The Indian Medical Service had a distinguished history not only in its purpose of providing the medical requirements of the Indian army but also in improving civilian health. The medical officers often had wide research interests in such non-medical fields as natural history, chemistry, physics, languages and religions. One was awarded a Nobel Prize; several became Fellows of the Royal Society.
In 1900, Britain found itself short of troops. The Boer War was in full spate when the Boxer Rebellion in China broke out. In order to take part in the eight-nation alliance’s campaign, the British government sent troops from the Indian Army, including, therefore, the Indian Medical Service, to form the China Expeditionary Force. As a result, Captain Frank Wall found himself spending time in Shanghai and five and a half months in Hong Kong. Wall had a long interest in herpetology. He visited two museums in Shanghai and the City Hall Museum in Hong Kong in order to make a list of the snake species they had. In addition he visited private individuals with preserved snake collections as well collecting snakes himself.
On 15 December 1902 the Zoological Society of London received a paper from Frank Wall with the wonderful title of ‘A prodromus of the snakes hitherto recorded from China, Japan. and the Loo Choo islands; with some notes’; it was published in 1903. His list of snakes from Hong Kong included those he had found ‘in a swamp near the Sanatorium on the Peak, whilst being drained during the campaign against malarial mosquitoes’. His medical duties must have been at the military sanatorium where some of the Indian Army soldiers would have been patients. Long demolished, the site of the sanatorium is known, and there are photographs on the Gwulo website.
Wall was rather critical of the Hong Kong museum collection:
In the City Hall Museum in Hongkong, out of about one hundred specimens from the territory above mentioned, I found many misnamed and others unidentified. I was informed that during a typhoon some years previously a large case, containing specimens, was blown over and the contents wrecked. Out of the debris labels were recovered as far as possible and replaced, but some were evidently incorrectly reattached and others were destroyed. This circumstance may render the accuracy of some of the records open to question. That this collection is far from representative is evidenced by the fact that during five and a half months' residence in this Port I obtained six species which were not to be found in the Hongkong Museum.
It was not the specimens in the old museum, nor those he collected himself, that have echoed down the years for all those interested in the fauna of Hong Kong. After describing the known distribution of Dendrophis pictus, he wrote:
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One specimen of this snake in spirit was given me by a lady, who assured me she had obtained it on Hongkong Island.
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Who, incidentally, was the unidentified lady who kept a snake preserved in alcohol? There cannot be too many candidates amongst the residents of 1901.
In describing that one specimen from Hong Kong he started a debate which continued for 80-odd years. Was it a genuine record? The question was asked because that species had not been seen in the wild nor had any other preserved specimens turned up from any part of Hong Kong—Hong Kong island, the Kowloon peninsula, the mainland New Territories nor the offshore islands? Had the lady acquired it from a relict population wiped out by building work? Could it have been a stowaway in a ship’s cargo—a route of entry of a number of reptiles found in Hong Kong?
Checklists of Hong Kong snakes did, of course, continue to include what is now known as Dendrelaphis pictus, the Painted Bronze Back or Bronzeback. The first edition of the book on Hong Kong’s amphibians and reptiles published in 1986 included the species (with a photograph from elsewhere) in a full page entry, the same as other species. In a review I queried whether, in what was essentially a book aimed at popular readership, it might give the reader the impression that it might be have been or could be spotted in the wild. In the second edition, published in 1998, it was again included because there was positive news: another specimen of Dendrelaphis had turned up in unusual circumstances and in an unusual place.
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| Dendrelaphis pictus - photograph not from Hong Kong from Karsen SJ, Lau M W-N, Bogadek A. 1998 |
Passengers on the present fast boats from Hong Kong to Macau—and those in the old days on the slow boats—pass a number of islands in Hong Kong waters south of the large island of Lantau. One of these, on the port side heading for Macau, is where the specimen was found. Shek Kwu Chau, known to the old sailors as Coffin Island, was uninhabited until 1962. Then a drug rehabilitation centre was established on the island and it became, and remains, closed to visits by the public. The government medical officer at the centre from 1971 until 1984 was Dr James Barrie Hollinrake. During that time he accumulated a collection of pickled snakes, as James D. ‘Skip’ Lazell, who made long herpetological research visits to the islands, including Shek Kwu Chau, of Hong Kong in the 1980s, explained:
Dr Barrie Hollinrake, who runs the place, pickled anything that bit anyone on the island between 1971 and 1984. A medical doctor, he reasoned, that should the victim develop severe symptoms, treatment would depend on correct identification of the biter. Exactly so!
Amazingly, no one ever did develop symptoms, and Dr. Hollinrake was about to dispose of his collection when I heard about it. The snakes and spiders went to the Smithsonian (USNM), but jars and jars and dozens and dozens of vipers, kraits, and all those others—including the amazing, probably novel rarities, are now safely at the Museum of Comparative Zoology [Harvard].
