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11 THE FISH Introduction Ninety species of fish have been recorded in the Reserve (table 2). These are contained in 14 orders and 48 families. The largest order, the perciform or perch-like fishes consists of 60 species, 66% of the total number of fish. The largest families are the Tripterygiidae and Labridae, the former with 13 species and the latter with 7 species occurring in the Reserve. A few families, the Gobieosocidae, Gadidae, Syngnathidae, Serranidae, Carangidae, Kyphosidae and Pomacentridae contain between 3 and 5 species; however, the majority are represented by 1 or 2 species only. The most abundant fish in the Reserve are the small benthic tripterygiids, Forsterygion varium, Notoclinops segmentation and Gilloblennius tripennis; the midwater plankitvore, (bigeyes) and the goatfish, Upeneichthys porosus. in descending order of abundance, are: Pempheris adspersa The other common fish, sweep (Scorpis aequipinnis) , paketi (Pseudolabrus celidotus) , snapper (Chrysophrys auratus), leatherjackets (Parika scaber), blue maomao (Scorpis violaceus) , hiwihiwi (Chironemus marmoratus), red moki (Cheilodactylus spectabilis) , parore (Girella tricuspidata), blue cod (Parapercis colias) and banded wrasse (Pseudolabrus fucicola) . Notes on classification and naming The fishes of the world are separated into three major divisions or classes: lampreys; The jawless fishes, class Agnatha, including the hagfish and the cartilaginous fishes, class Chondrichthys and the bony fishes, class Osteichthys. Reserve. Only the Agnatha are not represented in the Within these divisions fish with similar anatomical characteristics are classified into orders ( -formes endings), which are then further divided into suborders and families ( -idae endings). The arrangement of orders and families used here follows those used by Midgalski & Fichter (1976) for the cartilaginous fishes and Greenwood et al. (1966) for the bony fishes. 12 Each species is then given a scientific name consisting of two parts. The first designates the genus to which the fish belongs. with the same genus name have certain features in common. the species name distinguishes one species from any other. Fish The second, The scientific name is important as many species have assorted common names which usually vary depending on the locality in which they were found. For example, the banded wrasse, Pseudolabrus fucioola is also known as the chinaman or kelpfish in other parts of New Zealand and as the„purple wrasse in Australia. The common name 1kelpfish1 can also refer to other species such as Chironemus marmoratus (hiwihiwi) and Odax pullus (butterfish). Since several species.have been described more than once and under different names in the past, the author of the correct name, or the scientific name currently in use, is often indicated. Thus the 1 authority1 appears directly after the species name, unpunctuated if it retains the original genus and bracketed if the fish was originally described in another genus. Many fish in New Zealand are only relatively recent discoveries and have yet to be officially described. Usually these are nominally assigned to a genus but are given no species name, e.g. the lizardfish, Synodus sp. Where there are several undescribed species all belonging to the same genus the different species are distinguished by numbers or letters of the alphabet, e.g. the undescribed tripterygiids are listed here as Forsterygion sp. A.to F.sp.F . When listing several species of the same genus, or when mentioning the same species several times it is common practice to abbreviate the genus name to the first one or two letters. Several structural characters are used : to classify fish into their various groupings. Neccessarily these are constant within a species but vary between species. They include the number, positioning and shape of the fins; the number of spiny and soft rays supporting each fin; the number and shape of the lateral line(s); the number of pored lateral line scales; the presence or absence of scales, their arrangements and the types of scales found on various parts of the fish's body; variations in the structure of skeletal components such as the jaws, vertebrae, gill arches and opercula; the number, structure and positioning of the teeth and gill rakers and the possession of species appendages such as sensory feelers and protective spines. 13 Format DESCRIPTIONS: Each fish is introduced by its scientific name and accepted New Zealand common names. The scientific name, especially the species name is often selected to indicate some peculiarity of the structure, habit or habitat of .the fish designated. Its derivation is indicated where it is known. The general appearance, body shape and colour is described for each fish. Other distinguishing features such as the number, structure, positioning, shape and size of the fins; the relative sizes of the head, mouth and eyes and the presence of any special protective or sensory structures are also described. Detils of size are usually given as the maximum length recorded for the species and the average size range which would be observed if diving in north eastern New Zealand coastal waters. All length measurements refer to the total length of the fish, i.e. the distance from the tip of the snout to the tip of the tail. or metres. Lengths are presented in millimetres Average or maximum weights are also given as a measure of size where the information is available. These are indicated in grams or kilograms. Each fish is illustrated with a black and white line drawing. The