rocky shore & coral reef fishes · 2013-08-26 · the objective of this component is to...

WildlifeCampus - Marine Field Guiding 1

Rocky Shore and Coral Reef Fishes ©

Module # 5 – Component # 2

Rocky shore & Coral reef fishes

Objective

The objective of this component is to familiarize the marine guide with the rocky shore and reef fishes of Southern Africa

Outcomes:

The learner will be able to: Describe the basic structure of rocky shore and reef fishes

Explain the feeding mechanisms of rocky shore and reef fishes Recount the reproductive processes of rocky shore and reef fishes

Recall the basic types of rocky shore and reef fishes Discuss the economical and ecological importance of rocky shore and

reef fishes

Pre-test: Test your current knowledge of marine guiding. Question 1.

Some fish have the ability to undergo a sex change (e.g. from female to male)

Yes

No



Introduction The bony fishes not only play a large part in the lives and economy of

modern humans but they are also to be marvelled at for their sheer colourfulness, beauty and diversity. There are so many species in the

ocean that trying to describe them all in this module will hardly be possible. The aim of this module therefore is rather to highlight a few

common fish and those that the marine guide is likely to encounter on

reefs and in rock-pools.

Structure Fish come in a wide range of shapes, forms and appearances with varying

functional structures that is ideally pitched to make the species survive within certain conditions. As with the sharks module we will once again

look at the differences between cartilaginous fish and bony fish

Class: Chondrichthyes Class: Osteichthyes Skeleton of mostly cartilage Skeleton of mostly bony tissue

Fins mostly rigid Fins supported by bony spines or soft rays

Numerous gill slits (5-7) Single gill cover on both sides of body Rough skinned with tooth-like plates Mostly covered with overlapping scales

Although there are some exceptions to the above rules it is relatively easy to distinguish a bony fish from a cartilaginous fish.

This brings us to a differentiating scale when it comes to descriptions of

fishes; it is aimed at helping the marine explorer to more easily identify specific families or species of fish.



Bony fish may represent virtually any combination of the above features. Certain common features are to be found on most fish and one of these is

the lateral line, which extends from above the gill opening all the way along the flanks towards the tail. The lateral line contains sensory

receptors, which are employed in sound detection. In the front of the fish the mouth can to be found to be terminal, under slung (below the head),

or extended (sticking out of the front). Just above and behind the mouth is the nostril, followed by the eye. From the eye to the first dorsal fin is an

area called the nape.

After the first dorsal fin there may be a second dorsal fin with soft

rays. The thin part just before the tail is called the caudal peduncle and on the sides of the caudal peduncle there are scutes. Fish with a thin

caudal peduncle and a rigid forked tailfin are normally fast swimming predators. Predatory fish with a reduced or rounded tailfin and a broad

peduncle are normally sluggish and rely on their ambush skills and camouflage to get a decent meal.

The anal fin is more or less below the 2nd dorsal fin on the underside of

the fish. Moving forward below the body of the fish is also a pelvic fin and on the side of the fish just behind the gill opening is the pectoral fin.

Other attachments may be tiny finlets between the 2nd dorsal fin and the tail fin (also called caudal fin). There may also be tentacles above the

nostril, eye or on the nape. A chin barbell is sometimes present.

The viscera of fish are situated behind the gill rakers and below the

vertebral column and normally contain stomach, liver, heart, the ovaries



or testis and a swim bladder. Behind the eye and embedded in the skull is

the brain and nervous chord that extends backwards through the spinal column.

Lastly the fish’s size, especially length is also a helpful indicator of

type:

Finger sized = up to 12cm Hand sized = up to 20cm

Medium = up to and around 30cm Middle sized = up to 50cm / half a meter

Large = up to a meter Very large =more than 1 meter

A “deep bodied” fish may be nearly as long or longer than it is high in

lateral view. Mostly short or robust fishes or disc-like fishes are

sometimes considered deep bodied.

Feeding

Being eaten is something that can potentially spoil your entire

day, it is however the key to a very important energy transfer system in nature. There are various energy transfer systems at work at any given

time in an ecosystem of which the most notable are the producers. The producers are the guys that can transform solar energy (Sun energy) into

malleable energy through the process of photosynthesis. Members of the plant kingdom are the primary producers and they include the green

plants, algae and mosses. In the oceans mostly alga and phytoplankton is found. Shortly on the heels of the producers are the primary consumers

or herbivores.

Herbivorous fish feed mostly by browsing on alga, scraping alga off the substrate or by filtering large amounts of phytoplankton. These plant

eating fish have the unlucky job of transforming the plant energy into body mass and protein. They also have the uncanny knack of being very

edible themselves at the best of times since they are the cows of the

ocean. This invariably gave rise to very clever and sneaky ways of convincing other life forms of the contrary, making it very difficult for the

secondary and tertiary consumers (predators) to get a decent meal. How would you feel if your food just doesn’t want to stand still!



Predation as a feeding mechanism is therefore a very advanced and

evolved skill and can take hundreds of forms. The

simplest and in many cases the most effective form of

predation entails being fast, being big and having more

and sharper teeth than your food.

