Asian Seabass

All bony fishes have lateral lines which can be used to sense pressure and to judge underwater currents and localized movements in the water. The barramundi lateral line extends onto the caudal fin. Barramundi have reflective eyes which allow them to see better in dark conditions. Barramundi also have a sense of smell. Modes of communication in barramundi are poorly understood.

Perception Channels: visual ; tactile ; acoustic ; vibrations ; chemical

This species is not listed as threatened or endangered by any international organization.

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

Barramundi are serially hermaphroditic, transforming from male to female at three to eight years of age (FAO, 1999; Guiguen, 1993). Moore (1979) suggests some individuals may not undergo this transition, based on a sex ratio of 3.8 males to 1 female.

Color and markings change from juveniles to adults (see "Physical Description").

Development - Life Cycle: metamorphosis

Although barramundi have not been shown to have any negative impacts, as large piscivores, they have the potential to kill off prey species if introduced into a non-native habitat. Nile Perch (Lates niloticus), are related to barramundi and are responsible for extinctions of native cichlids in Lake Victoria after having been introduced there (Morgan, 2004). According to Morgan et al. (2004), barramundi have limited potential to cause the same problems if introduced into Lake Kununurra in Western Australia.

Barramundi are valuable both as recreational and commercial fish, with a high, fairly stable price (Luna, 2008). They are stocked in lakes and ponds for recreational fishing and are also fished in freshwater creeks and estuaries (Morgan, 2004). Barramundi are heavily farmed in cages, as well as in freshwater and saltwater ponds (Webster, 2002). Worldwide capture peaked in 2000 at 74,207 metric tonnes and declined to 57,074 tonnes caught in 2005 (FAO, 2008; but see Webster, 2002). Aquaculture of barramundi has grown rapidly with 1646 tonnes (4,357,000 USD) produced in 1984, 18,564 tonnes (70,720,000 USD) produced in 1994, and 30,970 tonnes (79,034,000 USD) produced in 2005.

Since it is a white fish with delicate flavor, barramundi is also becoming popular in the United States. As of 2006, the indoor fish farming interest Australis, based in Massachusetts, was shipping 40,000 lbs of fish per week (Pierce, 2006).

Positive Impacts: food

Barramundi are predators and prey (Davis, 1985; Hitchcock, 2007; and Shine, 1986). They help support pelicans and file snakes, among other possible predators, as well as controlling the populations species on which they prey.

Barramundi are opportunistic predators. They eat microcrustaceans such as copepods and amphipods as juvenile fish under 40 mm. As larger juveniles they eat macrocrustaceans like Penaeidae and Palaemonidae. These crustacean prey are found mainly near the bottom of the water column, so this diet also protects juveniles from most of their predators, which hunt closer to the water surface. Mollusks are consumed to a lesser degree. When barramundi are around 80 mm, they begin to eat macrocrustaceans and pelagic bony fishes. Larger fish have diets of around 80% bony fish. Barramundi swallow their food whole, sucking their prey into their fairly large mouths. Moderate cannibalism is fairly common in barramundi (Davis, 1985).

Animal Foods: fish; insects; mollusks; aquatic crustaceans; other marine invertebrates; zooplankton

Primary Diet: carnivore (Piscivore , Eats non-insect arthropods, Molluscivore )

Lates calcarifer, known as barramundi, barramundi perch, giant sea perch, or Asian sea bass, is native to coastal areas in the Indian and Western Pacific Oceans. This includes coastal Australia, Southeast and Eastern Asia, and India (Luna, 2008). According to Luna, this distribution is Indo-West Pacific.

According to a 2008 study of barramundi from Burma and Australia, these fish may be two species (Ward, 2008). The study used DNA barcoding: the comparison of a particular locus (600 base pairs of the cytochrome c oxidase I gene) on the mitochondrial DNA (mtDNA). The study found that there was a significant enough difference in the mtDNA of the fish from the two locations that the species L. calcarifer may be split to take these differences into account. The study only examined fish from two locations, so Ward et al. (2008) recommended further study across the range.