maximum size and a scale are also presented, the scale being adjusted to the average size of the fish. Along with the illustration the fin formula (the characteristic number of spines and rays in each fin) and the number of pored lateral line scales are presented for each fish where known. The notation used can be explained using the goatfish as an example: D.viii. i.8; A.ii.6; represent the fins: C = caudal. V.i.5; P.15-16; C.15; L.l. 28-30. The letters D = dorsal, A = anal, V = ventral, P = pectoral, Roman numerals are used to indicate the number of spines and arabic numerals to indicate the number of soft rays in each fin. L.l. refers to the number of lateral line scales. Therefore, goatfish have two dorsal fins, the first composed of 8 spines and the second of 1 spine and 8 soft rays. ventral fin The anal fin consists of 2 spines and 6 rays. Each has one spinous and five soft rays and each pelvic fin has 15 or 16 rays. The caudal fin is supported by 15 rays and the number of pored scales forming the lateral line may vary between 28 and 30. 14 Various aspects of the mode of life and behaviour of each species can aid in field identification. Thus, the characteristic activity period of each fish (i.e. whether the fish is active at night or day) and the typical mode of locomotion are described. An indication of where the fish are most likely to be found and their social organisation is also given, i.e. whether the fish are most likely to be found at the water surface, in midwater, close to the bottom or resting on the bottom and whether they form schools, aggregations or are solitary. the size of the group and whether Information is provided on the fish range widely over the reef or are site attached with a more restricted movement range. DISTRIBUTION: The distribution of each species is described in a series of progressively narrowing scales. Firstly distribution is described in general as to where the species has been recorded in the world, and then where it is found around New Zealand. An indication of the relative abundances around the New Zealand coast are given where possible. All New Zealand place names referred to in the text are indicated in figure 1. Local distribution patterns describe where the fish is found in the Reserve. Again abundances are also indicated. For many of the reef associated species estimates of the numbers of fish found in the different subtidal habitat types are available. These were obtained by counting fish along five transect lines in each habitat. p Moderate to large fish were counted in 50 x 10m transects, whereas 25 x 4m transects were used for the smaller benthic species. The numbers of each species in a habitat were averaged to obtain an estimate of the density present. These densities are expressed here as the average number of fish per hectare. The distribution and abundance patterns around New Zealand and within the Reserve are illustrated. Seasonal differences are indicated where appropriate by a dashed line. FEEDING: The diet and foraging habits of each fish are briefly described. Structural adaptations for finding, catching and consuming prey are also noted. These include sensory feelers, lures and the structure of the teeth and jaws. A more detailed composition of the diet is diagrammatically represented. This information was obtained mainly from fish taken from 15 from the Reserve and adjacent coastal waters. Samples of fish which are rare in the Reserve were obtained form the Poor Knights Islands. LIFE HISTORY: Several aspects of the life cycle are considered: (i) Age and growth - the maximum age recorded for a particular species is given along with an indication of their growth rate. The latter is best illustrated by the size reached at the end of the first year after settlement and/or the size and age at which the fish reach maturity. This allows for comparisons of growth rates between species and between different populations of the same species. (ii) Reproduction - the timing of the breeding season, the mode of reproduction and spawning behaviour are described where these are known. The occurrence of parental care is also noted. Where spawning observations are lacking the breeding season is estimated by the presence of ripe gonads, observations of courting behaviour, the presence of eggs and the timing of juvenile settlement. (iii) Eggs and development - the eggs are described with respect to size, structure and whether they are demersal or pelagic. Notes on embryonic and larval development are provided where these are available. (iv) Juvenile settlement - the recruitment period, the size of newly settles juveniles and the habitats in which they are found are described. Any differences from adult fish in colour, structure, behaviour or distribution are also discussed. • The seasonal aspects of breeding, presence of eggs in the plankton and juvenile settlement are illustrated. Question marks are used to indicate that the extent of the breeding season is uncertain. 