This is however not good

enough anymore. Many food species became fed up

(through adaptation) with being eaten around every

corner of the ocean and

hence started the most prolific and intricate form of warfare the earth has ever seen. Being hunted most of the time goes a long way in stimulating

clever and creative ploys in averting dinner parties where you are neither host nor guest but invited.

Due to the fact that fish feed in just about any way thinkable, from

herbivore to filter feeding to vicious predator, the individual feeding regimes will be discussed under the heading “types of fishes”.

Reproduction Fertilized eggs are normally the point of departure in the life cycle of

fishes. In most cases the fertilization is external whereby the male deposits his sperm over the as yet unfertilized eggs in the water. Some

fishes may attach their eggs to the substratum or some object in the ocean. The eggs hatch rather quickly (mostly within 36 hours) into either

a larvae or a young juvenile. Larvae are more common for pelagic fish and juveniles are more common for demersal (bottom dwelling) fish.

Needless to say it takes a bit longer to hatch as a juvenile, which basically resembles the adults than a larvae, which still needs to develop into a

juvenile. The juveniles may also congregate in nurseries, mostly in secure

places like on a reef, rock pools or in the relative safety of an estuary.

Some fish species (like the wrasses) are hermaphroditic and have the ability to undergo a sex change, e.g. from a female to a male

(Protogynous) while others like the nosestripe clownfish may change from male to female (Protandrous).



Types of reef and rocky pool fishes It is advised that students also research the fishes mentioned herein on the following

website. http://www.fishbase.org/Photos/

It contains useful information and photos or graphics about most of the fishes of this

component.

Phylum: Chordata

Subphylum: Vertebrata Superclass: Pisces (Fish)

Class: Osteichthyes

Order Aulopiformes Family: Synodontidae

Lizardfish Cylindrical fish, elongate, spineless fins, mouth lined with sharp slender

teeth, teeth also on tongue.

Ecology: Voracious predator of small fish. Waits in ambush on hard or sandy

surfaces for unsuspecting prey.

Common species: Variegated lizardfish Synodus variegates (20cm, lateral band of

blotches)

Indian lizardfish Synodus indicus (19cm, lateral line of horizontal

stripes)

http://www.fishbase.org/Photos/



Order Anguilliformes

Family: Muraenidae Moray eels

Extremely elongate fish with large mouths containing numerous teeth, no

pectoral or pelvic fins.

Ecology: Normally found on rocky reefs, secretive during the day. Feeds on fish,

crustaceans and even octopus.

Common species:

Floral or snowflake moray Echidna nebulosa (75cm, white mouth,

dark cheeks, opposite blotches along body) Zebra moray Gymnomuraena zebra (115m, unique zebra

stripes)

Salt & pepper moray Gymnothorax eurostus (57cm, dark with yellow specs)

Honeycomb moray Gymnothorax favagineus (3m, honeycomb pattern)

Peppered moray Siderea picta (1.2m, light with spots over body)

Geometric moray Siderea grisea (65cm, whitish, straight lined

spots on face)

Family: Ophichtidae Snake eels

Extremely elongate fish, small P fins, head slightly deeper than body,

down-ward pointing nostrils.

Ecology: Burrowing in sand, hunts small fishes and crustaceans by sense of smell.

Common species:

Ocellated snake eel Myrichthys maculosus (50 – 100cm)



Family: Congridae

Conger and garden eels

Extremely elongate cylindrical fish, pectoral fins present, head not much deeper than body.

Ecology: Conger feeds on small fishes and crustaceans.

Garden eels feed on plankton by straining it through gills.

Common species: Blackedged conger Conger cinereus (13m, large pectoral fin,

moustache under eye)

Spotted garden eel Heteroconger hassi (35cm, upturned mouth, small P fin, spots)

Order Siluriformes

Family: Plotosidae Eel-catfish

Medium sized cylindrical elongate fish, eel shaped and pointed tail with 2

to 3 yellow stripes from snout to tail on a black background. The second dorsal and anal fins are joined to the tail fin. The first dorsal and pectoral

fins are armed with serrated venomous spines. The mouth is surrounded by eight barbells. Found on the eastern south coast and east coast.

Ecology:

Forms an advancement line as it forages for invertebrates in the soft sand and debris sometimes around reefs. The back-liners constantly swimming

over the top and forming the new front-line in a slow rolling progression.

Common Species:

Striped eel-catfish Plotosus lineatus

Order Pleuronectiformes



Family: Soleidae Flounders

Medium sized, flat, nearly round fish. Tailfin is distinct from dorsal and

anal fins. Eyes on the left side of the body.

Ecology:

Feeds on benthic invertebrates on and around flat sandy reefs of the east coast.

Common Species:

Tropical flounder Bothus mancus

Order Lophiiformes

Family: Antennariidae Angler fish (frogfish)

Small globular fish (squat and robust), limb like pectoral fins. Very large upward directed mouth (oblique), loose skin flaps and attachments. First

dorsal spine highly evolved into fishing rod tipped with a moveable lure.

Ecology:

Lies camouflaged in ambush on reefs, lures other fish with fishing rod and swallows them whole. Even fish as big as itself. Slow swimming fish but

catching action so fast that other fish in school do not realize that one has been

captured.