Biogeographic Regions: indian ocean (Native ); pacific ocean (Native )

Barramundi are catadromous, spending most of their life in fresh water and migrating to salt water in order to breed. Smaller fish are found in rivers and streams and larger fish are found in the ocean and estuaries (Pender, 1996; FAO, 1999). There are exceptions to this patter, however, with populations of all sizes of fish found throughout their natural range. Pender and Griffin confirmed through chemical analysis that there are populations that spend their entire life cycle in salt water, in brackish water, or in fresh water (Pender, 1996). Barramundi can survive in a wide range of salinities, but must be introduced slowly to a new salinity to avoid shock (Webster, 2002). Barramundi generally prefer to hide under logs or other objects.

Barramundi are demersal, meaning they spend most of their time near but not on the bottom of a body of water. They are found at depths of ten to forty meters (Luna, 2008). In barramundi fish farming cages are generally placed two meters below the surface (Webster, 2002).

Range depth: 40 to 10 m.

Habitat Regions: tropical ; saltwater or marine ; freshwater

Aquatic Biomes: rivers and streams; coastal ; brackish water

Other Habitat Features: estuarine

Little is known about longevity of barramundi.

Barramundi are large fish, with a maximum length of over two meters, although they are more commonly around 1.5 meters. Barramundi can have a mass over 55 kilograms. According to the FAO species identification guide, they have a moderately deep, elongate, and compressed body. Barramundi have pointed snouts and large mouths, with jaws extending past the eyes. Nostrils are close together. The dorsal fin is deeply incised, with separate spiny and soft dorsal fins. The spiny dorsal fin has seven to nine spines, and the soft dorsal fin has ten to eleven soft rays. The anal fin has three spines and seven to eight soft rays. Pelvic and pectoral fins are present. These fish have a distinct caudal peduncle, or tail muscle, with a rounded caudal fin. The lateral line extends onto the caudal fin.

The scales of barramundi are firmly fixed and ctenoid. Adult barramundi are silver with darker, olive or blue-gray backs. In turbid (cloudy) water, coloration is darker. Juveniles are brown (sometimes grayish-brown) with three white stripes on the head and scattered white spots elsewhere. The markings can be dimmed or may disappear at will. The fins do not have markings. The eyes are golden-brown with a red reflective glow.

Average mass: 55 kg.

Range length: >2 (high) m.

Average length: 1.5 m.

Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry

Sexual Dimorphism: female larger

Although barramundi are opportunistic predators (Davis, 1985), they are also a prey species. The patterns present on the scales of juvenile barramundi (FAO, 1999), in combination with the fact that juveniles reside in protected mangroves and swamps (Moore, 1982; Russell, 1985; and FAO, 1999) suggests a need to protect against predators. There are several species that have been found to prey on juvenile barramundi. In an analysis of stomach contents Davis (1985) demonstrated that barramundi over 40 mm consume juvenile barramundi as part of their diet. Australian pelicans (Pelecanus conspicillatus) (Hitchcock, 2007) and file snakes (Acrochordus arafurae) (Shine, 1986) feed on both juvenile and adult barramundi.

Known Predators:

• file snakes (Acrochordus arafurae)
• Australian pelicans (Pelecanus conspicillatus)
• Barramundi (Lates calcarifer)

Anti-predator Adaptations: cryptic

Barramundi spawn seasonally (Moore, 1982). Since they are broadcast spawners (Luna, 2008; Moore, 1982), it can be inferred that there is very little social interaction among individuals. Males and females congregate for the purpose of spawning. Spawning events tend to take place at the mouths of estuaries on or near a full moon, after which tides draw the eggs up into the estuaries (Luna, 2008).

Mating System: polygynandrous (promiscuous)

Lates calcarifer is catadromous; migrating to the mouths of rivers and estuaries in order to breed (FAO, 1999; Moore, 1982; Webster, 2002; Pender, 1996; Russel; 1985). According to Moore, the eggs of fish not exposed to high salinity water do not develop fully, however, Pender and Griffen (1996) concluded that there are populations that spend their entire life cycles in freshwater, estuarine, or saltwater environments, so there may be exceptions to the requirement for high salinities.