16 Table 2: A list of the fish species recorded in the Cape Rodney to Okakari Point Marine Reserve. The scientific name, authority and accepted common names of each fish are presented along with and indication of relative abundances and the quality of information available for each species. KEY Relative abundance Field guide • abundant >10 individuals or >2 schools on all dives O common 5-10 individuals or O frequent 1-5 individuals or 1-2 schools on most dives v occasional 1-5 individuals or 1-2 schools on some dives R rare s seasonally present 2 schools on most dives only a few sightings ever recorded Quality of information available *** good local knowledge - detailed studies in the Reserve or north east New Zealand ** good New Zealand knowledge or preliminary local knowledge * ' little New Zealand knowledge, some information from studies elsewhere in the world - . little information available Abbreviations B & S = Bloch & Schneider C & V = Cuvier & Valenciennes M & P = McCulloch & Phillips Class Chondrichthys Subclass Elasmobranchii ORDER: Squaliformes Family Carcharhinidae Carcharinus hrachyurus (Gunther) bronze whaler shark R - Family Sphyrnidae Sphyrna zygaena (Linnaeus) hammerhead shark R - 17 Family Isuridae Isurus oxyrinchus Rafinesque ORDER: mako shark Rajiformes Family Dasyatidae Dasyatis brevieaudatus (Hutton) short-tail stingray Dasyatis theditis (Waite) long-tail stingray Family Myliobatidae Myliobatis tenuicaudatus (Hector) eagle ray Family Torpedinidae Torpedo fairohildi (Hutton) electric ray Class Osteichthys Subclass Actinopterygii Superorder Teleostei ORDER: Anguillliformes Suborder Anguilloidei Family Muraenidae Gymnothorax prasinus (Richardson) yellow moray eel Family Congridae Conger wilsoni (B & S) conger eel Family Ophichthidae Ophisurus serpens (Linnaeus) ORDER: snake eel Clupeiformes Family Clupeidae Sccrdinops neopilohardus (Steindacher) pilchard Family Engraulidae Engraulis australis (White) ORDER: anchovy S almoni formes Suborder Myctophoidei Family Synodontidae Synodus sp. ORDER: lizardfish Gobieosociformes Family Gobieosocidae Diplocrepis puniceus (Richardson) suckerfish 18 Tracheloschismus pinnulatus (B & S) lumpfish Tracheloschismus melobesia(Phillips) barred clingfish ORDER: dellichthys morelandi Briggs painted clingfish Gastrocyathus gracilis Briggs slender clingfish Gadiformes Suborder Gadoidei Family Gadidae Physiculus bacjius (B & S) red cod Physiculus breviusculus(Richardson) bastard red cod Lotella rhacinus (Richardson) ORDER: rock cod Antheriniformes Suborder Exocoetoidei Family Exocoetidae Eeporhampus ihi(Phillips) ORDER: piper Berycifoi Suborder Berycoidei Family Trachichthidae Hoplosthethus elongatus(Gunther) slender roughy Family Berycidae Trachichthodes affinis(Gunther) ORDER: golden snapper Zeifoi Family Zeidae Zeus faber Linnaeus ORDER: john dory Gasterosteiformes Suborder Syngnathoidei Family Syngnathidae Lissocampus filum (Gunther) short-snouted pipefish Stigmatopora macropterygia Dumeril long-snouted pipefish Hippocampus abdominalis(Lesson) ORDER: seahorse Scorpaenifoi Suborder Scorpaenoidei N Family Scorpaenidae Scorpaena cardinalis Richardson red scorpio.nfish 19 Family Trigilidae red gurnard Chelodonichthys kumu (Lesson) ORDER: Percifc Suborder Percoidei Family Serranidae Ellerkeldia huntii (Hector) redbanded perch v ** Caesioperca lepidoptera (B&S) butterfly perch O * R - Caprodon longimanus (Gunther) splendid perch Callanthias allporti Gunther Family Acanthoclinidae Acanthoclinus quadridactylus (B&S) rockfish Family Carangidae Seriola grandis Castlenau kingfish Caranx geovgianus Cuvier trevally O * s O ** s Decapterus koheru (Hector) koheru # Trachurus novaezelandiae Richardson Family. (B&S) snapper • *** goatfish • ** bigeye • *** (B&S) Mullidae Pempheridae Pempheris adspersa Griffin Family Kyphosidae Girella tricuspidata (Qiioy & Gaimard) parore • ** V - Kyphosus sydneyanus (Gunther) Family * * kahawai Upeneichthys porosus (C & v) Family m * Sparidae Chrysophrys auratus Family horse mackerel s Arripidae Arripis trutta Family • ** Scorpis aequipinnis Richardson sweep • **,* Scorpis violaceus (Hutton) blue maomao • *** R - Pentacerotidae Paristiopterus labiosus (Gunther) giant boarfish Zanclistius elevatus (Ramsay & Ogi'lby) long-finned boarfish R Family Family Pomacentridae Parma alboscapularis black angelfish R - Chromis dispilus Griffin two-spot demoiselle o *** Chromis hypsilepis(Guenther) single-spot demoiselle R - hiwihiwi • Chironemidae Chironemus marmoratus (Gunther) 20 Family Aplodactylidae Aplodactylus meandratus Richardson marblefish v # ** Family Cheilodactylidae Cheilodactylus spectabilis Hutton red moki Cheilodactylus douglasi porae v ** Cheilodactylus macropterus(B & S) tarakihi R ** blue moki R * yellow-eyed mullet v ** Pseudolabrus oelidotus (B & s) paketi • *** Pseudolabrus fucicola (Richardson) banded wrasse O *** • ** Pseudolabrus miles (B & s) scarlet wrasse Family Latridae Latridopsis ciliaris (B & S) Suborder Mugiloidei Family Mugilidae Aldrichetta forsteri(c & v) Suborder Labroidei Family Labridae Pseudolabrus inscriptus(Richardson) green wrasse v ** Pseudolabrus luculentus (Richardson) orange wrasse v ** Bodiccnus occycephalus (Bleeker) red pigfish v ** Coris sandageri (Hector) Sandager1s wrasse v ** butterfish o ** blue cod O ** spotted stargazer R - crested blenny O ** Family Odacidae Odax pullus Suborder Trachinoidei Family Mugiloididae Parapercis colias (B & s) Family Ura'noscopidae Genyagnus monopterygius (B & S) Suborder Blennioidei Family Blenniidae Blennius laticlavius Griffin mimic blenny Plagiotrerrrus tapeinosoma (Bleeker) R * • *** Family Tripterygiidae Forsterygion varium(B & S) mottled blenny Forsterygion capito (Jenyns) cobble blenny m *** 21 Forsterygion sp.B yellow-black blenny v ** Forsterygion sp.C oblique-swimming blenny v 8 Forsterygion sp.D Yaldwyn s blenny v ** Forsterygion sp.E scaly-headed blenny v ** Forsterygion sp.F chocolate blenny v ** Gillohlennius tripennis spectacled blenny • ** Gillohlennius deoemdigitatus threepenny • v ** Eelcogramma sp.A chequered blenny V ** Eelcogramma sp.B tiger blenny V ** Notoclinops segmentation (M & P) banded blenny v ** red topknot v ** Ericentrus ruber{Button) commmon weedfish V * Cristiceps aurantiacus crested weedfish