Common species: Painted angler Antennarius pictus (24cm, irregular dark and white

patches)

Sargassum fish Histrio histrio (20cm, mottled brown like sargassum sea weed)

Order Gobiesociformes

Family: Gobiesocidae Rocksucker



Medium sized robust cylindrical fish tapering towards the tail. The head is

broad and compressed. Pelvic fins form adhesive disc on underside of body.

Ecology:

Feeds on sea urchins and limpets, which it levers off with its long conical teeth in tidal pools around southern Africa.

Common Species:

Rocksucker Chorisochismus dentex

Order Cyprinodontiformes

Family: Hemiramphidae Halfbeaks

Medium sized straight elongate cylindrical fish with a distinctive short

upper beak and an elongate needle-like lower jaw. Dorsal and pelvic fins are set way back on the body close to the tail fin. Found on the south and

east coast.

Ecology: Skims surface waters with short upper beak open for floating plant and

animal matter. Can sometimes be seen skipping on the surface as it attempts to evade predators. Lower needle-like jaw probably used in

manoeuvring and ingesting long filamentous algae.

Common Species:

Tropical halfbeak Hyporhamphus affinis

Order Beryciformes Family: Holocentridae Soldier and squirrelfish

Mostly reddish in color, spiky dorsal fins, big eyes, anal and 2nd dorsal fins

look similar like an opposite reflection of each other.



Ecology:

Soldierfish feed on large zooplankton at night and squirrelfish feed on invertebrates and small fishes.

Common species:

Blotcheye soldier Myripristis murdjan (27cm, snout rounder than Squirrel)

Crown squirrelfish Sargocentron diadema (20cm, snout sharpish)

Order Syngnathiformes

Family: Sygnathidae

Sea Horses

Sea horses are unmistakeable with their ring-like plates, covering the

body and a tapering prehensile tail. They do not have an anal or tailfin but a single dorsal fin occurs just before the tail. South coast to east

coast. Finger sized.

Ecology: The male bears the young in a ventral pouch until they are “born”.

Common Species:

Crowned seahorse Hippocampus whitei Knysna seahorse Hippocampus capensis

Order Scorpaeniformes

Family: Scorpaenidae Scorpionfishes

Head large and spiny, dorsal fins usually notched with sharp spines within

sheaths, poisonous, skin flaps for camouflage often present, mouth large mostly oblique.

Ecology:

In or near shelter during the day on reefs or debris, most are well camouflaged, ambush hunters, feeds on crustaceans or fish.



Common species:

Popeyed scorpionfish Rhinopias frondosa (23cm, leafy appearance,

brown/yellow) Mauritius scorpionfish Sebastapiste mauritania (7cm spot on back of

first D fin) Mozambique scorpionfish Parascorpaena mossambica (l0cm,

tentacle above eye)

Raggy scorpionfish Scorpaenopsis venosa (18cm, branching growths on mandible)

Stonefish Synanceia verrucosa (35cm, globular mess, short weak tail)

Clearfin lionfish Pterois radiata (24cm, horizontal white lines on tail base)

Lionfish / devil firefish Pterois miles (38cm, P fins very large with

radiating blotches)

Order Tetraodontiformes

Family: Tetradontidae Puffers

Moderate elongate bulbous fishes with tough scales and prickly skin, small

mouth with teeth fused into a beak. Small single D. fin fairly far back above anal fin. No pelvic fin.

Ecology: Can inflate themselves greatly with water, no ribs. Feed on

Corraline benthic algae and even on corals and benthic invertebrates. Toxic to predators.

Common species:

Spotted Toby Canthigaster amboinensis (15cm, face lightish with blue

stripes, sides brown and spotted) Blackspotted puffer Arothron nigropunctatus (33cm, lightish with

dark ring around eye and mouth, sparsely spotted)

Evileye blaasop Amblyrhynchotes honkenii (30 cm, light underside, dark upperside with white spots)



Family: Ostrachiidae Boxfishes

Boxlike fishes encased in a carapace of bony plates with gaps for the

mouth, eyes, gill openings, anus, fins and tail. Mouth small, snout conical.

Ecology: Feeds on small sessile invertebrates and algae. Secretes a strong toxin to protect them against predation.

Common species:

Spotted trunkfish Ostracion meleagris (16cm, Blue with yellow spots

and dark spotted roof)

Boxy Ostracion cubicus (45cm, Yellow with white centred black spots)

Longhorn cowfish Lactoria cornuta (45cm, hexagon patterns on

body and two forward pointing horns on forehead)

Family: Monacanthidae Porky

Medium sized, compressed diamond or hatchet-shaped fish with irregular

spots. Fins are pale and first dorsal spine can be locked upright by the second spine while the pelvic fin is reduced to a single barbed spine.

Terminal mouth is very small.

Ecology: Found on southern and eastern coasts of Africa.

Common Species:

Porky Stephanolepis auratus

Family: Diodontidae

Porcupinefishes

Similar to puffers but have prominent spines over head and body, larger eyes.



Ecology:

Feed on hard shelled invertebrates crushed with its beak.

Common species:

Birdbeak burrfish Cyclichthys orbicularis (30 cm, lightish with brown spots)

Shortspine porcupinefish Diodon liturosis (60cm, large white edged

brown spots on head rump and cheeks)

Family: Balistidae Triggerfishes

Deep bodied compressed fishes like an elongate diamond. Eyes high set

and a small terminal mouth with incisiform teeth. First D.fin with large spine supported by two smaller spines (trigger mechanism).

