Hong Kong Amphibians and Reptiles (Second edition)

by Stephen J. Karsen, Michael Wai-neng Lau, Anthony Bogadek

Protected and Endangered Species

Several of the animals described in this book (python, sea turtles and minor lizard) are internationally recognised as 'Endangered Species'. They are listed in Appendices I and II of the Convention on International Trade in Endangered Species (known by its acronym CITES), to which over 140 countries are signatories. Hong Kong has implemented CITES since 1976. For the information of readers, the symbol (E) is used in the index after the species name to indicate this status.

The import, possession or export of such endangered species, including products derived from them, are strictly controlled by the law in Hong Kong and may only be done under licence from the Director of Agriculture and Fisheries. The Animal and Plants (Protection of Endangered Species) Ordinance, Chapter 187, gives local legislative backing to the international convention which controls trade in endangered species of wild flora and fauna. This convention seeks to rally attention of all progressive governments to the need for conservation of such plants and animals.

In addition, all local turtles and terrapins, Hong Kong Cascade Frog (Amolops hongkongensis), Hong Kong Newt (Paramesotriton hongkongensis) and Romer's Tree Frog (Philautus romeri) are listed under the Wild Animals Protection Ordinance, Chapter 170, and are protected accordingly.

Readers of this book are invited to lend their personal support to this principle by doing all they can for the welfare of these endangered or protected species. In particular, they should not collect living specimens of these species in the wild. Neither should they purchase commodities such as python skins or stuffed sea turtles which are commonly offered for sale by unscrupulous traders in the Southeast Asian region. In this way they will not only help in the conservation of these fascination creatures but will also save themselves considerable embarrassment and difficulty at customs clearance. Enquires for specific information on this subject should be addressed to the Director of Agriculture, Fisheries and Conservation.

Preface to the Second Edition

Being situated in the tropical region of Southeast Asia, Hong Kong has a great assemblage of amphibians and reptiles. For many years the need was felt for an illustrated comprehensive book on the amphibians and reptiles of Hong Kong. So the authors began observing these animals in the field and in captivity and taking photographs of them far back in 1976. Their findings were published by the Hong Kong Urban Council in the book "Hong Kong Amphibians and Reptiles" in 1986. The book was the first major publication exclusively on Hong Kong herpetology. It was well received locally and overseas and was soon sold out. The aim of this second edition remains the same, viz., to inform the general public about the rich diversity of amphibian and reptilian species that can be found throughout the territory of Hong Kong. The authors have gained considerable experience since 1986, and through their field work and the assistance of interested individuals, they have gathered new information on these animals. This second edition embodies the fruit of their research efforts over the past twelve years. It is hoped that the original information, now considerably expanded, will benefit a wider range of readers: biology teachers, their students, other interested naturalists and even professionals.

A notable feature of the second edition is the inclusion of some new topics: brief history of Hong Kong herpetology, description of habitats where reptiles and amphibians can be observed, simple keys to the identification of adult members of both groups and a fuller account of each species, particularly its habits, habitat and distribution. A few useful reference maps have been included. Many of the photographs have been changed in the interest of clarity and as a better aid to identification.

The number of local species has also increased as additional species have been recorded and at least one is new to science. A few other species were introduced and are now established well enough to be regarded as part of our herpetofauna. However, some of the species originally included in the first edition of our book have been relegated to a "problematic" section. The reasons for this are varied: (1) despite extensive searching, no new specimens have come to light; (2) Hong Kong lies well outside their natural geographic range; (3) suitable habitat is lacking locally. It might, however, be possible that populations of these species do occur in some isolated part of the territory that has not yet been thoroughly explored. For this reason they are still illustrated and described in this edition, but they have been placed in a separate section after the main section dealing with the known species.

As new, previously unrecorded species turn up from time to time, it was thought useful to make mention of a number of species that might be expected to occur in Hong Kong. The reason for this is that these species occur in mainland China not far from Hong Kong and are local habitats capable of supporting them. The authors would be very grateful for information about new sightings of the rarer species mentioned in the book as well as of any new discoveries so that a better picture of the distribution of amphibians and reptiles in Hong Kong may be built up.

As with the first edition, this work is dedicated to our friend, teacher and mentor, the great herpetologist J.D. Romer, who first got us interested in herpetology.

