T A N E 27,1981

R E P T I L E S O F T H E N O R T H C A P E R E G I O N , N E W Z E A L A N D by John M c C a l l u m

Department of Geology, University of Auckland, Private Bag, Auckland

S U M M A R Y Nine species of reptiles are currently known from N o r t h Cape: the

geckoes Naultinus grayi, Hoplodactylus duvauceli and H. pacificus; the skinks Cyclodina aenea, C. ornata, Leiolopisma smithi and L. suteri; and the loggerhead sea turtle (Caretta caretta). The tuatara is known from subfossil remains.

I N T R O D U C T I O N

The reptile fauna of the N o r t h Cape region of New Zealand has received scant attention by herpetologists and only five species (Naultinus grayi, Hoplodactylus duvauceli, Leiolopisma smithi, L. suteri and Sphenodon punctatus) have previously been documented.

The N o r t h Cape area extends from 172°38' E to 173°03' E and 34°23'S to 34°31 'S (see F i g . 1); a large portion is contained wi th in the Te P a k i F a r m Park (c. 21 000 hectares). N o r t h Cape consists of Lower Tert iary basic volcanics, Cretaceous (?) volcanic intrusives, Miocene sandstones and Quaternary swamp and sand deposits. Sand tombolos

Fig. 1. The North Cape region, showing locations mentioned in the text.

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provide connection w i t h the rest of Northland. Repeated burnings over the past 100 years have reduced the vegetation cover to small isolated pockets of broadleaf/podocarp forest, regenerating scrub communities of predominantly Leptospermum and grazed pasture. The coastline is comprised of rocky shores, shingle and extensive sand beaches.

Fauna surveys of the N o r t h Cape area were conducted during three trips w i th the A u c k l a n d Univers i ty F ie ld Club; the first two were based at Tapotupotu B a y (10 — 19 November 1979 and 4 — 11 J u l y 1981), while the th ird was at the Te Werahi Stream (26 — 28 December 1981). S ix species of lizards were recorded during these vis i ts and C. aenea, C. ornata and H. pacificus constitute new reports for the region.

A N N O T A T E D S P E C I E S L I S T

Order Rhynchocephalia Sphenodon punctatus (Gray 1842).

The tuatara is known from N o r t h Cape only from subfossil remains. Few are known to be associated w i t h M a o r i middens and most of the skeletal material would have originated from natural populations which occurred i n the area when the vegetation was more suitable (and before the introduction of exotic predators e.g. rats) (P.R. Mi l lener pers. comm.).

Order Squamata Hoplodactylus duvauceli (Dumeril & B ibron 1836).

Three specimens i n the Otago M u s e u m ( O M 98.93) are labelled as Cape M a r i a van Diemen (McCann 1955). I t is possible that they originated from Motuopao Island, which was a manned lighthouse station (operating from 1879 to 1941) and thus a l ikely point of collection ( A . H . Whitaker pers. comm.).

Motupao Island was not visited during these three surveys. It has been modified w i t h most of its vegetation removed; the status of its wildlife is uncertain. H. pacificus (Gray 1842).

Few mainland localities of H. pacificus are known i n Northland; localities are given at K a r i k a r i Peninsula and K a i t a i a by Robb and Rowlands (1977). Several individuals were found i n boulder piles near M t . T ir ikawa, but they can also be expected to inhabit cliffs and similar habitats which provide protection from rat predation. Naultinus grayi B e l l 1843.

Smal l scattered populations were located i n Leptospermum scrub. The distribution of this species has probably been the one most influenced by the early farming practise of repeatedly burning off the scrubland. Populations have probably radiated from undamaged stands of vegetation, usually i n the headwaters of catchments, into

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regenerating teatree (Leptospermum ericoides and L. scoparium). This gecko has been recorded from Te Werahi Stream, Spirits B a y , M t . T ir ikawa and M t Unuwhao ( A . H . Whitaker pers. comm.). Cyclodina aenea (Girand 1857).

Common in suitable habitats which range from open pasture to forest where they are usually found under rocks or logs. Localities include Pandora, Tapotupotu B a y and eastern T o m Bowl ing B a y . C. ornata (Gray 1843).

This species was located i n similar habitats to C. aenea. The two species occurred sympatrically in several localities e.g. beneath macrocarpa trees and regenerating scrub at Pandora. Leiolopisma smithi (Gray 1845).