Ecology:

Feed on wide variety including algae, zooplankton and small

invertebrates. First spine can lock into open position, can only be released by suppressing the second spine.

Common species:

Redfang triggerfish Odonus niger (50cm, dark green face, dark blue body, flowing blue tail ribbons)

Clown triggerfish Balistoides conspicillum (50cm, conspicuous white

spots on lower halve of body)

Scythe triggerfish Sufflamen bursa (24cm, light brown, darker boomerang or scythe shaped line through eye, squarish

diamond shape)

Picasso fish Rhinecanthus aculeatus (Diamond shaped, modern

art job on body)

Order Perciformes



Suborder Percoidei Family: Apogonidae Cardinalfishes

Small moderately elongate robust fishes with two D. fins, mostly with one

or two long stripes through eyes.

Ecology:

Shy during the day, ventures out at night from overhangs and holes to feed on zooplankton or small benthic invertebrates.

Common species:

Bandtail cardinal Apogon aureus (8 – 12cm, Golden with 2 blue stripes through eyes and black band around tail)

Ninestripe cardinal Apogon taeniophorus (11cm, light with h. dark

stripes ending at caudal fin)

Family: Sparidae

Sea Breams

Compressed robust perch-like fishes. Steep foreheads and small mouth. Spines prominent in fins. Dorsal fins mostly stretch from behind gill cover

down to the tail. Lateral line always visible. No scales on the snout.

Between middle-sized and large fish.

Ecology: Many Sparidae are hermaphroditic and can change sex at some stage

during the life cycle (both protogynous and protandrous change-overs occur within the Sparidae). Carnivorous, herbivorous and omnivorous.



Common sea bream species:

Name Scientific Name Feeding on Coasts

Fransmadam Boopsoidea inornata Omnivorous Lower west, south and

east

Englishman Chrysoblephus

anglicus

Crustaceans, molluscs,

fish

South and east

Roman Chrysoblephus

laticeps

Benthic predator Cape point to lower

east coast

Poenskop Cymatoceps nasutus Carnivorous on

echinoderms, molluscs,

crustaceans

Lower west, south and

lower east coasts

Blacktail Diplodus sargus

capensis

Omnivorous, juveniles

in tidal pools

All coasts

Scotsman Polysteganus

praeorbitalis

Solitary predator Eastern south and east

coasts

Musselcracker Sparodon durbanensis Molluscs, red bait and

crabs

Lower west to east

coast

Strepie Sarpa salpa Red seaweeds Lower west to east

coast

Family: Sciaenidae Kobs and croakers

Middle sized, compressed sleek fish with rounded dorsal surface and a

truncated tail. Short thick barbell on chin. First dorsal consist of two short sets with ten spines in total followed by 1 spine and a long set of rays

right up to the tail.

Ecology: Eats benthic invertebrates around the southern African coastline.

Common Species:

Baardman Umbrina canariensis

Family: Serranidae

Rockcods/bass

A large group with single elongated D fin notched or divided. From tiny goldies to the robust sea bass. Mostly predatorial. Famous for being

“bottom fished”.

Ecology:

Anthiases/goldies (Subfamily: Anthiinae) feeds on tiny crustaceans and fish eggs. The basslets/rockcods or groupers (Subfamily: Epinephelinae)



are bottom dwelling carnivores with large mouths. Some can suck fish

from crevices.

Common species:

Sea goldie Pseudoanthias squamipinis (15cm, yellow tear stripe, eye

to P fin) African basslet Lioproma africanum (8cm, small elongate with broad

head)

Coral rockcod Cephalopolis miniata (40cm, orange with blue spots)

Peacock rockcod Cephalopolis arga (40cm, dark with blue spots) Potato bass Epinephelus tukula (2cm, large oval spots on body

and fins)

Honeycomb rockcod Epinephelus merra (Large, honeycomb pattern)

Yellowbelly rockcod Epinephelus marginatus (1.5m brown with

yellow blotches)

Lyretail rockcod Variola louti (lmmature - Tailfin lunate with yellow margin)

Sixstripe soapfish Grammistes sexlineatus (25cm, dark with h. yellow stripes)



Family: Pempheridae Sweepers:

Small, compressed ovoid fishes, hatchetlike with single D Fin and

continuous anal fin. Small oblique mouth.

Ecology:

Aggregate in caves by day and disperse to feed on zooplankton by night.

Common species:

Dusky sweeper Pempheris species (15 – 20cm, coppery hatchetlike)

Family: Pomacanthidae Angelfishes

Small to medium fishes with deep compressed bodies, almost square,

small mouths and continuous D. fin. Has a prominent spine projecting backwards at the bottom of gill cover. Juveniles sometimes very

differently colored (e.g. blue with white circles or semicircles).

Ecology: Territorial on coral reefs, feeds on a variety of algae, encrusting

invertebrates, zooplankton, sponges and soft bodied invertebrates.

