Freshwater and Marine Fishes of Sabah

Butterflyfishes are perhaps the most familiar of reef fishes. To many people, these colorful fish are synonymous with coral reefs -- active and brilliantly colored. Most butterflyfishes are found in tropical, shallow waters, around coral reefs at depths of less than 60 feet (20 m). But, some newly-discovered species are restricted to deeper reef habitats, to 600 feet (200 m) or more. Roughly 116 species are currently known; 60 occur in Malaysia. Flittering movements and conspicuous color patterns reminiscent of butterflies may have earned this group their name. Researchers propose several possible functions for the dramatic colors and patterns of primarily yellow, black and white. For many butterflyfishes, especially closely-related species sharing similar habitat, species recognition may be important when identifying a mate. Some species live in pairs and defend a territory -- their "poster coloration" may make them more conspicuous to intruders. For others, the coloration may confer some degree of protection from predators. The black mask at the head of most butterflyfishes conceals the eye and the black marking near the tail may be a "false eyespot". Predators that mistakenly strike at the tail, rather than the head, may lose their prey. Butterflyfishes are principally day active, and seek shelter close to the reef at night. Many species assume a nocturnal color pattern that is duller than their day-time colors; others, possibly pair-bonded or territorial species, have a dramatic black/white contrast markings at night. In comparison, the Tinker’s butterflyfish has a golden mask over the eye, and contrasting white and black diagonal blocks on the body. Night-time observations made at the Waikïkï Aquarium indicate a color change that includes the development of gray bloches on top of the normal pattern.

"The blacktip reef shark is a common shallow water shark of the Indo-Pacific region and inhabits reef flats of islands and coasts of Sabah. Usually less than six feet in length, it is generally considered to be a relatively harmless species. The blacktip reef shark is named for the distinctive black tips on its dorsal (back) and pectoral (side) fins. The darker back and pale belly is an example of countershading, a kind of camouflage that makes the shark harder to see when viewed either from above or below by predators or prey. Like other sharks, the blacktip reef shark has a skeleton of flexible cartilage, reinforced with some mineral deposits. The scales, called denticles, are tooth-like in structure and very firmly embedded in the skin. Blacktip reef sharks must swim constantly with their mouths open, allowing oxygen-rich water to flow over the gills which are located in five separate slits on each side of the head. Since sharks don’t have a swim bladder like bony fishes, they will sink to the bottom if they stop swimming. Blacktips feed on smaller reef fishes, as well as on octopus and crustaceans (crabs and lobsters). Their teeth are triangular with serrated edges. Because sharks’ teeth are only loosely attached to their jaws, they may lose or break teeth as they feed. But, special tissue in the jaws keeps making sets of teeth, and the new teeth automatically move forward to replace the older ones. The blacktip reef shark’s mouth is located on the underside of its head and the jaws fold up and out of the way when the shark is swimming, a design that contributes to their streamlining. When feeding, the jaws open downward and outward, protruding slightly to take in prey. Like other sharks, the blacktip reef shark has internal fertilization. The male transfers sperm into the female's reproductive tract using sperm-transfer structures called claspers. Female blacktip reef sharks retain two to four young within their body and nourish them via a placenta-like attachment. The young sharks are released at a size of 12 to 14 inches (30-36 cm); these ""pups"" look like miniature versions of the adults and begin feeding on their own in the protected reef shallows.
This shark suffers from a parasite called a copepod that attaches itself to the cornea of the eye: Most of them have one copepod -- a whitish-yellow creature from 3 mm. to 3 inches in size -- on each eye."