hlotoclinus compressus (B & S) Family Clinidae Suborder Scombroidei Family Gempylidae Thrysites atun(Euphrasen) snoek R * Family Scombridae Scomber australasicus ORDER: common mackerel Tetradontifoi Suborder Balistoidei Family Monacanthidae Parika scaber(B & S) leatherjacket • *** porcupinefish V - sunfish R * Suborder Tetradontoidei Family Diodontidae Allomycterus whitleyi Phillips Family Molidae Mo la mo la Linnaeus 22 CLASS CHONDRICHTHYS the cartilaginous fishes The fish belonging to this group, the sharks, skates, rays and chimaeras, exhibit many similarities in their general body structure. There is no true bone, the skeleton being composed entirely of cartilage. These fish lack typical scales. Instead, the skin is covered with tooth-like dermal denticles, closely set to form a sandpaper-like surface known as shagreen, which is extremely tough and difficult to penetrate. They do not possess gill covers. With few open out on each side of the body. exceptions five gill slits Most species have a spiracle near each eye, through which they can 'breathe' while feeding or, as in the case of the rays, when the mouth which is situated on the undersurface is covered in sand or mud. All these fish have a well developed lower jaw with numerous teeth arranged in several series. nictating membrane, or third eyelid, is present. when present, are rigid In some groups a Dorsal fin spines, and not erectile. Swim bladders are not found in this group of fishes. This class contains about 550 present day species. characters illustrated). 23 ORDER SQUALIFORMES - the sharks In all there are about 225-250 species of sharks. They are predominantly marine fishes, although a few species run far upstream into brackish and freshwater. Most occur in the tropical and subtropical belt, but some species are found in temperate and even polar waters. Sharks usually dwell in shallow waters; however a few species prefer depths of several hundred metres 0 Sharks are typically cylindrical in form. Most are large, powerful and fast swimming; however, some species are extremely sluggish and rarely move. Size varies from 15-20m for the whale sharks down to about 0.5m for the smallest shark species„ Without exception sharks are carnivorous, feeding primarily on smaller fish. Fast swimming sharks pursue and catch their prey. species lie in wait for passing fish. The more sluggish These predaceous species have large sharp teeth adapted for tearing and cutting. Some of the smaller sharks, which feed mainly on hard-shelled crustacea, have pavement-like crushing teeth. The teeth are not fixed into sockets like most fish, but are attached to a band which is continually growing forwards. The teeth at the rear are in a recumbent position, moving forward and becoming upright and functional as those in the front are shed. Reproduction in the sharks takes place through internal fertilisation. The males possess a pair of copulatory organs, the claspers, which are located on the inner edges of the pelvic fins. transfer sperm to the female. The claspers are used to In most sharks development is ovoviviparous, but in some species is oviparous or viviparous. Compared with the teleost fishes the number of young produced by sharks is small. Three families of sharks are represented, each by one species, in the Reserve. Family Carcharhinidae - requiem sharks This is the largest shark family. temperate seas throughout the world. Its members inhabit tropical and Their chief cahracteristig:s are: There are two dorsal fins, the second of which is smaller and is situated directly opposite the anal fin; the upper lobe of the tail fin is sickle-shaped and 2-3 times larger than the lower lobe; the eyes possess a nictating membrane; the spiracles are either much reduced in size or are lacking; the teeth are 24 triangular and razor sharp. These sharks are usually coloured drab brown or grey. The majority of species are harmless. Family Sphyrnidae - hammerhead sharks The hammerhead sharks are easily distinguished from all other sharks by the flattened head which is extended into hammer-like lobes on each side. These swift swimming sharks occur in shallow, warm seas with some species wandering into cooler regions as seas warm over the summer. Family Isuridae - mackerel sharks These are medium to large, surface swimming sharks found in most seas of the world. Their bodies are torpedo-shaped and stoutly built, tapering to a slender, depressed caudal peduncle which usually has a strong keel on each side. This lateral keel extends onto a large lunate tail fin. first dorsal fin is large. anal fin. The The second is small and is situated opposite the The five gill slits are wide and are located in front of the pectoral fin. 25 Familys Carcharhirtus brachyurus - bronze Carcharhinidae whaler (Carcharhinus = jagged snout brachyurus = short-tailed) DESCRIPTION: This shark is distinguished by its flattened snout, metallic bronze colouration and the characteristic shape of the tail» The first The dorsal fin is large and is situated in front of the ventral fins. pectoral fins are relatively large» and blade-like» The mouth is large and the teeth small There are five gill slits, the last of which is situated above the base of the pectoral fin. Small spiracles are present» These fish grow to about 4m in length; however those sighted in the Reserve are much smaller/ the largest being recorded at 2„75m. Despite their large size, these sharks are generally shy. Only one unprovoked attack on man, by a bronze whaler, has been officially reported. DISTRIBUTION s Generals C. brachyurus is found around Australia and in New