Common species: Old woman Pomacanthus rhomboides (46cm, Grey upper, yellow

lower and blue in the face & posterior)

Emperor angelfish P. imperator (40cm, Black mask sloping down to

gill spine, blue and yellow stripes on body)

Semicircle angelfish P.semicirculatus (38cm, elongate filaments on anal and dorsal fin, dark green speckled body)

Jumping bean Centropyge acanthops (7cm, very small, blue with

orange face and dorsal region, tailfin yellow)



Family: Pomacentridae Damselfishes

Small colorful fishes, moderately deep compressed bodies, small terminal

mouth.

Ecology:

Mostly, herbivorous or planctivorous. Some species aggressive, vigorously

guarding territory or their symbiotic anemones. The nosestripe clownfish is hermaphroditic in that a young male can develop into a female once the

dominant female is removed from the group.

Common species: Sergeant major Abudefduf variegensis(20cm five vertical black bands

across body)

Sash damsel Plectroglyphidodon leucozonus (11cm, dark, central vertical light band)

Twobar clownfish Amphiprion allardi(15c, yellow underside, dark above

with two vertical bars, 2nd bar ending sharp above belly)

Nosestripe clownfish A. akallopisos(11cm, orange, white stripe from D.fin to snout, sex change from male to female

when dominant female is removed)

Chocolate dip Chromis dimidiata(9cm, anterior chocolate, posterior white)

Domino Dascyllus trimaculatus(14cm, dark to black, juvs.

With spot on forhead and flanks, lost in adults)

Blue pete Pomacentrus caeruleus(8cm, blue upper and yellow

lower side extending into tail)

Family: Pomatomidae

Elf or Shad

Sleek compressed fish with a large mouth and a forked tail. Silvery with greenish upper (dorsal) surface. 1st dorsal fin consist of eight short spines



and 2nd dorsal fin with 23 to 28 rays. The anal fin mirrors the 2nd dorsal

fin. Large size 1.2m. Ecology:

A ferocious predator around reefs where it feeds on fish (mostly anchovies and pilchards).

Common Species: Elf / shad Pomatomus saltatrix

Family: Oplegnathidae

Knifejaws

Compressed robust to sleek fish with fused teeth that forms a parrotfish-like beak. Juveniles yellow with black bands. The caudal fin is slightly

forked but soft. Large, up to 90cm.

Ecology:

Over reefs from cape point to east coast where it feeds omnivorously on seaweeds, sponges and red bait.

Common Species:

Cape knifejaw Oplegnathus conwayi (Cape point to lower east coast)

Natal knifejaw Oplegnathus robinsoni (East coast)

Family: Mullidae

Goatfishes

Medium elongate fish with a pair of barbells on chin, 2 D fins, forked tail,

fleshy lips.

Ecology: Chemosensory barbells are thrust in sand or holes to detect prey, mostly

benthic invertebates.

Common species:

Blacksaddle goatfish Parupeneus rubescens (43cm, rosy with black saddle on top tail)

Flame goatfish Mulloidichthys vanicolensis (38cm, D yellow, Vertral



blue with conspicuous yellow line from eye to tail)

Family: Labridae Wrasses

Large and diverse group. Typical terminal mouth, mostly elongate, single unnotched D. fin, typically swim with pectoral fins in a flying manner.

Ecology:

Carnivores, planktivores and cleaners. Inactive at night. The cleaner wrasse is famous for running cleaning stations where other (even

predators) line up and pull in for a cleaning. The cleaner wrasse will even enter the predator’s mouth and clean it from parasites and dead cells

without being eaten itself.

Common species:

Diana’s hogfish Bodianus Diana (25cm, shallow forehead, spaced light

dots under dorsal fin, small dark dot on caudal fin)

Saddleback hogfish Bodianus bilunulatus (55cm, large dark saddle patch before tail)

Birdfish Gomphosus caeruleus (28cm, dark with peculiar

elongate snout)

Checkerboard wrasse Halichoeres hortulanus (27cm, blueish, head with orange lines)

Picture wrasse Halichoeres nebulosus (12cm, greenish, pink boomerang and lines on face, darker patch midbody)

Goldbar wrasse Thalosoma hebraicum (23cm, multicolored, yellow

face with blue stripes, gold bar behind face)

Bluestreak cleaner Labroides dimidiadus (11cm, whitish front, bluish rear with black lateral line widening into tailfin)

Family: Lethrinidae

Emperor



Brownish robust to sleek fish with long sloping forehead and cheeks

without scales. Single dorsal fin with ten spines. Scales have a blue centre. Between middle and large size, 75cm.

Ecology:

Preys on small crabs, worms and benthic invertebrates as well as planktonic invertebrates as it sometimes hangs suspended and motionless

just above coral and rocky reefs.

Common Species: Blue Emperor Lethrinus nebulosus

Family: Lutjanidae Snappers

Medium to large perchlike fishes, continuous D fin, forked or emarginate

tail.

Ecology: Most species are predators of crustaceans and fishes but some are

planktivores, sometimes found in medium to large shoals.