"Family: CENTROPOMIDAE
Lates calcarifer (Bloch, 1790)
Common names: Sulungsung or Siakap (Malay); j * 'Mang chow' or `Jing mok lu' (Chinese); Giant sea perch (English).
DINII VIII; D2.1,10 11; A.III,8; VI,5; P.i,15; L.1.55 60; L.tr.61/2/1/13.
Body compressed. Upper profile of head more or less concave. Depth about 2.8.Head 2.7 3.0; 3.6 3.9 in total length. Eye about 7.0; equal to pointed snout; interorbital space convex, about as long as snout. Mouth slightly oblique; upper jaw with a supplemental maxillary bone which is reaching to below and behind eye. Lower jaw prominent. Nostrils approximate. Inferior border of preoperculum spinous. Absence of teeth on tongue, villiform teeth in jaws. Operculum scaly. Origin of first dorsal opposite to the 11th or 12th lateral scale, slightly behind that of ventrals. The 3rd dorsal spine the longest. Origin of second dorsal opposite to the 38th lateral scale. Base of second dorsal ending 2 scales before that of anal. Anal originating 4 scales behind that of second dorsal. Both dorsals and anal with a scaly sheath. Ventrals less than 1/2 of head, its spine as long as snout not reaching anus. Pectorals rounded, equal to eye and snout together, several short, strong serrations above its base. Caudal rounded. Least height of caudal peduncle equals to its length. Gillrakers: 15 17 on lower branch of the first arch.
Colour of fresh specimens: Greenish gray above, silvery below. Soft dorsal, anal and caudal yellowish; posterior part of anal and lower caudal fin dark or blackish. Eyes pinkish or golden colour.
Specimens examined: 160 360 mm. from Sandakan and Tawau. First record in Sabah: Sandakan, 1933.
Common size: 250 600 mm.
Geographical distribution, fishing methods and catches:
Inhabits inshore waters, bays and estuaries; grows to more than 100 mm. in length and more than 20 kg. in weight. Caught mainly by bottom gill nets, hand lines and traps. It is an excellent food fish. Marketed fresh or live at high price. It is one of the most important fish for coastal aquaculture in Sabah. The fish has been cultivated and induced to spawn under artificial conditions by the Fisheries Department in recent years, which has greatly helped to relieve shortage of Siakap fry and fingerings for the fast growing cage culture farms. Live farmed Siakap is a very popular item in the seafood restaurants in Sabah nowadays. Estimated annual catch: 700 tonne including production from cage culture farms.

"D 1.IX; D2.I,18 20; A.II,I,16 17. Lateral scutes: 27 30.
Body oblong, slightly compressed and robust. Dorsal profile strongly convex till soft dorsal, thence very slightly convex; ventral profile nearly straight from lower jaw to origin of anal. Depth 2.0 3.0. Head convex, rostro frontal profile rather steep, higher than long, 3.1 3.3. Eye about 4 in specimens 175 280 mm; 6.1 in specimen 630 mm., situated in anterior half of head, with more or less well developed adipose eye lids and mostly above longitudinal axis of body. Interorbital space about equal to snout, which is about 1.2 of eye diameter. Mouth slightly oblique; jaws equal; maxillary reaching nearly to belowhindborder of pupil. Gillrakers strong, 13 15 on lower branch of the first arch. Breast with a small naked patch anterior to ventral fins; base of pectorals also naked. Scales present on cheeks, behind eyes and upper part of operculum. Anterior portion of lateral line moderately arched, covered with about 46 scales; becoming straight below the 7th dorsal ray and covered with 27 30 scutes, the broadest of which is 3/4 diameter of eye. Fourth dorsal spine longest, about equal to 1/2 head or ventrals. Soft dorsal and anal with an elevated somewhat falcate lobe, the former a little higher than the latter, about 3/4 of head; both fins scarcely sheathed at base. Pectorals long, falciform, extending to the fourth anal ray, longer than head. Caudal deeply forked, the lobes equal.
Colour of fresh specimens: Dark greenish above, silvery below. Ventrals, anal and lower part of lower lobe of caudal yellow; spinous dorsal, margin of soft dorsal and upper lobe of caudal blackish; tips of first dorsal and anal ray white; base of pectorals black. Larger specimens with small black dots on body, head and operculum. Males are markedly darker than females.
Specimens examined: 175 630 mm., from Sandakan, Kota Kinabalu and Labuan. First record in Sabah: Sandakan, 1933.
Common size: 300 600 mm.
Geographical distribution, fishing methods and catches:
Inhabits coral and rocky reefs in coastal waters. It is one of the largest Caranx species caught in Sabah waters. Caught mainly by traps (box and fence traps), gill nets and hand lines. It is an excellent food fish, favoured by restaurants for curry dishes. Marketed fresh at high price (for large fish). Estimated annual catch: 2,000 tonneincluding Carangoides and other Caranx species. This fish is also suitable for cage culture. At the Tanjong Trayong Aquaculture Research Station, Tuaran, where cage culture experiment for C. ignobilis was conducted, it was found that a juvenile could grow to more than 630 mm. in length, weighing about 9.5 kg., in three years."

