TANE 27, 1981

A CHECKLIST OF FISHES FROM CUVIER ISLAND, NORTH-EASTERN NEW ZEALAND

G.D. Housley, D.J. Riddell, and R.V. Grace* Department of Zoology, University of Auckland, Private Bag, Auckland *274a Birkdale Road, Birkenhead, Auckland 10

SUMMARY

Over a period of five days of scuba diving, 51 species of fish belonging to 28 families were identified around Cuvier Island.

INTRODUCTION

Cuvier Island is situated approximately 40 km east of the Coromandel Peninsula, north-eastern New Zealand. Influenced by the East Auckland Current, we would expect the fish fauna to be similar to that described from other islands off north-eastern New Zealand. The underwater topography in the study area varied from moderately sheltered shallow coves with low relief, to steep drop-offs with complex topography and depths exceeding 45 metres, thus providing a wide range of habitats.

METHODS

Nine areas were surveyed around the island, in areas sheltered from the westerly winds that prevailed over the five days from 21 to 25 May 1980 (Fig. 1). Four divers performed a total of 20 scuba dives of varying duration and depth, to a maximum of 45 metres. The fish species seen on all dives were combined from all areas for this checklist. Habitat notes were also made for each dive site.

RESULTS

51 species of fish from 28 families were identified and are listed below. Nomenclature generally follows that of Thompson (1981). In addition to the fish listed, a hybrid labrid (Ayling 1980) was noted which has not been further identified.

SPECIES LIST

Family Species Common name Myliobatidae Myliobatus tenuicaudatus Hector Eagleray

37 Muraenidae Gymnothorax prasinus {Richardson) Yellow moray G. ramosus (Griffin) Mosaic moray Gobieosocidae *Trachelochismus melobesia (Phillips) Barred clingfish Gadidae Lotella rhacinus (Richardson) Rock cod Exocoetidae Reporhamphus ihi (Phillips) Piper Trachichthyidae Hoplostethus elongatus (Gunther) Slender roughy Berycidae Trachichthodes affinis (Gunther) Golden snapper Zeidae Zeus faber Linnaeus John dory Scorpaenidae Scorpaena cardinatis Richardson Red scorpionfish Serranidae Ellerkeldia huntii (Hector) Red banded perch Caesioperca lepidoptera (Bloch & Schneider) Butterfly perch Carangidae Seriola grandis Castelnau Kingfish Caranx georgianus Cuvier Trevally Decapterus koheru (Hector) Koheru Arripidae Arripis trutta (Bloch & Schneider) Kahawai Sparidae Chrysophrys auratus (Bloch & Schneider) Snapper Mullidae Upeneichthys porosus (Cuvier & Valenciennes) Goat, fish Pempheridae Pempheris adspersa Griffin Big eye Kyphosidae Girella tricuspidata (Quoy & Gaimard) Parore Kyphosus sydneyanus (Gunther) Silver drummer Scorpis violaceus (Hutton) Blue maomao Pomacentridae Parma alboscapularis Allen & Hoesse Black angelfish Chromis dispilus Griffin Demoiselle C. hypsilepis (Gunther) Singlespot demoiselle Chironemidae Chironemus marmoratus (Gunther) Kelpfish Aplodactylidae Aplodactylus meandratus Richardson Marblefish Cheilodactylidae Cheilodactylus douglasi Hector Porae C. spectabilis Hutton Red moki Labridae Pseudolabrus celidotus (Bloch & Schneider) Paketi P. fucicola (Richardson) Banded wrasse P. miles (Bloch & Schneider) Scarlet wrasse P. inscriptus (Richardson) Green wrasse P. luculentus (Richardson) Orange wrasse Bodianus oxycephalus (Bleeker) Red pigfish Coris sandageri (Hector) Sandager's wrasse Suezichthys sp. Crimson cleanerfish (>

38 Fig. 1. The dive locations during May 1980 on Cuvier Island are shown.

F. sp. 6 (Doak 1972) Oblique-swimming blenny Gilloblennius tripennis (Bloch & Schneider) Spectacled blenny Notoclinops segmentatum (McCulloch & Phillips) Banded blenny Clinidae *Cristiceps aurantiacus Castelnau Crested weedfish Monacanthidae Parika scaber (Bloch & Schneider) Leatherjacket Diodontidae Allomycterus whitleyi Phillips Porcupinefish

« — species not considered for comparative purposes.