There is one spawning season per year towards the end of the dry season and the beginning of the rainy season in the period from October to February (Moore, 1982). Females carry from 2.3 to 32.2 million eggs and can either shed them all at once or as little as 10% at a time (Moore, 1982). Because Lates calcarifer is a broadcast breeder, it can be inferred that there is little interaction between males and females. However, barramundi tend to spawn around the full moon, when tides will carry the eggs back into estuaries (Luna, 2008).

Lates calcarifer is serially hermaphroditic with males reaching maturity at 37 to 72 cm and changing into females starting at 73 cm, at around five years, three to five years, or six to eight years depending on the source (Moore, 1979, FAO, 1999; Guiguen, 1993). According to Guiguen (1993) males mature at three to five years, but this study was conducted in cage farmed fish, which may have different maturation times than wild fish. Some male specimens do get larger than 73 cm. The transition from male to female is short, lasting as little as a week, and may not occur in all individuals according to Moore (1979).

Chemical levels in the scales of fish from southern Papua New Guinea have indicated that adult barramundi do not always migrate to breeding grounds to spawn, with a lifetime non-participation rate of as much as 50% (Milton, 2005).

Breeding interval: Breeding occurs once yearly in barramundi

Breeding season: Breeding generally occurs from October to February.

Range number of offspring: 2,300,000 to 32,200,000.

Range age at sexual or reproductive maturity (female): 2 to 8 years.

Range age at sexual or reproductive maturity (male): 3 to 5 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; sequential hermaphrodite (Protandrous ); sexual ; fertilization (External ); broadcast (group) spawning; oviparous

Lates calcarifer is a nonguarding species; there is no parental involvement in the development of fry and juvenile fish (Luna, 2008).

Parental Investment: no parental involvement; pre-fertilization (Provisioning, Protecting: Female)

Caught maintly with bottom trawls, handlines, seines, gillnets, and traps. Reaches 1500-3000 g in one year in ponds under optimum conditions. Sold fresh and frozen (marketed mostly fresh); consumed steamed, pan-fried, broiled and baked.

Body elongate, compressed, with a deep caudal peduncle. Head pointed, with concave dorsal profile becoming convex in front of dorsal fin. Mouth large, slightly oblique, upper jaw reaching to behind eye; teeth villiform, no canines present. Lower edge of pre-operculum with a strong spine; operculum with a small spine and with a serrated flap above origin of lateral line. Lower first gill arch with 16 to 17 gillrakers. Scales large, ctenoid. Dorsal fin with 7 to 9 spines and 10 to 11 soft rays; a very deep notch almost dividing spiny from soft part of fin; pectoral fin short and rounded, several short, strong serrations above its base; dorsal and anal fins both have scaly sheaths. Anal fin rounded, with 3 spines and 7 to 8 short rays. Caudal fin rounded. Colour in two phases, either olive brown above with silver sides and belly (usually juveniles) or green/blue above and silver below. No spots or bars present on fins or body.

East Indian Ocean and Western central Pacific. Japanese Sea, Torres Strait or the coast of New Guinea and Darwin, Northern Territory, Queensland (Australia). Also, westward to East Africa.

To 200 cm; common between 25 and 100 cm.

A diadromous fish, inhabiting rivers before returning to the estuaries to spawn.Found in coastal waters, estuaries and lagoons,in clear to turbid water.Usually occurs at a temperature range of 26-29º C and between 10-40 m. Feeds on fishes and crustaceans.

Erilepturus Disease. Parasitic infestations (protozoa, worms, etc.)

Columnaris Disease (m.). Bacterial diseases

Lecithochirium Disease 2. Parasitic infestations (protozoa, worms, etc.)

Pseudometadena Infestation. Parasitic infestations (protozoa, worms, etc.)

Pseudometadena Disease. Parasitic infestations (protozoa, worms, etc.)

Diplectanum Disease. Parasitic infestations (protozoa, worms, etc.)

Rhapidascaris Disease (larvae). Parasitic infestations (protozoa, worms, etc.)

