MUSEUM OF NATURE

Press, Volume CVI, Issue 31221, 19 November 1966, Page 12

MUSEUM OF NATURE

(Contributed by (

Canterbury Museum)

TF only you could catch them, you could give a gecko or a skink to every person in Christchurch. A quarter of a million lizards live amongst the pebbles behind the beach at Birdlings Flat and on the rock outcrops of the nearby hills. *

If you are an early visitor to the beach, you may see the last gecko padding noiselessly back into the dark crevices to begin his daytime slumber. But in the heat of the day, the lizard you send scuttling away into the grass is more likely to be a skink disturbed near his favourite sunbathing stone. You can easily tell the two apart. The glossy, snake-like, slender skink is clad in closefitting scaled armour. He moves very quickly, has a small inquisitive head and long fingers and toes. The stocky, short-toed gecko wears a loose-fitting, even wrinkled, skin with hardly-visible scales. By comparison with the skink, his head seems large and his manner phlegmatic. Hinged Skull During the day the gecko rests, often with several companions, between rocks where there are sufficient gaps to provide concealed underground escape routes. His favourite places are near the bases of low shrubs, and established lizard homes are recognisable by a “wallpapering” of white droppings on the surrounding rocks. At dusk, the gecko begins to nudge his way toward the trunk of the shrub, flattening

his body to squeeze through very small cracks. He can even flatten his head thanks to his peculiar hinged skull. Feeding Time Once above the ground he jumps and climbs into the branches, little suction-pads on his toes and a monkeylike grasping tail helping him to scale even smooth branches with ease. He watches for the movement of scarabbeetles, -moths or leafhoppers. Amongst the topmost branches, dusk-swarming caddis-flies fall victim to his strong, snapping jaws. A good feed, and at dawn he disappears under the stones to rest again. In winter cold, geckos and skinks may hardly feed at all. Sometimes nests of a hundred or more hibernating lizards ar? found, mainly geckos, but sometimes skinks as well, intimately entwined. There is slight concern if neighbour inadvertently treads on your nose—after all, you are sitting on next-door’s tail. In the lizard world, activity and argument very definitely depend upon the heat of the moment. A fine sunny day and the nest breaks up, skinks to day feeding, the geckos at dusk to the bushes. In very humid weather, the gecko will frequently change his clothes. He moults his skin in a single piece, start-

ing at his nose and rolling back the loose skin as he rubs through the pebbles. When half undressed, his face is framed by a lacy white bonnet, and when he fas finished his skin is left amongst the rocks, a perfect replica even to the transparent windows of skin which had covered his eyes.

In the warm late-autumn evening, the heavily-built square-jawed male gecko, newly moulted and so in a brighter coloured coat, feels ready to find a mate. Other males likewise .. . and threatening displays ensue when male meets male, bodies arched like miniature dinosaurs.

The female, the object of the fight, is not concerned. She may stay, but more likely she will move away to find another mate. When a male succeeds in obtaining her interest there is only a short struggle and then submission —and the partners leave each other without a backward glance. There is a long development of the young, through winter, spring and summer. The body of the female becomes distinctly pear-shaped and at the end of summer the young, usually twins, are born, each an inch and a half long, and exactly resembling their parents. Short “Childhood” No love is lost between mother and young. After an initial moult each tiny gecko moves away to catch its first insect and fend for itself. This is, no doubt, the most precarious stage in its life. If birth occurs well before the onset of winter, it may be able to catch sufficient insects to build up a reserve of food which it stores as fat in its tail. But if it is born near the onset of colder weather, it cannot easily capture the few .insects about, and it is still too small to harvest the abundant berries relished by the adult gecko at this time of year. So it has slim chance of survival over the winter. The adult, too, depends on the food he has stored in his tail to survive the winter. But he is likely to have put all his eggs in one basket, when, without a second thought, he discards his tail in escaping from sheep and cattle which disturb the pebbles where he hides, or when you wrongly catch him by this long, no doubt convenient appendage. His tail will grow again, but not without sufficient food. Almost half the geckos you find will have lost their original tails and be carrying perhaps their second or third. The new tail always has a slightly different colour or pattern. Have a look at the next One you catch, or at the skinks and geckos displayed in the Hutton Hall at the Canterbury Museum and see how few still have their original tails.— M.M.D.

The sketch shows the sun-loving skink above the ground and the dusky short-toed gecko in hiding. The gecko has a regenerated tail with different markings from the rest of the body and it is swollen with stored food.