Common species:

Green jobfish Aprion virescens (1.1m, elongate, forked tail

deper than body)

Twinspot snapper Lutjanus bohar (75 – 90cm, reddish, two dorsal spots in

Juveniles) Bluebanded snapper Lutjanus kasmira (35cm, yellow with 4 black

edged blue stripes)

Russell’s snapper Lutjanus russelli (40cm, yellow, reddish head, black spot under soft dorsal fin)

Humpback snapper Lutjanus gibbus (50cm, deep with steep

forehead,dark caudal fin)

Family: Coracinidae Galjoen



Compressed robust fish with very small tough scales. First dorsal fin

section very spiny (10 spines) and second section of soft dorsal rays tapering backward. Middle to large size, 80cm.

Ecology:

Found in turbulent waters offshore from rocky coasts.. Omnivorous

Common Species: Galjoen Dichistius capensis (West and south coast)

Banded Galjoen Dichistius multifasciatus (east coast)

Family: Cirrhitidae

Hawkfishes

Small grouper-like fish with a tuft of cirri at the tip of D fin spines.

Ecology: Typically perch on edges of coral heads and other Outcrops, feeds on

benthic crustaceans and fishes during the day.

Common species: Arc-eye hawkfish Paracirrhites arcatus (14cm, square blue markings

behind gills) Freckled hawkfish Paracirrhites forsteri (22cm, red spots on face)

Spotted hawkfish Cirrhitichthys oxycephalus (9.5cm, reddish blotches all over body)

Family: Cheilodactylidae

Fingerfins

Middle sized robust fish with finger-like pectoral fin rays some of which

extend far back towards the tail. But not beyond the anus. Five bluish-white spots spaced in line along the flanks. Deeply forked tailfin. Small

mouth with very fleshy lips.

Ecology: Endemic around Southern African coastline where it feeds on small

invertebrates in rock pools, gullies and around reefs.



Common Species:

Twotone fingerfin Chirodactylus brachydactylus (Brown upper

and pale undersides)

Natal fingerfin Chirodactylus jessicalenorum (Red with dark patch behind pectoral fin)

Family: Chaetodontidae Butterflyfishes

Small, colorful, disc-like compressed fishes with small protractile mouths

terminally positioned. Dorsal rays and anal fins similar and continuous,

extending towards tail.

Ecology: Herbivores, omnivores and carnivores. Some are specialist feeders e.g.

coral polyps. Many have territorial home ranges, some may mate for life.

Common species:

Threadfin butterflyfish Chaetodon auriga (Perpendicular chevron lines, spot on dorsal rays, feeds on small reef

invertebrates) Gorgeous gussy C. guttatissimus (Black spots in straight lines,

vertical eye stripe, feeds on small invertebrates) Blackedged b. fish C. dolosus (Fine straight lined spots, anterior

edge black)

Racoon butterflyfish C. lunula (Racoon mask, black eye spot on tail,feeds on small invertebrates and seaweeds)

Pearly butterflyfish C. madagascariensis (Grey-white with orange

bands on rear and tail. Chevron lines, eyestripe and spot on forehead, eats invertebrates and

seaweeds) Double sash b.fish C. marleyi (Two broad coppery v. lines, spot on

top of 2nd sash, eats invertebrates and seaweeds)

Maypole butterflyfish C. meyeri (Semicircle loops on body, feeds almost exclusively on coral polyps)

Limespot b. fish C.unimaculatus (Eyestripe and anterior stripe, large teardrop spot midbody to dorsal, eats small

invertebrates)



Longnose b. fish Forcipiger longirostris (triangular face mask

and elongate snout/mouth with ability to probe holes and crevices for small invertebrates )

Coachman Heniochus diphreutes (Long whip D. filament extending past tail, feeds on small invertebrates

and juveniles often remove parasites from other fish)

Family: Carangidae Kingfish

Medium to large compressed silvery fishes with deeply forked tails and narrow caudal peduncle with reinforcing bony scutes.

Ecology: Mostly pelagic, fast predators of small fish above reefs, mostly on east

coast. Will also take invertebrates on reefs. Occurs in schools.

Common species: Yellowspotted kingfish Carangoides fulvoguttatus (Very large, black

blotch on gill cover)

Blue kingfish Carangoides ferdau (70cm, faded dark vertical bands)

Giant kingfish Caranx ignoblis (1.7m, dark with steeply sloping

forehead)

Bluefin kingfish Caranx melampygus (1m, blue fins)

Bigeye kingfish Caranx sexfasciatus (94cm, white tip on 2nd Dorsal

fin)

Family: Caesionidae

Fusilliers

Smalish, elongate, small oblique mouth, deeply forked tail, continuous D fin.

Ecology:



Fast swimming midwater planktivores sometimes mixed in school during

day.

Common species: Yellowback fusilier Caesio xanthonota (30cm, Dorsal side yellow,

ventral side blue)

Blue and gold fusilier Caesio caerulaurea (28cm, Bright gold stripe,

above eye to tail)

Yellow lined fusilier Caesio varilineata (25cm, 6 yellow stripes, tips of caudal fin black)

Suborder Labroidei

Family: Scaridae Parrotfishes

Medium to large wrasse-like fishes, mouth terminal, teeth fused into

plate-like beak.