In addition to thanking all those persons who helped us with the first edition, we also wish to express our thanks to those who have assisted us in the production of this second edition, especially Dr. Gary Ades (Kadoorie Farm and Botanic Garden), Dr. H.G. Cogger (Australian Museum), Dr. T. Hikida (Kyoto University), Dr. J. Lazell (The Conservation Agency, Rhode Island), Eric Leung, Francis L.K. Lim (Singapore Zoological Gardens), Dr. J. Nabhitabhata (Thailand Institue of Scientific and Technological Research), Mr. Stephen Von Peltz, Gernot Vogel, Dr. Martin Williams, Dr. Wolfgang Wuster (University College of North Wales, Bangor) and WWF (Hong Kong) for lending colour photographs; Dr. R.T. Corlett of the Department of Ecology and Biodiversity (The University of Hong Kong) for assistance with the habitats section; Prof. Er-Mi Zhao (Chengdu Institute of Biology, China), Prof. Kraig Adler (Cornell University) and Prof. Hidetoshi Ota (Tropical Biosphere Research Center, Okinawa) for the loan of colour slides and literature; Prof. I.J. Hodgkiss (University of Hong Kong) and the Hong Kong Natural History Society for allowing the use of J.D. Romer's illustrations from their Natural History Memoirs series; Dr. Natalia B. Ananjeva, Dr. Ilya Darevsky and Dr. Nikolai Orlov (Russian Academy of Sciences, St. Petersburg) for answering our enquiries; Dr. Gary Ades, Sarndra Brown, Dr. J. Lazell, David Willott, Ron Clibborn-Dyer, Dr. B. Hollinrake, Dr. Chan Siu Mei, Andrew Cornish, Louise W.H. Li, Kevin Weng, Graham Reels, Dr. Francis Roy, Stan Ho, Raymond Kan, Bosco Chan, Roger Muscroft, David Lau, Sarbarjit Gurung, Jane Frohlich and Agriculture and Fisheries Department for providing rare specimens and/or first-hand information; the Director of Lands (HK Government) for permission to use the map of Hong Kong; Mr T.C. Yan for the photographic work and Ms. Susanna C.Y Kwok for the art work.

We are especially grateful to our friends, ecologist Dr. John Fellowes and herpetologist Professor Kraig Adler, for their critical reading of the manuscript, their painstaking corrections and the many valuable suggestions. We are sure that their professional competence has greatly increased the quality of this modest work.

Excerpts from the Preface to the First Edition

A book on the amphibians and reptiles of Hong Kong with has long been needed, and to the authors' knowledge this is the first such attempt.

The aim of this booklet is to familiarise the people of Hong Kong with the amphibians and reptiles of their territory. We hope it may also be of special help to biology teachers and their students. Characteristic feature, habits and habitat are given for each species.

This study covers the entire territory of Hong Kong, including the smallest off-shore islands and the adjacent seas. Most of the information was gleaned through the combined fieldwork of the three co-authors, assisted also by contributions from those person in the acknowledgements.

The photographic work posed special problems. As is generally known, amphibians and reptiles are very fast-moving animals. They are very alert to sound and movement, and disappear at the slightest disturbance. Many of them are cryptic. Some live in almost inaccessible terrain. Quite a few are nocturnal. To photograph them in their natural environment would have been quite a difficult and time-consuming task. Thus for purposes of photography, the specimens were captured and photographed on a semi-artificial setting during daylight. For sake of clarity too, water snakes were photographed out of water.

Reptiles are correctly identified by the scale pattern on their head, body and tail as well as by reference to their dentition. However, this is a rather technical matter. It may also be confusing to the inexperienced person as slight variations in scale count are often found. The method of identification used in this booklet relies on colour and general appearance of the animal and the nature of its habitat. This type of information may be more useful for the general public.

Most of the knowledge concerning the physiology and habits of the animals mentioned was obtained by the three co-authors by direct observation in the field or from live specimens in captivity. The authors believe that their laboratory observations, especially those related to feeding, are valid since amphibians and reptiles have very specialised diets and can seldom be induced to eat food that is not their natural diet.

Both amphibians and reptiles are very useful to our environment for controlling serious pests such as insects and rodent which damage crops and are a nuisance in semi-urban areas. For this reason they should be protected and not routinely exterminated. Many species are of commercial value locally, being used for food or medicinal preparations. Most market specimens come from China but several species in Hong Kong are declining due to over-collecting. Of the more abundant species, many specimens are collected and sold for the pet trade. There is, therefore, a need for conservation at all levels since over-collecting can very quickly reduce the numbers of a species and force it towards extinction. Some species are protected world-wide. These include:

The Green Turtle (Chelonia mydas)

The Pacific Ridley Turtle (Lepidochelys olivacea)

The Leatherback Turtle (Dermochelys coriacea)

The Water Monitor (Varanus salvator)

The Burmese Python (Python molurus bivittatus)

In Hong Kong all species of chelonians are protected. They should not be collected unless under a special permit obtained from the Agriculture, Fisheries and Conservation Department. 1