SITE NOTES

Three areas are discussed to relate general habitat to the fish fauna. Observations of special interest are also noted. LANDING BAY. Dives 1,2,8 & 9 Landing Bay is a mobile boulder beach which rises steeply above low water level but has a relatively gently sloping subtidal topography. The broken reef and boulder floor with kelpbeds of moderate density extends outwards for 200 metres. The brown algae Carpophyllum maschalocarpum and C. angustifolium in the shallows are gradually replaced by Ecklonia radiata in deeper water. At 15 metres depth, sand patches occur amongst the rocky areas. In the centre of the bay the topography is flatter with the hard rock substrate supporting little or no Ecklonia radiata, but a high density

39 of the urchin Evechinus chloroticus. Red pigfish (Bodianus oxycephalies) reach their highest density here. Very large schools of demoiselles (Chromis dispilus) and blue maomao (Scorpis violaceus) tend to be more common in the boulder areas with associated kelp closer to shore, where other labrids and red moki (Cheilodactylus spectabilis) are also common. 500 metres out from Landing Bay and to the west (see dive 8, Fig. 1), a surface reef runs out which drops steeply to 33 metres. Slopes around the reef are covered with Ecklonia radiata. Large hydroids and sponges, including the bright yellow Iophon sp., occur in the deeper water, with feather-stars (Comanthus novaezelandiae) being extremely common in places. The rare fanworm Protula bispiralis is found occasionally attached to rock near the sand at 30 metres. In this area two yellow morays (Gymnothorax prasinus) were seen to capture a red crayfish (Jasus edwardsii) under the abdomen and drag it into the crevice they occupied. FAIRCHILD BAY. Dives 5 & 7 Fairchild Bay is a mobile boulder beach similar to Landing Bay but partly sheltered by a large rock known as Scott's Monument. Juvenile black angelfish {Parma alboscapularis) were common in the shelter of boulder heaps in 2 metres of water. In this area juvenile trevally (Caranx georgianus) approximately 50 mm in length were seen to act as cleaners. When approached by an adult black angelfish, the trevally removed parasites from its flank. TOWER HILL POINT. Dives 4 & 6 At this site the rocky bottom dropped steeply into deep water (45 metres). Macroalgae typical of heavy wave-exposure (Carpophylium angustifolium and Lessonia variegata) were present in shallow water, with Ecklonia radiata appearing in deeper water. Near the surface, school fish such as koheru (Decapterus koheru) and kahawai (Arripis trutta) were common, replaced by abundant butterfly perch (Caesioperca lepidoptera) in deep water.

DISCUSSION

By reducing the number of species to a comparative list by the method outlined by Willan et al (1979), the list represents 49 species from 26 families for Cuvier Island. The number is very high considering the small number of dives undertaken and the somewhat compressed study boundaries due to bad weather. If comparison is made with the cumulative species sighting versus dive number curve of Nicholson (1979) for the Cavalli Islands, the 49 species recorded for Cuvier Island in twenty dives compares well with the 42 species in the first twenty dives at the Cavalli Islands. This could reflect an overall fish diversity greater at Cuvier Island than that of the Cavalli Islands

40 Group. Such a comparison, however, is valid only if diving effort was spread evenly through successive dives across all habitats represented. Direct comparison of the Cuvier list with standardised data from various sources throughout northern New Zealand, presented by Nicholson (1979), suggests that Cuvier Island (49 species from 26 families) ranks along with White Island (also 49 species from 26 families). Without "rate of discovery" information, however, comparison between areas is difficult because of the relationship between search time, habitats investigated, and the number of species seen - a difficulty pointed out by Nicholson (1979). It is clear, however, that the presence of certain species at Cuvier Island suggests a fairly strong influence from the oceanic subtropical East Auckland Current, as at many of the offshore islands of north• eastern New Zealand. Of particular note in this respect are Gymnothorax ramosus (mosaic moray), Chromis hypsilepis (single- spot demoiselle), Pseudolabrus inscriptis (green wrasse), P. luculentus (orange wrasse), Suezichthys sp. (crimson cleanerfish), and Forsterygion sp. 5 (blue-dot blenny).

ACKNOWLEDGEMENTS

The authors wish to thank Dr J.H. Choat for his helpful criticism of this paper, and Glenn White for his participation in the diving.

REFERENCES

Ayling, A.M. 1980: Hybridisation in the genus Pseudolabrus (Labridae). Copeia 1980: 176-180. Doak, W.T. 1972: "Fishes of the New Zealand Region". Hodder & Stoughton, Auckland. 132 p. Nicholson, J. 1979: A checklist of fishes from the Cavalli Islands, Northland, New Zealand. Tane25:133-139. Thompson, S. 1981: The fish of the Cape Rodney to Okakari Point Marine Reserve. Leigh Laboratory, University of Auckland. 364 p. Willan, R.C.; Dollimore, T.M. & Nicholson, J. 1979: A survey of fish populations at Karikari Peninsula, Northland, by SCUBA diving. New Zealand Journal of Marine and Freshwater Research 13(3): 447-458.

Note added in press: The Serranid Caproden longimanus (Gunther), pink maomao, not seen during this survey, has been confirmed as present at Cuvier Island by Mr John Peppiatt, who photographed several specimens in August 1981.

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