Ecology: All are herbivores, most feed on algal film growing on coral rock, some

eat leafy algae or living coral. Rock or coral are crushed to sand to aid in digestion. Parrotfish’s sandy excretion contributes significantly to the fine

structure of beach sand

Common species:

Ember parrotfish Scarus rubroviolaceus (70cm, male pastel blue with darker blue lines around mouth, female pinkish under-

side and dark upper) Blue humphead Chlorurus cyanescens (34cm, distinct hump on head,

blue head and green body, tail blue)



Suborder Blennioidei

Family: Clinidae

Klipfish

Hand-sized to medium, mostly elongate small fish with dorsal fin stretching the length of the body, variable in colour depending on

habitat..

Ecology:

Feeds on small invertebrates in rock pools. Females do not lay eggs but are internally fertilized in order to give birth to well developed juveniles.

Common Species:

Super Klipfish Clinus superciliosus (Dark green to red mottling)

Nosestripe klipfish Muraenoclinus dorsalis (eel-like dark, white dorsal stripe)

Grass klipfish Pavoclinus graminis (Elongate mottled, associated with seaweeds)

Family: Blenniidae Blennies

Small elongate, without scales, long continuous D. fin. Mouth mostly

inferior.

Ecology: Fangblennies are carnivorous and comb-tooth blennies are herbivores,

mostly bottom dwelling or perching on rocks or coral but the twostripe

and piano blennies below are free-swimming.

Common species: Twostripe blennie Plagiotremus rhinorhynchos (12cm, orange with 2

lateral blue lines) Piano blennie P. tapeinosoma (14cm, blue, black and yellow with

piano key pattern on lateral line) Zebra blennie Cirripectes quagga(10cm, dark squiggly bars on light

body) Maned blennie Scartella emarginata (10cm, Brown with vertical

bands and dark spots, mane-like row of tentacles on head)



Suborder Gobioidei Family: Microdesmidae Dartfishes

Small elongate fish with oblique mouths, one or two dorsal fins. Anal and opposite dorsal fins are similarly continuous.

Ecology:

Live in holes or burrows and hover in the water close to the bottom to feed on zooplankton.

Common species:

Fire goby Nemateleotris magnifica (7cm, reddish back halve, 1st D.fin

with bright yellow spike)

Scissortail Ptereleotris evides (l4cm, anterior light blue, posterior dark blue with scissor in caudal fin)

Family: Gobiidae Gobies

Small elongate fish with blunt heads and large mouths. Tails mostly

spatulate.

Ecology:

Mostly cryptic bottom dwelling carnivores of small invertebrates but also hoverers that feed on plankton. Prawn gobies live symbiotically with blind

prawns.

Common species:

Gorgeous Prawn goby Amblyeleotris wheeleri (8cm, light yellow with 6 red bands around body with freckles)

Beautiful prawn goby Amblyeleotris aurora (9cm, three large pink

bands, no freckles, peculiar red spots on caudal fin)



Suborder Acanthuroidei

Family: Siganidae Rabbitfish

Medium sized, compressed oval fish with very small mouth and 14 sharp

dorsal fin-spines (covered with poisonous mucous) of which the first one stands loose from the rest. The single dorsal fin ends in a small set of

about 10 soft rays. Caudal peduncle relatively thin and the small tailfin is truncated. Sometimes spots can be discerned on the body but they

disappear if the fish is stressed. Face looks like a rabbit. Ecology:

Herbivorous, browsing on filaments of seaweeds and eelgrasses on the

south and east coasts.

Common Species: Whitespotted rabitfish Siganus sutor

Family: Ephippidae Batfish/Spadefish

Highly compressed deep bodied fishes with small terminal mouth, nearly

disclike.

Ecology: Feeds on algae and small invertebrates.

Common species:

Orbicular batfish Platax orbicularis (30 – 50cm, Two dark bars vertical

across body)

Family: Acanthuridae

Surgeonfishes and unicornfishes

Disc-like to oval compressed fish with continuous D.fin. One or more pairs of retractable sharp blades at base of tail.



Ecology:

Mostly herbivores or planktivores, feeding by day.

Common species: Pencilled surgeon Acanthurus dussumieri (54cm, rosy body,

yellow dorsal & anal fin blue, tail fin and yellow horizontal eye stripe)

Powder-blue surgeon Acanthurus leucosternon (54cm, black face

powder blue body)

Bluebanded surgeon Acanthurus lineatus (38cm, Upper body yellow with horizontal black edged blue stripes)

Spotted unicornfish Naso brevirostris (60cm, single horizontal horn

on forehead)

Orange spine unicorn Naso lituratus (40cm, Olive brown, semicircle

Yellow cheek stripe runs from eye to mouth)

Family: Zanclidae Moorish idol

Looks like a butterflyfish (Coachmanlike) but is closer related to

surgeonfishes however, its snout is longer and it has no blades in the tail base.

Ecology:

Usually in small groups rarely in large schools, feed on sponges.

Common species: Moorish idol Zanclus cornutus (22cm)

Suborder Sphyraenoidei

Family: Sphyraenidae

Barracudas



Very large 1.5m, elongate cylindrical silvery fish with about 20 darker

bars across the body two small dorsal fins set far apart and mirrors the pelvic and anal fins..

Ecology:

Predator on fish often found in small shoals around reefs.

Common Species:

Pickhandle barracuda Sphyraena jello

Case study: Chaetodontidae Their teeth are brushlike hence the name Chaetodon - meaning hair-like teeth

Diet

The diversity of the butterfly fishes is apparent when the range of their

diet is studied.