Epitheliocystis. Bacterial diseases

Trichodinosis. Parasitic infestations (protozoa, worms, etc.)

Lymphocystis Disease. Viral diseases

Pterobothrium Infestation 2. Parasitic infestations (protozoa, worms, etc.)

Bucephalus Disease. Parasitic infestations (protozoa, worms, etc.)

Psilostomum Disease. Parasitic infestations (protozoa, worms, etc.)

Dasyrhynchus Infestation 1. Parasitic infestations (protozoa, worms, etc.)

Gymnorhynchus Infestation. Parasitic infestations (protozoa, worms, etc.)

Serrasentis Infestation. Parasitic infestations (protozoa, worms, etc.)

Vibriosis Disease. Bacterial diseases

Vibriosis Disease (general). Bacterial diseases

Breed in estuaries throughout the Indo-Pacific. Maturing male barramundi migrate downstream from freshwater habitats at the start of the wet (monsoon) season to spawn with resident females in estuaries (Ref. 27132) and on tidal flats outside the mouths of rivers (Ref. 6390).Barramundi spawn on the full moon and new moon, primarily at the beginning of an incoming tide which carries the eggs into the estuary (Ref. 28135).Barramundi are broadcast spawners that aggregate to spawn (Ref. 6390). Spawning aggregations occur in or around the mouths of rivers (Ref. 28132). While adults and juveniles are capable of living in fresh water, brackish waters are required for embryonic development (Ref. 6136). Female barramundi are capable of producing large numbers of eggs, with estimates as high as 2.3 million eggs per kg of body weight (Ref. 28134).Barramundi are protandrous hermaphrodites, i.e., they undergo sex reversion during their life cycle. Females are generally absent in the smaller length classes, but dominate larger length classes. Most barramundi mature first as males and function as males for one or more spawning seasons before undergoing sex inversion. A few females will develop directly from immature fish (Ref. 28132). Similarly, some males may never undergo sex inversion (Ref. 28132). Also Ref. 103751.

Catadromous. Migrating from freshwater to the sea to spawn, e.g., European eels. Subdivision of diadromous. Migrations should be cyclical and predictable and cover more than 100 km.

Dorsal spines (total): 7 - 9; Dorsal soft rays (total): 10 - 11; Analspines: 3; Analsoft rays: 7 - 8

Inhabits coral reefs (Ref. 58534). Recorded as having been or being farmed in rice fields (Ref. 119549). Under hatchery conditions, larvae grow to juveniles in 26 days (Ref. 28133). The postlarvae (and possibly larvae) move from spawning areas to brackish water seasonal habitat (Ref. 28131). Larval barramundi occupy these habitats as well as main channels of streams (Ref. 6390). Juveniles live in freshwater lagoons, swamps and creeks (Ref. 28131). As these temporary habitats dry up, the juveniles move into the main stream and many migrate upstream to permanent freshwater habitats (Ref. 6390). Feed on fishes and crustaceans. They reach 1500-3000 g in one year in ponds under optimum conditions (Ref. 11046, 44894). Juveniles also eat insects (Ref. 44894).

Iridovirosis. Viral diseases

Body elongate; mouth large, slightly oblique, upper jaw extending behind the eye. Lower edge of preopercle serrated, with strong spine at its angle; opercle with a small spine and with a serrated flap above the origin of the lateral line. Caudal fin rounded.

Capsalid Monogenean Infection 1. Parasitic infestations (protozoa, worms, etc.)

Glugeosis Disease. Parasitic infestations (protozoa, worms, etc.)

Flexibacter maritimus Infection. Bacterial diseases

Rhipidocotyle Infestation 7 (Rhipidocotyle sp.). Parasitic infestations (protozoa, worms, etc.)

Cymothoa Infection. Parasitic infestations (protozoa, worms, etc.)

Cardicola Infection. Parasitic infestations (protozoa, worms, etc.)

Ectenurus Infection 2 (Ectenurus sp.). Parasitic infestations (protozoa, worms, etc.)

Lecithochirum Infestation 3. Parasitic infestations (protozoa, worms, etc.)

Aegathoa Infestation (Aegathoa sp.). Parasitic infestations (protozoa, worms, etc.)