Zealand waters as far south as Cook Strait. In New Zealand the bronze whaler is only commonly seen during the summer when they appear to move into shallower water, even entering the breaker zone of surf beaches. FEEDING: This species is an opportunistic predator, its food consisting mainly of octopus and fish. Little is known of its natural feeding habits. Studies on related species have indicated that members of this genus feed on healthy, free-moving animals and feeding is not limited to scavenging on the dead and dying. Observations made, in the Reserve, of feeding on speared fish have shown that the bronze whaler is similar to other sharks in detection and taking of food. Initial attraction appeared to be in response to the vibrations set up in the water by the struggling fisho approached the bait eating. Usually, the shark slowly and would 'sniff1 at it several times before • Sometimes it would attack the fish with a fast rush and take it immediately. The prey was bitten and ripped apart with a sideways shaking of the head. LIFE HISTORY: Little is known of the life history of these sharks. Like the other members of its family, this species is viviparous, i.e. the young are born alive. 27 Family: Isyrus ox^rmelhys - mako, Isuridae blue pointer (Isurus = equal-tailed) DESCRIPTIONS This sreamlined, active shark is blue or blue-grey above and white underneath= The two colours are sharply separated„ The body is torpedo-shaped, with a pointed snout and a slender tail stalk which is flattened from above and below„ the tail stalk* There is a strong keel on either side of The first of the two dorsal fins is large and the second is small and situated opposite a similar sized anal fin* Mako sharks can grow to lengths of 4o5m and weigh as much as 485kg= The largest caught on rod and reel was taken off Mayor Island, New Zealand, and weighed 482.5kg„ These are wide-ranging, solitary sharks usually found in surface waters. They are not generally regarded as being dangerous to man, DISTRIBUTIONS Generals Zealand seas. The mako occurs in Australian, South African and New It is found around the entire New Zealand coastline but is most common north of Cook Strait. Locals These fish are infrequent visitors to shallow coastal waters and have only occasionally been reported in the.Reserve„ FEEDINGs Io oxyrinchus is a voracious carnivore, feeding mainly on small schooling fishes» The teeth are small and awl-like and are well adapted for seizing prey. LIFE HISTORYs Little information is available on age, growth and reproduction in this species» have grown to about 2m long* Sexual maturity is attained when individuals Mew Zealand distribution 29 Family: jiplh^ma zyganea - Sphyrinidae hammerhead shark (Sphyrna = a hammer zygaena = a yoke) DESCRIPTION: The peculiar shape of the head immediately distinguishes this species from other sharks which frequent New Zealand waters . The front portion of the head is flattened and extended into lobes, one on each side. The eyes, situated at the end of each lobe are bluish and possess a brown nictating membrane» There are two dorsal fins. The second, the smaller of the two, is situated opposite the anal fin„ The upper lobe of the tail is distinctly notched and is much longer than the lower lobe* There are five gill slits and the fourth and fifth sit over the base of the pectoral fine The triangular and pointed teeth are serrated in juvenile hammerheads but have a smooth edge in' the adult fish* Colouration ranges from pale grey to a dark brown dorsal surface which fades to pale yellow on the belly. Individuals can grow to 6.5m in length, with the 'hammer8 measuring 2m in. width. Specimens up to 1«, 25m have been observed in the Reserve. These sharks are usually considered dangerous« DISTRIBUTION: General: Sozygaena ranges along the east coast of Australia to Tasmania, the coast of Western Australia and in New Zealand as far south as Cook Strait. It frequents both open oceans and shallow coastal bays. Juveniles often ascend rivers to the end of their tidal influence. Local: rocky reefs. The hammerhead shark is only an occasional visitor to Small individuals have been sighted in the Reserve, usually during the summer months. FEEDING: Members of this species feed predominantly on fish. Mackerel (Scaustralasieus) and other schooling fishes are taken by the younger, more active hammerheads, while cruising in surface waters. The older sharks live mainly on stingrays„ LIFE HISTORY: The life history features of this species are poorly known. The young are born alive. A female about 3m long can produce up to 30 pups. Sphyroa zygaen^ 31 OlRDER RAJFORMIES - rays aod skates This order includes the sawfishes, guitarfishes, electric rays, skates, stingrays, eagle rays and mantas. recognised Members of this group are easily by their body form which is adapted to life on the sea floor. The body is flattened dorso-ventrally and the large pectoral fins are joined to the sides of the head and body,.. The five pairs of gill openings are situated beneath the body disc and not on the sides of the head, as seen in the sharks. The spiracles, placed close behind the head, are very large to enable the ray to 'breathe1 while lying on sand or mud. are situated well back, or may be lacking altogether. The dorsal fins There is no anal fin. In many species the tail is reduced to a whip-like appendage, without a tail fin and often with one or more serrated spines at its base. Species range in size from a few centimetres long to the giant manta rays with a breadth of about 7m and weight of around 1500kg. The Raj iformes are widely distributed fish in both