New Zealand Lizards

New Zealand Herald, Volume LXXIII, Issue 22402, 24 April 1936, Page 11 (Supplement)

New Zealand Lizards

T AST week n photograph of a tuatara appeared at tho head of this column and was described in tho title as NewZealand's only reptile. This statement should have referred to the tuatara as New Zealand's only largo reptile, for as it stood it ignored our several species of small native lizards. Tho slight may bo atoned for by devoting this week's article to lizards, and the subject may bo of interest to those correspondents who have written recently to ask if native lizards can bo kept successfully in captivity.- Thoro are no introduced reptiles in New Zealand except a few stray tortoises, and all the lizards, even the common ones, are native species. So far some 14 species have been described, and there may bo a few more awaiting discovery on outlying islands. They belong to two families: tho geckos, which are broad-headed and have soft skins, with scales only 011 head and belly, and the skinks, which arc smooth and scaly all over and have small compressed heads. Our commonest lizards, found under stones and logs, are skinks. They are diurnal in habits, but so swift and elusive that few observers liavo succeeded in recording much of their habits. Tndced, observation of and experiment with skinks in New Zealand lias not progressed far beyond the activities of inquisitive small boys who cause the lizard to disengage himself from his tail and then argue as to whether the reptile will come back and hook on the old tail or grow a new one. Of this problem it may bo ro-

marked in passing that the former action has not been observed, but that there is abundant evidence of the latter to be seen in the patently new tails on many lizards which do not match either the contour or the colour of the rest of the body. That the breaking off of the tail is possible without severe injury to the lizard is due to the presence of cartilaginous bands between certain of the tail vertebrae, these making points of weakness. It is not uncommon for the new tail to bifurcate and grow double, and a further interesting point that has been noticed is that when the scaling of a new tail differs from the original it reverts to a pattern characteristic of a simpler and possibly ancestral group. The several native skinks all belong on one genus, and are similar in general appearance, although they seem to differ in habits. Most of them are found inland, with a preference for dry situations, and their food consists of small insects. There is, however, a black, shiny-skinned species found on many islets which frequents the shore and departs in many of its habits from normal skink behaviour as defined by the text-book. On a falling tide I have seen these short-tailed lizards emerge from the cover of rocks and driftwood and hunt small crustaceans around the edges of the rock pools. This unusual lizard diet is further varied at high water with an occasional meal of berries. Skinks, unlike many lizards, do not climb trees, but on these islets where the coprosma, known, as taupata, grows in prostrate fashion, the skinks can easily reach the orangecoloured berries from the ground, and they do so by stretching up in a very pretty way. This same skink seems also

By R. A. P'ALLA

to be oviparous, laying a large white egg, whereas most other species arc viviparous. Lizards of tho other family found here, tho geckos, are much easier to observe. Although much less numerous than tho skinks, they are less timid and can be kept under observation in suitable cages when necessary. One of tho first species to attract attention in New Zealand was tho green lizard, attractive because of its brilliant colour, and regarded with sopio superstitious dread by the Maoris, who call it kakariki. The velvety skin of this lizard is usually green in colour, but a number of varieties have been described in which yellow spots, blotches, or stripes form various patterns. Puro sulphur yellow specimens are also known, and they appear to be only a colour variety of the green. There is no evidence that the various colours correspond in any way with tho particular environment of the specimens, and a good range can be found in any on'O locality. Tho species socms to bo both terrestrial and arboreal in habit. Green lizards are frequently kept in captivity so that their habits may be observed, but no description has yet been published to improve on the observations made by William Colenso in 1878. He kept three for a year and was able to record their partial hibernation during the winter months, and their method of taking their prey when active again in the summer. He writes: "When tho lizard clearly sees a fly and

makes sure it is living, it steals toward it in the most stealthy manner. As it nears the fly, and when within two inches, then is the time to watch closely its actions. First it arches its neck to a tolerably sharp angle, and its eyes swell and bulge out, or rather upwards, over their orbits, and the expression of its countenance alters greatly, taking on a fierce look. It lifts up its little hand-like paws and moves them, only a toe or finger at a time, and often in the air, very slowly and cautiously, much as a little child moves its hands when stealing along on tiptoe. Then it nears its head toward its prey, but so very slowly that I have better detected its movement by watching its shadow cast on marked paper by strong sunlight, reminding me of the almost imperceptible, movement of the hour-liand of a clock. At last it has got to one inch or a little less from the fly. As quick as light the dart is made and the fly is caught; and the little lizard rapidly knocks about its prey from side to side, as a terrier with a rat, not, however, striking the fly against anything, but merely shaking it. After a short time spent in that manner, the lizard proceeds to swallow the fly, which it does by half opening its mouth and drawing it up, and generally, after three or four movements of this kind, the fly is gulped down whole, legs and wings and bristles." A supply of small flies for captive lizards can be maintained by allowing fruit to decay in the cage. They are also fond of honey and should be kept supplied with clean water in a small dish. The limits of space for this account of lizards will not permit a description of the other native geckos, whose interesting habits must be reserved for later description.