The porbeagle is a member of the group known as the mackerel sharks--Isuridae or Lamnidae--probably the most notorious of all shark families. There are only three genera, Carcharodon, Lamna, and Isurus, but in these genera can be found three of the most well-known sharks ever to swim the seas: the mako, the great white, and the extinct Megalodon. All these sharks have enough in common to classify them as a single family: they share the same fusiform, tapered shape, and the same pointed snout. They all have laterally flattened caudal keels (although the porbeagle has a secondary caudal keel as well), their tails are almost equally lobed and muscular, and they have an insignificant second dorsal fin. They all swim stiffly, flexing only the tail that is strengthened by the muscular keels, and they are capable of incredible speed. Some say the mackerel sharks are the fastest animals in the sea.

BALISTIDAE Triggerfishes, filefishes, leatherjackets
Triggerfishes are related to the puffer fish and trunk fishes. They are curiously shaped with high foreheads with the eyes also very highly placed above a longish pointed snout. Small to medium-sized fishes with deep, compressed body shape covered with minute rough scales. Gill opening reduced to small slit. First dorsal spinous and restricted to no more than three spines. Pelvic fins either absent or fused. They move by propelling themselves with their second dorsal and anal fins in an undulating motion, and only use their tails in an emergency when under threat. They vary from the colourful and aptly-named Picasso triggerfish to darker and much larger specimens. Abalistes stellaris ,Sufflamen chrysopterus Sufflamen albicaudatus .
Starry triggerfish Abalistes stellaris
Grey-green dorsally, vividly marked with small, light blue spots, blotches and 'brain' lines anteriorly. High set small eyes, small powerful jaws. First dorsal fin with three spinous rays, caudal peduncle small. Pectoral fins small and rounded, pelvic fleshy, merging with underbelly. Indo-Pacific, Arabian Gulf and east coast coral reefs, rocks and structures. These attractive trigger fishes are normally caught in fish traps and nets set for other species. 60 cm."
 

Water resource in the State is grouped into three main categories to include surface water, groundwater and marine or estuarine water. Surface water is one of the major sources of freshwater supply in Sabah. Surface water sources are from streams and rivers that flows into lakes, wetlands, watersheds and man-made reservoirs. The supply of surface water is renewable as long as there is enough percipitation. In Sabah, much of the surface water supply comes from major rivers. There are 19 river basins in sabah, with the Kinabatangan river basin on the East Coast as the largest basin covering an area of 15,385 km². The padas River on the West Coast covers an area of 8,726 km². Most of the other basins cover smaller areas.

"The State of Sabah is the second largest state in Malysia with a total land area of 73,600 km².  Sabah together with Sarawak in Borneo Island form East Malaysia. Sabah situated in the northeastern part of the island is bordered by Brunei and Sarawak in the southwest and Indonesian Kalimantan in the southern part. Sabah has a wide coastal area and is surrounded by the South China Sea and the Palawan Thrust at the northwest, the Celebes Sea at the southeast and the Sulu Sea at the east.
Sabah has a wide physiographic range and a diverse range of aquatic and terrestial habitats. Aquatic habitats range from fast flowing mountain streams to the extensive tracts of floodplain in the northeast of the State. Coastal habitats are diverse, including nipah and mangrove swamps and estuarine areas, rocky shores, sandy beaches, coastal islands and open sea. The west coast is generally more rocky and sandy against the dominance of mangrove swamps in the east coast."
 

