NATURAL HISTORY
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More than 340 species of birds have been recorded in an apparently wild state during the past 50 years and a number of other species such as the Rose-ringed Para- keet, Sulphur Crested Cockatoo and the Common Mynah have been introduced. Species recently added to Hong Kong's list include White-capped Redstart, Pallas' Blue Robin and Citrine Wagtail.
About 12 field outings are held each year by the Hong Kong Bird Watching Society and these provide an opportunity for both simple enjoyment and serious study of bird life. There is plenty of scope for amateur studies since little is known of the ecology of even the common species.
Chinese Pond Herons, Cattle and Little Egrets regularly nest at the Yim Tso Ha egretry and one or two pairs of the rare Swinhoe's Egret have nested there for more than 10 years. A small number of Night Herons have also nested since 1972. This egretry is a strict nature reserve under the Wild Birds and Wild Mammals Protection Ordinance.
Even in the urban areas the Chinese Bulbul and Crested Mynah can be seen and the Black-eared Kite is a familiar sight around the harbour area. The Agriculture and Fisheries Department is conducting an ecological study of the Black-eared Kite in relation to the bird-strike hazard at Hong Kong International Airport.
Snakes, lizards and frogs are plentiful in Hong Kong. There are also various species of terrapins and turtles, although none are common. 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 Bam- boo 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 Corals prey almost exclusively on other snakes. Several species of sea snakes, all ven- omous, 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.
A further four species of butterflies were recorded for the first time during the year, bringing the total to 214 recorded species and forms in Hong Kong. Although many of the colourful butterflies are beautiful, the two commonly found types of Cabbage White butterflies are pests of economic importance, as their larvae cause considerable damage among the farmers' crops of brassica vegetables. Among the many local moths, the giant silkworm moths are noted for their large size and they occurred in unusually large numbers during the year. These moths include the Cynthia, the Fawn and Golden Emperor, and the Moon and Atlas moths. The Moon species has an average wing span of seven inches and the Atlas Moth nine inches. The beautiful Lantern Fly, closely related to cicadas, has delicately coloured wings and a remarkably