latitude and depth. They occur in the Atlantic, Pacific and Indian oceans. marine They are primarily temperate fish, but several species have colonized freshwater rivers. Most live on or near the bottom. They usually swim slowly, staying close to the bottom, although they are capable of rapid propulsion when neccessary. Movement is usually achieved by undulations of the pectoral fins; however, some species also use the tail and body muscles. Skates and rays eat a variety of foods. Some species prefer the hard-shelled molluscs while others feed mainly on fish. The large mantas feed on planktonic organisms and small fish. In this group reproduction occurs with internal fertilisation. The males possess a pair of claspers along the inner edges of their pelvic fins in the same manner as the sharks. The inner edges of the claspers have grooves with overlapping edges, thus aiding transport of the sperm into the female. Development may be oviparous - the eggs are laid encased in a horny capsule, or ovoviviparous - the embryos develop within the female and are extruded at the larval stage. Three families of this group are represented in the Reserve. 32 Family Dasyatidae - stingrays The stingrays are best known for; their long, whip-like tails which are armed with spines near the base. The body disc is flat and wide. Nearly 100 species of stingrays are distributed in warm shallow seas throughout the world. Stingrays generally lie on the bottom, buried in sand or soft sediment. They are usually mottled grey and brown on the dorsal surface and are pale yellow on the ventral surface. These fish range in size from 0.3m to 2m in breadth. The venomous spines present at the base of the tail can inflict a severe wound. The venom may have a paralyzing effect on humans, but is rarely fatal. Two species of stingray, Dasyatis brevicaudata and D,theditis are found in New Zealand and in the Reserve. Dotheditisr the long-tailed stingray, is distinguished by possessing a much longer tail than the former species. However, little information is available on this species, hence it is not considered here in detail. Family Mlyiiobafadae - eagle rays The eagle rays are more pelagic than the stingrays, although they still feed on the bottom. Unlike the typical bottom-dwe11ing stingrays, members of this group have a distinct head region. The eyes and spiracles are situated on each side rather than on the top of the head. Most species have one or more venomous spines at the base of the tail. Eagle rays occur in warm seas throughout the world. Only one species is known in New Zealand and in the Reserve. Family Torpedioidae - electric rays The body and pectoral fins of these rays form an almost circular disc. The electric rays are characterized by a smooth, scaleless skin and by the presence of two large electric organs, one on each side of the head. They can reach up to 1.5m in length and weigh around 100kg. These fish are poor swimmers and spend most of their time partially buried in sand and mud. Some species live in shallow inshore waters while others are blind and live at great depths. Only one species occurs in the Reserve. 33 Family: Das^atis bre^gcaydafos - short-tailed Dasyatidae stingray (brevicaudatus = short-tailed) DESCRIPTION: The disc in this species is almost quadrangular. is long and whip-like and is-fairly thick at, the base. The tail This fish was originally described from a mutilated specimen without a tail, hence the species and common names. There are no dorsal or caudal fins. base of the tail there are two serrated spines. Towards the These spines have a groove along which venom is conducted, from the venom glands at the base, to the tip of the spine. Colouration varies fron slate grey to brownish grey on the back and is white on the underside. This is the largest of our. common rays. Short-tailed stingrays caught in New Zealand waters have been recorded at 4.2m long and 2.1m wide. These fish are usually found resting on the substratum. swimmers. They are poor Movement is achieved by undulations of the large pectoral fins. Both fins move in phase. DISTRIBUTIONs Generals This species occurs around Australia and New Zealand. In New Zealand they are found as far south as Otago, but are most common around the North Island. They usually inhabit sandy coastal areas to depths of 100m, but often also venture into harbours and estuaries. Locals Dobrevicaudatus is occasionally found over rocky reefs such as the Reserve. FEEDINGs Any available animal food is taken by these fish. Their diet consists mainly of shellfish and crabs, taken while foraging over open sandy bottoms. LIFE HISTORYs Little information is available on the life history of the short-tailed stingray. Like other members of its family this species is an ovoviviparous breeder. 