Several were located amongst sand dunes at Pandora while a dense population was found in stone beaches at Tapotupotu Bay . A specimen from Twi l ight Beach is held in the A u c k l a n d Institute and M u s e u m ( A I M Rep 33.13). L. suteri (Boulenger 1906).

Four were found in boulder beaches at Tapotupotu B a y . Other mainland localities for L. suteri include Taupo B a y and parts of the Coromandel Peninsula, where they invariably occur i n rocky/stoney habitats. H a r d y (1977) suggests raft ing is the primary mechanism for its dispersal and that sandy shorelines may act as barriers to subsequent overland movement. This could explain the isolated Tapotupotu B a y population.

Order Chelonia Careta careta (Linne 1766).

D u r i n g M a r c h 1980, a juvenile loggerhead turtle was found washed ashore on Ninety M i l e Beach and died shortly afterwards (V. Hensley pers. comm.). The specimen is shown in F i g . 2. The loggerhead is the most frequent of the four marine turtles which are known to v is i t New Zealand waters.

D I S C U S S I O N

The arr ival of the Gekkonidae in New Zealand, probably by raft ing, is postulated as the early Miocene, w i t h a number of speciations occurring during the Plio-Pleistocene ice ages (Bul l and Whitaker 1975). D u r i n g the Pliocene, the Northland Peninsula consisted of an island archipelago which influenced speciation of land molluscs (Powell 1949) and possibly initiated some speciation within the genus Leiolopisma (Hardy 1977). It seems reasonable to speculate that Naultinus grayi, which is allopatric w i th N. elegans, also originated i n one of these northern islands.

It is interesting that H. granulatus and H. maculatus have not been recorded from the N o r t h Cape area to date. A l though the region may be

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Fig. 2. Juvenile loggerhead turtle found at Ninety Mile Beach in March 1980 by V. Hensley. Length c.300 mm. (Photo by R.N. Thomas).

north of their geographical range, lack of intensive searching could be the reason for their apparent absence, as they occur throughout most of New Zealand. It is possible that the sand tambolos connecting N o r t h Cape to Northland have acted as a barrier to the northern spread of these two species.

Subfossil remains of large skinks (Cyclodina l) and geckoes have been found in sand dunes at the F a r N o r t h (P.R. Mil lener pers. comm.). Whitaker (1978) discusses reptiles and rat predation i n detail and has shown that i t is usually the larger species that are most vulnerable to predation. H e suggests that many reptiles w i t h relic distributions may have once ranged over much of the N o r t h Island before the introduction of rats, the first being the kiore (Rattus exulans) which is presumed to have arrived wi th the Polynesians sometime after 1 000 A D .

A C K N O W L E D G E M E N T S

I would like to thank B.W. Thomas and A . H . Whitaker for their efforts in the preparation of this paper; V . Hensley and I.J. Bell for their contribution of data; R.N. Thomas for his photograph of the loggerhead turtle; and all those who were present on the three visits.

R E F E R E N C E S

Bull, P.C. & Whitaker, A . H . 1975: The amphibians, reptiles, birds, and mammals. Pp. 231 -276. In Kuschel. G. (Ed.). "Biogeography and Ecology in New Zealand". Junk, The Hague.

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Crook. I.G. 1975: The tuatara. Pp. 331-352. In Kuschel, G. (Ed.). "Biography and Ecology in New Zealand". Junk. The Hague.

Hardy, G.S. 1977: The New Zealand Scincidae (Reptilia: Lacertilia); a taxonomic and zoogeographic study. New Zealand Journal of Zoology 4:221-325.

McCann, C M . 1955: The lizards of New Zealand. Dominion Museum Bulletin 17. 127 p. Powell, A .W.B . 1949: The species problem in New Zealand land snails. Transactions of the

Royal Society of New Zealand 77:202-208. Robb, J . & Rowlands, R.P.V. 1977: Reinstatement of Hoplodactylus maculatus

(Boulenger) with redescription of H. pacificus (Gray). (Reptilia: Squamata: Gekkonidae). Records of the Auckland Institute and Museum 14:133-142.

Whitaker, A . H . 1978: The effects of rodents on reptiles and amphibians. In Dingwall, P.R.; Atkinson, I .A .E. & Hay, C. (Eds.). "The ecology and control of rodents in New Zealand nature reserves". Department of Lands and Survey Information Series No. 4: 75-88.

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