Cycloplectanum Infection 2. Parasitic infestations (protozoa, worms, etc.)

Baldness disease in Snapper. Parasitic infestations (protozoa, worms, etc.)

Transversotrema Infestation. Parasitic infestations (protozoa, worms, etc.)

Callitetrarhynchus Disease. Parasitic infestations (protozoa, worms, etc.)

Caligus Infestation 1. Parasitic infestations (protozoa, worms, etc.)

Fish louse Infestation 1. Parasitic infestations (protozoa, worms, etc.)

Anisakis Disease (juvenile). Parasitic infestations (protozoa, worms, etc.)

White spot Disease. Parasitic infestations (protozoa, worms, etc.)

Pseudorhabdosynochus Infestation 3. Parasitic infestations (protozoa, worms, etc.)

Lernanthropus Infestation 4. Parasitic infestations (protozoa, worms, etc.)

Pseudorhabdosynochus Infestation 2. Parasitic infestations (protozoa, worms, etc.)

Cycloplectanum Infection 1. Parasitic infestations (protozoa, worms, etc.)

Found in coastal waters, estuaries and lagoons, in clear to turbid water (Ref. 5259, 44894). A diadromous fish, inhabiting rivers before returning to the estuaries to spawn. A protandrous hermaphrodite (Ref. 32209). Larvae and young juveniles live in brackish temporary swamps associated with estuaries, and older juveniles inhabit the upper reaches of rivers (Ref. 6390, 44894). Have preference for cover on undercut banks, submerged logs and overhanging vegetation (Ref. 44894). Feed on fishes and crustaceans. They reach 1500-3000 g in one year in ponds under optimum conditions (Ref. 11046, 44894). Juveniles also eat insects (Ref. 44894). Sold fresh and frozen; consumed steamed, pan-fried, broiled and baked (Ref. 9987). A very popular and sought-after fish of very considerable economic importance (Ref. 9799). Presently used for aquaculture in Thailand, Indonesia and Australia (Ref. 9799). Australia's most important commercial fish and one of the most popular angling species (Ref. 44894).

fisheries: highly commercial; aquaculture: commercial; gamefish: yes; aquarium: public aquariums; price category: very high; price reliability: reliable: based on ex-vessel price for this species

主要分布於印度-西太平洋沿岸之半淡鹹水域，西起阿拉伯灣，北至日本，南至澳洲北部。臺灣西部及南部有分布。

可以流刺網、一支釣與延繩釣等漁法捕獲。為東南亞地區之重要養殖魚種，臺灣沿海也有產，但以南部養殖較多。可清蒸、紅燒或煮湯食用。

體長而側扁，腹緣平直。頭尖，頭背側、眼睛上方有一明顯凹槽。眼略小。前後鼻孔相近。吻短而略尖。口大，下頜略突出；上頜後端達眼後下方。眶前骨與前鰓蓋骨均無鋸齒之雙重邊緣，前鰓蓋骨下緣3-4硬棘。上、下頜、鋤骨、腭骨及翼骨上均有絨毛狀齒帶，舌上無齒。被細小櫛鱗；側線鱗數60-63。背鰭單一，具深缺刻，鰭條數為VII-VIII+I, 11；臀鰭鰭條數為III+8；胸鰭短；尾鰭圓形。成魚體呈銀白色，體背側灰褐至藍灰色，各鰭灰黑或淡色；幼魚褐色至灰褐色，頭部具3條白紋，體側散布白色斑紋，眼褐色至金黃色，隨成長而略具淡紅色虹彩。

為熱帶及亞熱帶沿岸海域魚類，棲息於岩岸礁石與泥沙交匯處，而常活動於半淡鹹水水域，亦會溯入淡水河川。屬廣鹽性魚類且不耐低溫。

The barramundi (Lates calcarifer), Asian sea bass, or giant sea perch, is a species of catadromous fish in the family Latidae of the order Perciformes. The species is widely distributed in the Indo-West Pacific, spanning the waters of the Middle East, South Asia, Southeast Asia, East Asia, and Oceania.