35 Family: 6¥ifliobatyS feoyocaudatys - Myliobatidae eagle ray, whiptail (tenuicoudatus = slender-tailed) DESCRIPTION: This ray is easily distinguished from the stingrays by the snout which is distinct from the pectoral fins forward of the level of the eyeso The body disc is diamond-shaped and wider than it is long. The tail is long and slender with two venomous spines present at the base. Colour varies in this species from a mottled greenish-grey to almost black. Eagle rays can grow to 1.2m in width. They are solitary fish and are usually seen resting on the bottom or swimming close to the substratum. They swim like the stingrays, by beating the pectoral fins. However, the pectoral fins move in opposite phase whereas the stingrays beat their fins simultaneously. DISTRIBUTION: General? Australia. This species is found in New Zealand and southern In New Zealand, they wander as far south as Otago but are most abundant north of Cook Strait, especially in the Hauraki Gulf where they are frequently seen in shallow waters over the summer. Local: This is the most common ray of the Reserve.' Individuals range over the whole reef and are not found in any particular habitat. FEEDING: Af. tenuicaudatus appears to be restricted to foraging over rocky bottoms. They move slowly over the bottom, wrenching their prey from the rockc Hard-shelled prey are crushed with pavement-like, heavily denticulated teeth plates. Food consists mainly of crabs, gastropods and hermit crabs. Observations on feeding behaviour suggest the eagle ray crushes its prey and expels the shell fragments from its mouth. No shell fragments have been found in the stomach. LIFE HISTORY: The life history features of this species are poorly known. Reproduction is ovoviviparous0 37 Family : Torpedo fairchaldio DESCRIPTION; elect he ray, Torpedinidae torpedo ray Several features distinguish this species from the other rays found in the Reserve» The head and pectoral fins form a distinct disc which is well separated from the thick rounded tail. fin and two dorsal fins „ or greyish-brown o Scales are absent0 There is a caudal Colouration is a mottled grey The torpedo ray can reach up to 1« 2m in length«, This fish is able to deliver an electric shock if touched* There is an electric organ on either side of the head, between the upper and lower surfaces of the skin. These are kidney-shaped groups of hexagonal cells which are filled with a clear jelly-like substance» charge is generated here* The electric The discharge is of sufficient strength to knock out a grown man for an hour or so* The ray is capable of delivering 40-50 consecutive shocks, each one becoming weaker. A period of rest is then required for the fish to recover . Torpedo rays are poor swimmers and are usually encountered buried in sand^ with only their eyes and spiracles protruding,, DISTRIBUTIONi General: This species is found in south-east Australian seas and around New Zealand. They are widely distributed around the entire New Zealand coastline to depths of 200m» Locals Although T.foivohitdi tend to prefer deep waters they are occasionally seen inshore and have been reported in the Reserve at depths of about 14m0 FEEDING^ Small fish are the major prey for this species„ and shrimps are also eaten. Shellfish, crabs Fish are caught by the ray enveloping them from above, with their pectoral fins„ and stunning the prey with an electric shocko LIFE HISTORY: this specieso Little is known of age^ growth .or reproductive habits of Diet This page has intentionally been left blank 40 This class incorporates the vast majority of living fishes, both freshwater and marine. The presence of bone is the major character distinguishing them from the jawless fishes (class Agnatha) and the cartilaginous fishes (class Chondrichthys). The bony fishes can be separated into four divisions . The first three; the lobef ins,, the lungfishes, or coelocanths, and the birchirs are primitive groups of fishes with large numbers of species known from the fossil record, but with few living representatives. The fourth group, the teleosts, includes the majority of present day fishes and consists of about 20,000 species. features: The teleosts are charcterised by the following (1) A well developed, bony vertebral column and skull; (2) which are supported by soft or spiny rays; (3) A single gill cover, or operculum, which covers the cavity containing the gills„ Scales may be present or absent. The general features of a teleost fish. the characters illustrated)0 Fins (No one species exhibits all 41 ©FIDER AMGUILUFORMIES - the eels This is a specialised group of species which have become adapted to living in narrow holes and crevices, slendero The body has become long and The pelvic fins are reduced and a continuous dorsal-anal fin has developed. All fins are spineless * The gill openings have been reduced to small slits on either side of the head and are without gill covers. skin. Scales, when present, are minute and deeply embedded into the The swim bladder retains its primitive condition in these bottom dwellers» Many species are nocturnal and have a well developed sense of smell for tracking prey. The nasal tubes are pronounced and set well apart „ The eels® eyes differ from other fish as the iris is able to contract and expand, thus controlling the amount of light reaching the retina. The eyes are covered with a protective skine Because the eels lack gill cover with which to set up a bellows motion and keep water flowing over the gills, they must always keep their mouths open, forcing water toward the gills with a swallowing motion. These fish achieve their snake-like movement along the bottom by a series of transverse waves travelling the length of the body and increasing in magnitude from nose to tail (anguilliform locomotion) . This order is comprised of 20 families. in New Zealand» Several species are found Few are of any commercial value as most are uncommon and infrequently caught» Only three families are represented in tbe Reserve» Family IMyrasniitiia© - morays These are usually large, powerful eels, some reaching lengths of 3mo They have no pectoral fins, the gill openings are small and the mouth is large with strong, sharp teethe The body is typically flattened - from side to side and the scaleless skin is thick and leathery» fin always begins on the head. The dorsal Individuals are usually brightly coloured» The morays constitute a family of more the 80 species