ENG-1973 — Page 272

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NATURAL HISTORY

The largest species, the spotted-billed pelican, comes in small numbers as a winter visitor to the Mai Po Marshes. Among the smallest are the insectivorous white-eyes of the wooded areas and the yellow-bellied wren warbler of the reed beds. The Chinese blue magpie, with royal blue plumage and orange beak, and the crow pheasant, which has dark brown plumage with light brown wings, can frequently be seen on the shrubby and wooded hillsides. The crow pheasant is in fact neither crow nor pheasant, but a cuckoo. Its haunting call of descending notes can be heard in spring and early summer. The bulbul and the minute tailor bird with its insistent 'tch tch' call are common birds in urban areas; while the beautiful song of the hwamei delights hikers and residents in the countryside.

Snakes, lizards and frogs are plentiful in Hong Kong. There are also various species of terrapins and turtles. Most of the snakes are non-poisonous and death from snake bite is extremely rare. Apart from back-fanged species, not dangerous to man, the venomous land snakes are: The banded krait, with black and yellow bands; the many-banded krait with black and white bands; Macclelland's coral snake, which is coral red with narrow, black transverse bars; the Chinese cobra and the hamadryad or king cobra, both of which are hooded; the rare mountain pit viper and the white- lipped pit viper or bamboo snake. The bamboo snake is bright green and, although less venomous than others, is more often seen and more likely to attack if accidentally disturbed. The hamadryad, kraits and coral snake prey almost exclusively on other snakes. Several species of sea snakes, all venomous, are found in Hong Kong waters but have never been known to attack bathers. An amphibian of special interest is the Hong Kong newt, which has not been recorded anywhere else in the region.

One of the rarest of the 210 recorded species and forms of butterflies in Hong Kong is the colourful tailed judy. This species was first recorded at Pak Ngau Shek in 1973. Of the many local moths the giant silkworm moths are remarkable for their size. These include the Cynthia, the fawn and golden emperor moths, and the moon and atlas moths. The moon species has an average wing span of seven inches and the atlas moth nine inches. Other commonly found insects include many types of dragon and damsel flies, metallic coloured beetles, and solitary wasps. The beautiful lantern fly, closely related to the cicada, has delicately coloured wings and a remarkably long forehead. Shrill calls of several species of cicadas are commonly heard in the country- side during spring and autumn.

Land molluses include the giant African snail, measuring up to six inches long, which was introduced and has become a crop pest, and a large black slug, Veronicella, a species sufficiently different from all other slugs to be placed in a separate family.

Aquatic Life

Being diverse in variety, form and colour, marine life in Hong Kong waters used to sustain a profitable inshore fishery. The yellowtail (Seriola quinquilineata), mackerels (Scomberomorus species), yellow croaker (Pseudosciaena arocea) and a number of other schooling species appeared seasonally in commercially exploitable quantities. However, in the course of development these resources (with the exception of certain