carnivorous as adults and older juveniles, feeds upon macroinvertebrates, fishes, amphibians, reptiles, birds, and small terrestrial mammals that enter water. Young juveniles feed upon zooplankton.

reproductive biology

Both subspecies mature in about five to six years and may live to 60 years. Courtship and spawning occurs during the austral spring and early summer. Eggs are demersal and guarded by the male. Hatching occurs in one to two weeks to coincide with flooding that brings food for the post-larvae.

conservation status

The Murray cod is not listed, but is vulnerable to habitat destruction and overfishing. The Mary River cod is classified as Critically Endangered by the IUCN.

significance to humans

Culturally important to aboriginal peoples of Australia. Formerly important as commercial species, with overfishing and habitat destruction leading to its decline. The Murray cod is an important but highly regulated game fish.

Golden perch

Macquaria ambigua

family

Percichthyidae

taxonomy

Macquaria ambigua Richardson, 1845, Western Australia (probably an error, although Australia is the correct country).

other common names

English: Yellowbelly, Murray bream; German: Australischer Goldbarsch.

physical characteristics

Standard length 29.5 in (75 cm); weight 53 lb (24 kg); most are smaller. Base color is olive, bronze, or brownish, with distinct yellow ventral surface. Body compressed and elongate, but with concave dorsal profile of the head just above eyes, protruding lower jaw, and strongly arched nape. Caudal fin is truncate, pelvic fins have elongate filaments. There are 8–11 spines and 11–13 soft rays in the dorsal fin, 3 spines and 7–10 soft rays in the anal fin, and 15–18 pectoral fin soft rays.

distribution

Lower reaches of the Murray-Darling River system, Dawson-Fitzroy River system in southeastern Queensland, and Bulloo River and Lake Eyre drainages in New South Wales and western Victoria, Australia (the population from the latter locality may be a separate subspecies). Stocked extensively elsewhere, especially in reservoirs.

habitat

Turbid, slow-flowing rivers, billabongs, and backwaters, or in clear, fast-flowing rivers. Also in reservoirs. Favors fallen or submerged timber, overhanging banks, and rocky ledges.

behavior

Solitary; often associated with structure.

feeding ecology and diet

Adults and older juveniles favor macrocrustaceans, mollusks, and smaller fishes; juveniles forage on zooplankton over submerged floodplains.

reproductive biology

Females mature in four or more years, males in two to three years. Migrates upstream to spawn and will travel over 1,243 mi (2,000 km) to reach its spawning grounds. Courtship and spawning take place in flooded backwaters. Eggs float after spawning, hatch within 24–36 hours, and larvae disperse downstream. Barriers to migration and corresponding habitat destruction have caused serious declines in recruitment. Cultured artificially for stocking programs.

conservation status

Not listed by the IUCN, but threatened by habitat destruction.

significance to humans

Mainly a game fish, but a limited commercial fishery exists in the Murray-Darling River system.

Mountain perch

Macquaria australasica

family

Percichthyidae

taxonomy

Macquaria australasica Cuvier, 1830, Macquarie River at Bathurst, New South Wales, Australia.

other common names

English: Black bream, Macquarie perch; German: Macquaries Barsch, Silberauge.

physical characteristics

Standard length 17 in (43 cm); maximum weight 7.7 lb (3.5 kg). Base color is dark gray, silvery gray, or olive-brown, and may be mottled; the belly is often pale or light gray, and the scale margins are dark gray. Body is compressed and elongate, the dorsal profile of the head concave, the nape arched, the body deep, the eyes and jaws both large; large mucous cavities are found around the eyes and also on the preoperculum. The dorsal fin has 8–10 spines and 11–14 soft rays; the anal fin has three spines and 8–11 soft rays; there are 14–17 pectoral fin soft rays.

distribution

Middle and upper reaches of Murray River system in New South Wales and Victoria, Australia. Also known from the Yarra River system in Victoria. Introduced elsewhere. A genetically distinct population occurs in the Shoalhaven and Hawkesbury Rivers of New South Wales that may comprise a separate species.

habitat

Frequents deep holes on the bottom, but will move up into midwater in streams or reservoirs.

behavior

Adults are solitary but form aggregations inshore and when migrating.

feeding ecology and diet

Forages for aquatic insects, crustaceans, and mollusks. Post-larvae feed on zooplankton.

reproductive biology

Males mature in two years, females in three. Females larger than males. Forms small aggregations that migrate upstream to spawn. Spawning takes place between October and December. Courtship occurs over rocky or gravel bottoms above riffle stretches and demersal eggs are released to scatter onto the bottom; eggs usually slip between interstices of substrate. Eggs hatch in 13–18 days. No parental care.

conservation status

Classified as Data Deficient by the IUCN. Likely vulnerable to habitat destruction and losses from introduced parasites.

significance to humans

Primarily a game fish, but also a minor component of commercial and aquarium fisheries.