occurring in their greatest abundances in tropical and subtropical waters, with a few species straying into temperate regions. They live in shallow coastal waters and most species are nocturnal» Several species occur in north-eastern New Zealand waters. one, Gymnothovox prasinus, the yellow moray, is common. moray species found in the Reserve. Only This is the only The other species are rare on the coast, but are more abundant in the warmer waters around offshore island groups 42 such as the Poor Knights Islands and the Moko Hinau Islands. These-are: the grey moray, Gymnothorax nubilus; the speckled moray, G. obesus-, the mottled moray. Goprionodon and the mosaic moray^ GoVamosus. conger eels This is a small family of marine eels. They are distinguished from the morays by possessing pectoral fins and a black margin on the dorso-anal finc The dorsal fin begins above the pectoral fin * These are large powerful eels which can grow up to 3m long and weigh up to 80kgo They are found at moderate depths in most tropical and temperate seas of the world. Several conger eels are found in New Zealand waters„ found around the rocky coasts? Only two are the southern species, Conger verrauxi and the northern species, C.wiZsoni• The others occur in deep, offshore waters; Gnathophis habenatus3 G«ymbvettabia3 Bassanago bulbiceps and B.hivsutus. snake eels Snake eels are known throughout the world in tropical and subtropical seaso A few species range into temperate waters» brightly coloured and are often strikingly They are typically marked with bands or spots» Only a few of the many species reach lengths exceeding lm; less than 300mm long,» most of them are They dwell in shallow waters on coral and rocky reefs and also sandy and muddy bottoms» Some species are burrowing» They body is elongate, cylindrical and scaleless. The dorsal and anal fins are not confluent, leaving the tip of the tail free0 Pectoral fins are small or lacking and there is no caudal fin» The tail is stiff and sharp rather than broad and flat as in the morays» The snout may be short or long but usually projects beyond the lower jaw» The nostrils are located on two short stout barbels on top of the nose, which the eels use to probe into crevices and cavities in their search for food» 43 Family: Gfmsnothorais prasinus DESCRIPTION: - yellow Muraenidae moray This large, powerful eel grows to about 1m in length0 average size ranges between 500 and 600mm. The This species is easily recognised by its yellow or yellow-green uniformly coloured body* Other distinguishing features are-the absence of pectoral fins, the reduced gill openings and the long slender jaws. Several rows of sharp, prominent teeth are present in each jaw. The yellow morays are nocturnal, sheltering in cracks and crevices during the day. Individuals are solitary and home ranging and may return to use the smae shelter site each day. Although they will share a shelter hole with another individual belonging to a different species of moray, these fish may defend territories from other members of their species. Highly intensive aggressive encounters have been observed between yellow morays» DISTRIBUTION : Generals This species is widely distributed throughout the Indo-=Pacific region. In New Zealand they are found around the entire North Island coastline» They prefer areas of rocky coasts, especially around headlands. Local: In the Reserve, the yellow moray can be found on the rocky reef wherever there is suitable shelter. They are most abundant in broken, rocky areas. FEEDING: Morays forage actively at night, moving from cover to seek prey. Some feeding may occur during the day; however, foraging is probably confined to shelter holes. The diet consists mainly of crabs and small nocturnal fishes such as the scorpion fish, Scorpaena LIFE HISTORY: species. cardinaUs. No information is available on the life history of this 45 Family: Conger WBflSOra DESCRIPTION: conger Congridae eel The conger eel can be distinguished from the moray by its body form and colouration. It possesses small pectoral fins, the dorsal fin begins further along the back, the eyes are oval and much larger than the moray's and the dorso-anal fin is edged with black* Body colouration varies in these fish from a dark grey-blue black with a pale ventral surface to a pale brown back with a brown and white mottled undersurface. The average size is 750-900mm in length, but these fish can grow to reach 2m in length, weighing up to 18kg„ The males tend to be smaller than the females and have relatively larger head and eyes » Conger eels are solitary fisho They are nocturnal and inhabit narrow holes and crevices during the day» DISTRIBUTION: General: This species has been recorded from Australia, New Zealand and Lord Howe Island„ It is moderately common around the rocky coasts of the North Island but its southern extent is poorly known» Locals of the Reserve» Conger eels have been seen at all depths in the waters They are usually found in areas where the rock is broken and there are plenty of the deep holes and crevices which are required for sheltero FEEDING: CoWilsoni forages in the open at night» It is an opportunistic predator, taking any mobile animal of suitable size» eat mainly crabs and hermit crabs» Small conger eels The larger eels also take small reef fish, e.g. marblefish, A»meandratus; kelpfish, C.marmoratus and blennioid fishes o LIFE HISTORY: conger eel» Little is known of age, growth or breeding habits of the Females kept in aquaria as 3 million eggs» have been known to produce as many Cooger wilsoni to 2m New Zealand distribution Diet \ Hermit crabs 5 %