Planktivores gather in large schools high in the water and feed on

plankton. Coralivores specialize in feeding on coral polyps and are very territorial.

Generalists feed on a variety of small invertebrates, fish eggs and filamentous algae.

Adult fish tend to be herbivorous while juveniles will peck parasites from

other fish. Juveniles have also been observed cleaning wounds on fish. Coral produces large quantities of mucus when large quantities of sand

are deposited on the coral or the coral is damaged by parrotfish. The chaetodons will eat this mucus, which is rich in fats.

Distribution

From Mossel Bay on the southcoast north to the east-coast of Africa to the Red Sea and the Barrier Reef.

Reproduction and Development

The larval stage is lengthy, from two weeks up to two months.



Adult Chaetodontidae occur in heterosexual pairs, which mate for long

periods or for life while juveniles are often solitary. Colouring in this specie is spectacular and used for mating and

recognition.

Camouflage

The Chaetodontidae have dark bars through the eyes which hide the vital

areas from predators. Many have a false eyespot on the rear section to distract the predators from the real eye.

Survival Strategy.

The Butterflyfish are compressed and flit easily in and out of the cracks

and crevices of the reef. They are mostly diurnal and hide in the reef at night when the larger predators are about. The diversity of the species,

about 120 of them who live mostly in the Indo –Pacific. About 24 live off the coast of South Africa. The high diversity within the species enables

them to avoid intraspecific competition for food.

The false eyespots are also a form of survival strategy. Although they tend to live solitarily or in pairs, chaetodontidae will group

together to exploit food sources, which may be protected by larger fish.

Competition for Space

The competition for space increases with the variety of fish and organisms

living on a reef. The Islands of the Indian Ocean are home to

approximately 800-900 fish species. The Chaetodons and other fish must share the resources available to enable them to successfully co-habit. The

use of space during the day provides hiding places for nocturnal fish and organisms and these are in turn used by diurnal fish during the night. The

specialization of exploiting food has become an art form with the Chaetodons. They also inhabit a large range of habitats, juveniles will

inhabit lagoons and tidal pools. From the lagoon coral band to shallow coral and rocky reefs to ramified coral bands and the outer slopes of the

reef to the water column chaetodons will utilize diverse habitats and thereby increase the diversity of foods and shelter they can make use of.

Therefore by different types of butterfly fish using different strata of

habitat and specializing in their own particular diet they reduce the competition among the Chaetodontidae. Where different species of



butterfly fish occur in the same vicinity, they often co-exist because they

focus on different foodstuffs.

Ecological importance Reef and rocky shore ecology is very delicate and sometimes the slightest alteration or external influence may threaten whole communities that

exist on reefs and in rock pools. A fine balance exists between fish and other reef or rock pool inhabitants.

Clownfish, for example prevent being preyed upon by lurking in the

tentacles of anemones. They have developed a mucous layer covering their whole bodies, which do not trigger the dreaded stinging nettles of

the anemone. The anemone tentacles will however have detrimental effects on clownfish predators who come too close.

Nose-stripe clownfish within the tentacles of a giant anemone

Other fish have the ability to hide away in coral or rock fissures or to form a clever alliance with another species that feeds on its hunter. An

example is the rock lobster, eel and octopus love triangle. Octopus loves

rock lobster. Eels love octopus. Thus you often find rock lobster hiding in a fissure with an attendant eel. The lobster attracts the octopus, the eel

nabs the octopus and the lobster can plan a family due to the protection afforded by the eel.

These are just a few simple examples of the dynamics on an ocean

reef. In much the same way the predators have adapted their abilities in order to overcome the difficulty of obtaining food.

Potato bass for instance are beyond irritation with food fish constantly

hiding in fissures and cracks and have consequently acquired the ability to suck fish from their place of hiding by suddenly opening their mouth’s and

creating a void which sucks in the water and the fish in the immediate



area in front. It certainly beats having to chew through the rock. In

answer to this method of obtaining food, triggerfish have the ability to “lock” their dorsal and pelvic spines in place which makes it virtually

impossible to remove them from a fissure or hole.

Angler fish are not fast swimmers or streamlined but they are well

camouflaged and uses a lure on their heads to attract smaller fish which it

catches and devours with its huge mouth. In fact their action of

capturing a fish is considered one of the fastest actions in nature. So, if

you see a funny fish out there don’t just roll over and laugh, it took

millions of years for its mother to dress it funny and it is probably

considering your protein content.

DRESSED TO KILL

Most predators are dressed to kill in their own specific way. If speed is

important to catch your prey it is important to look like a Ferrari and to have a powerful engine. This means, in marine terms, a slender,

streamlined body and a rigid and powerful pair of fins to propel you. If stealth is your vice then it is important to look inconspicuous. This can be

achieved by adopting the appearance of your environment. In this way your

prey will pretty much sidle up to you without noticing your presence. A

stonefish will look way out of place

on a smooth, brightly coloured coral bed. Thus settling on a rough rock face

or debris will make the stonefish virtually invisible. The only drawback for a stonefish is when the rock face

clears its throat politely and categorically states that it was there first.

rocky shore & coral reef fishes · 2013-08-26 · the objective of this component is to...

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