Sooty grunter

Hephaestus fuliginosus

family

Terapontidae

taxonomy

Hephaestus fuliginosus Macleay, 1883, Upper Burdekin River, north Queensland, Australia.

other common names

English: Black bream; German: Rußiger Grunzbarsch.

physical characteristics

Reaches 17.7 in (45 cm) total length, but usually smaller in smaller streams. The body is typical of freshwater grunters. Silvery olive in color. There are 11–12 spines and 12–14 soft rays in the dorsal fin, 3 spines and 8–10 soft rays in the anal fin, and 15–17 pectoral fin rays. Lower jaw is distinguished by a discontinuous lip fold.

distribution

Australia, from north coastal Queensland (Cape Hillsborough) to the Gulf of Carpentaria and west to the Daly River in the Northern Territory. Replaced by H. jenkinsi in northwestern Australia, including the Kimberly Region of Western Australia.

habitat

Sandy or rocky bottoms in the upper reaches of large, flowing streams; also in reservoirs. Tolerates a considerable range of temperatures and moderately acidic conditions.

behavior

Solitary or in groups, usually in association with submerged plants or other forms of structure.

feeding ecology and diet

Omnivorous, feeds upon invertebrates, amphibians, algae, roots of emergent plants, and fruits that fall upon the water.

reproductive biology

Migrates to spawn in groups during summer months; spawning migration is triggered by rains. Eggs are demersal.

conservation status

Not listed by the IUCN.

significance to humans

Important as a game fish in Australia.

Target perch

Terapon jarbua

family

Terapontidae

taxonomy

Terapon jarbua Forsskål, 1775, Jidda, Saudi Arabia, Red Sea.

other common names

English: Crescent-banded tiger-fish, tiger grunter, tiger perch; French: Peau d'âne, relégué, violon jarbua; Spanish: Baraonga jarbúa.

physical characteristics

Total length 14.2 in (36 cm). Body typically perchlike but more elongate. Silvery to light tan in color, with cream on belly and series of black stripes along flank and onto caudal fin. Caudal fin has black tips. There are 11–12 spines and 9–11 soft rays in the dorsal fin, 3 spines and 7–10 soft rays in the anal fin. Lower-most spine on the operculum extends beyond the opercular flap.

distribution

Indo-Pacific, from the Red Sea and East Africa east to Samoa, north to southern Japan, and south to Australia and Lord Howe Island.

habitat

Marine and brackish waters, usually in bays, mangroves, and estuaries; will enter rivers. Both adults and juveniles frequent sand flats inshore, but juveniles will enter intertidal zone.

behavior

Solitary or in small groups that move about the bottom or around structure.

feeding ecology and diet

Omnivorous, feeds upon fishes, insects, benthic invertebrates, and algae.

reproductive biology

Catadromous in rivers. Probably spawns in groups in the saltwater. Eggs and larvae are pelagic. Juveniles migrate into lower reaches of rivers.

conservation status

Not listed by the IUCN.

significance to humans

Minor commercial species also taken in subsistence fisheries; incidental game fishes. Juveniles are collected for the aquarium trade. Also raised in aquaculture.

Resources

Books

Allen, G. R., S. H. Midgley, and M. Allen. Field Guide to the Freshwater Fishes of Australia. Perth: Western Australian Museum, 2002.

Eschmeyer, W. N., ed. Catalog of Fishes. 3 vols. San Francisco: California Academy of Sciences, 1998.

Helfman, G. S., B. B. Collette, and D. E. Facey. The Diversity of Fishes. Oxford: Blackwell Science, 1997.

Leis, J. M., and B. M. Carson-Ewart, eds. The Larvae of Indo-Pacific Coastal Fishes. Boston: Brill, 2000.

Masuda, H., K. Amaoka, C. Araga, T. Uyeno, and T. Yoshino, eds. The Fishes of the Japanese Archipelago. Tokyo: Tokai University Press, 1984.

Myers, R. F. Micronesian Reef Fishes. 3rd edition. Barrigada, Guam: Coral Graphics, 1999.

Nelson, J. S. Fishes of the World. 2nd edition. New York: John Wiley & Sons, 1994.

Thresher, R. E. Reproduction in Reef Fishes. Neptune City, NJ: T.F.H. Publications, 1984.

Organizations

IUCN/SSC Coral Reef Fishes Specialist Group. International Marinelife Alliance-University of Guam Marine Laboratory, UOG Station, Mangilao, Guam 96913 USA. Phone: (671) 735-2187. Fax: (671) 734-6767. E-mail: donaldsn@uog9.uog.edu Web site: <http://www.iucn.org/themes/ssc/sgs/sgs.htm>

Terry J. Donaldson, PhD