"The large, solitary Great Barracuda lives in clear tropical waters worldwide, except in the eastern Pacific Ocean. Other species of barracuda live in muddier and shallower waters, are smaller in size, and often get together in large schools. Baracuda are warm-water fish that are known for their fierce contenance and sharp teeth. They belong to the Sphyreana family. There are five commercially important varieties of the baracuda. The great baracuda and the pacific baracuda are the most important of these five. Baracuda range from 60 to 180 cm(24-72 ins)in length although some adults can grow to more than 360 cm (12 ft) in length. The typical baracuda weighs between 2 to 4 kg (4-9lbs) Being a fish of warm tropical waters, it can ingest the organisms that create the ciguatera toxin. As a result only smaller baracuda are harvested for market.
The Great Barracuda eats fish and usually gets them by racing through a school of fish. The many large, blade-like teeth strike and injure some of the fish, and the barracuda comes back to pick up the pieces. Sometimes the barracuda just ambushes an unsuspecting fish. At dawn and dusk, when the nighttime fishes are changing places with the daytime ones, the barracuda takes advantage of the confusion to get a meal.
Though barracuda can be delicious, you have to watch out. On certain reefs, barracudas eat fish that like to eat algae containing toxic substances. By eating lots of these smaller fish, the toxins build up in the flesh of the barracuda. People who eat the barracuda are then poisoned."

Stingrays, and their flattened body shape, are usually associated with life on the seafloor.  But, here's a ray that defies the mold!  The pelagic stingray can also be found in open water, far from the shore or the ocean bottom.  This unusual species is found worldwide in tropical to temperate seas, it has been reported from the Atlantic, Central and eastern Pacific Oceans, western and southern Africa, South China Sea, Southern Japan, Tasmania, and the Mediterranean.Stingrays are related to sharks.They have a skeleton made of cartilage, the same light, flexible material that stiffens our ears and nose.  Like bottom-dwelling rays, the pelagic stingray has a compressed body shape, flattened from top to bottom.  Wing-like side fins propel the ray through the water, and the long, thin tail carries the spine that gives the group its name. Unlike bottom-dwelling rays that are dark on top and light below, the underside of the pelagic stingray is a dark grayish-purple (the origin of its scientific name).
The pelagic stingray can reach sizes up to 3 feet (90 cm), with the tail as much as twice as long as the body.  One or more venomous spines, positioned about a third of the way down the tail, are defensive weapons.  The spines have serrated edges and are covered with tissue that produces venom.  Biologists observing this ray in the waters around Hawai‘i note that other fish appear to avoid it, the spine and venom are thought to be particularly potent.  The pelagic stingray is reported to feed on small crustaceans, fish, and cephalopods.

D.IX,10; A.III,8; P.ii,10; V.I,5. L.1.16+10; L.tr.2/1/6. Body rather deep, compressed, depth 2.5-2.6, 3.1-3.3 in total length.  Head 2.7, 3.2 in total length.  Eye about 5.5, about 2 in snout, about 1.7 in convex interorbital space.  Mouth oblique, protractile; maxillary reaching to about ½ eyediameter before front border of eye.  Strong, pointed teeth in jaws in single series; anteriorly with a pair of curved canines.  Lips thick.  Dorsal profile of head more or less straight before eye, then becoming convex (adults develop a large hump on forehead that may protrude anterior to eye).  About 5 scales on preoperculum and arranged in 2 transverse rows; posterior and inferior limb of preoperculum broad and scaleless.  Lateral line interrupted, 16 scales in anterior portion and 10 in posterior portion; lateral scales: 22.  Predorsal scales rows: 4-5.  First dorsal spine equaling eye;  last spine not quite twice as long.  Membrances between dorsal spines not incised.  Soft dorsal higher than spinous part, bluntly pointed.  First anal spine short, third spine about as long as last dorsal spine.  Soft anal as high as soft dorsal.  Scaly sheath on base of dorsal and anal low.  Pectrorals about as long as ventrals, equal to snout and eye together.  Caudal slightly round. Colour of fresh specimens:  Olive to green yellowish brown.  Scales on anterior lower part of body with orange lines and figures, on rest of body scales have simple, somewhat undulating transverse lines.  Head with vomiform strikes and spots;  those on lower and under sides orange, upper sides brown and grayish; a distinct dark brown strike from posterior part of upper jaw to eye, two black strikes from hind border of eye running obliquely upwards to upper edge of operculum and three indistinct short strikes above eye.  Vertical fins with nearly vertical dark bands, as broad as interspaces.  Hind edge of caudal pinkish.  Paired fins light brownish, hyaline. Specimens examined: 168-220 mm. From Sandakan and Semporna.  First record in Sabah: Sandakan, 11th March, 1950. Common size;  300-700 mm. This fish grows to an enormours size to over 2,000 mm. In length and more than 150 kg. In weight. Inhabits coral reefs areas, feeds on mollusks, fish, sea urchins, crustaceans and other invertebrates.  It is a big fish (biggest among the wrasses or labrids) of excellent eating quality, much favoured by Chinese.  Common in East Coast markets but never occurred in large quantities.  Caught mainly by hand-lines, gill-nets and traps, throughout the year.  Marketed fresh, or live, at high price: also been exported to Hong Kong where it fetches premium price.  Estimated annual catch: 2,000 tonne-including other species of labrids and scarids.  Juveniles of this species have been cultured in flaoting cage and found to be very slow growing; however, larger fish, 600 mm. Or more in length, have been found to grow faster than the juveniles and throve well in a 3m X 3m X 2m deep cage for several years.

SPHYRNIDAE Hammerhead sharks. One of the larger sharks in the Sabah especially in the east coast. Famous in Pualau Sipadan. Two species present. Head characteristically flattened and expanded to form hammer-shape. Eyes positioned on the extremities of the head lobes. Both species considered potentially dangerous, but rarely found inshore. Fequent seasonal sightings of large numbers of hammerhead off Pualau Layang-Layang and Pualau Sipadan. Great Hammerhead Sphyrna mokarran. Front margin of head median indentation. Trailing margins of pelvic fins concave. This is a migratory species that may visit Sabah waters whilst on-passage. Feeds on other sharks, rays, fish, squid and crabs. Generally accompanied by a flotilla of pilot fish. 600 cm.

Parrotfishes, called Ikan Batu in Malay, inhabit shallow, tropical seas around the world. They are easily recognized by their parrot-like beak of fused teeth, a bluntly-rounded head, large scales, and brilliant colors. Like their relatives, the wrasses, parrotfishes have a single continuous dorsal fin and swim with lazy rowing motions of their pectoral (side) fins. Most range in size from less than 12 inches (30 cm) to nearly three feet (90 cm) in length. Some South Pacific species can reach lengths of over six feet (1.8 m). Parrotfishes travel alone or in mixed groups close to the reef. They are primarily herbivores, grazing on the fine seaweeds that grow on rock or dead coral surfaces. A few species, like the spectacled parrotfish, may also feed in part on living coral. The grooves that parrotfishes often leave on rocks or coral indicate that as they scrape the rocks for food, they also remove the underlying rock or coral skeleton as well. A pair of hard, grinding plates in the throat (pharyngeal teeth) crushes the rock into a fine powder, and after it passes through the digestive tract, it is eliminated as sand. Parrotfish are thus important reef eroders and more important in the production of sand than any other group of animals in tropical seas. It has been estimated that a large parrotfish may produce as much as a ton of sand a year!