In a paper published with his wife, Wenhua Lu, Lazell went on the write that among Hollinrake’s specimens was a ‘beautiful female Dendrelaphis pictus’. However, he was unable to compare this specimen with the one given to Frank Wall because what happened to the latter is not known. Wall gave all of his later material from India, Burma and Ceylon to the Natural History Museum in London when he retired. Lazell found the Hong Kong specimen was not there, nor, unsurprisingly, in Harvard. Could it still exist in some dusty museum collection? Did Wall take the pickled snake back with him to India where he was part of the IMS establishment in the Madras Presidency? Could it have been or, indeed, still be at the Chennai Museum, in operation since the 1840s? A further clue is contained in an article from 2016 in Hornbill, the magazine of the Bombay Natural History Society. That article states that he distributed specimens to many museum in India, ‘especially in the Natural History Section of Prince of Wales Museum of Western India, Mumbai’.
What has happened in the past 20 years? The latest reliable information I can find on the status of the Dendrelaphis specimen from Shek Kwu Chau is that written in 2012 for the entry in the IUCN Red List by Michael Lau, one of the authors of the 1986 and 1998 editions of the book on Hong Kong amphibians and reptiles and who had been on Shek Kwu Chau with Lazell. Key points are:
- There have been surveys in the island and no specimens have been found.
- Research is needed to determine if this is a valid species.
- The known specimen of this snake was referred to Dendrelaphis pictus by Karsen et al. (1998), although Lazell and Lu (1990) had previously recognized its distinctiveness. It was formally described as a new species by Lazell (2002). It is similar to D. subocularis, and Lazell (2002) hypothesizes that this may be a relict species that diverged from the common ancestor of this species and D. pictus. Wall (1903) reported D. pictus from Hong Kong; as this specimen has now been lost (Lazell and Lu 1990) it is unclear whether this record is referable to D. hollinrakei.
There have been a number of attempts to sort out the confused status of Dendrelaphis pictus (as far as I can see all based on classical quantitative morphological differences) which in its original sense ranged widely from India to Indonesia. There have been numerous taxonomic ‘splits’. Perhaps the question marks hanging over the whole Dendrelaphis genus explain why the Agriculture Fisheries and Conservation Department checklist of snakes simply lists Dendrelaphis sp. But even if the taxonomy of the Shek Kwu Chau specimen is re-examined as part of a wider assessment of the Dendrelaphis genus the problem remains of explaining why individuals have survived, or survived until comparatively recently, in seemingly very low numbers on one island, Shek Kwu Chau, and until over 100 years ago, possibly on another—Hong Kong Island—on the edge of the Pearl River Delta.
I find it odd that just as with Wall’s presumed specimen from Hong Kong Island no other sightings or specimens have turned up either on Shek Kwu Chau or on Lantau. Dendrelaphis species are active snakes, mainly arboreal and often out and about during daytime.
But that isn’t the only serpentine gem from Shek Kwu Chau. In Dr Hollinrake’s spirit jars were two Jade Vine Snakes or Oriental Whip Snakes, Ahaetulla prasina, a species never recorded dead or alive in Hong Kong, but known in South China. And then there’s the lizard, Bogadek’s Burrowing Lizard, first discovered in 1987 on Hei Ling Chau and then on the nearby Sunshine Island but also on Shek Kwu Chau…a story and species for another day.
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| I found I had Shek Kwu Chau in the background of a family photograph taken in 2017 on Lantau. The island is about 1.4 x 1.1 km |
There is a variety of views on old or relatively old records that seem ‘problematical’, ranging from the collector or reporter being mistaken, their discovery a fraud, a hoax or the result of intentional or accidental introduction, to the acceptance of the record as genuine for which a biological explanation must be sought. Is it possible that the Bronzeback and Oriental Whip Snake were present in Hong Kong and adjacent regions but brought to local extinction by events unknown, leaving relict populations on the offshore islands where they also slowly died out or been extirpated, being arboreal and easy to see, by an expanding or new human population?
Adam Francis has left the Bronze back out of his recent field guide for the obvious reason that the casual herper is highly unlikely to see one. However, If you find yourself wandering nonchalantly amongst trees and shrubs anywhere in the Hong Kong countryside and you spot a slender snake gliding amongst the twigs and branches, you will be entitled to shout Eureka! But carry the thought that most people hiking in Hong Kong never see a snake and the vast majority would not spot or recognise a Bronzeback. There is I suppose the possibility that some could have been hiding in plain sight since the unknown lady gave a pickled specimen to Captain Wall a hundred and twenty years ago.
Francis A, 2021. A Field Guide to the Snakes of Hong Kong. Hong Kong: Adam Francis with Robert Ferguson. ISBN 978-988-74586-2-3. 196 pages.
Karsen SJ, Lau M W-N, Bogadek A. 1986. Hong Kong Amphibians and Reptiles. First Edition. Hong Kong: Urban Council.
Karsen SJ, Lau M W-N, Bogadek A. 1998. Hong Kong Amphibians and Reptiles. Second Edition. Hong Kong: Provisional Urban Council. ISBN 962-7849-05-7
Lazell JD. 1993. Snakes of Shek Kwu Chau. Porcupine, January-February 1993 (4), 7.
Lazell JD. 2002. The herpetofauna of Shek Kwu Chau, South China Sea, with descriptions of two new colubrid snakes. Memoirs of the Hong Kong Natural History Society 25, 1-82.
Lazell JD, Lua W. 1990. Four remarkable reptiles from South China Sea Islands, Hong Kong Territory. Asiatic Herpetological Research 3, 64-66.
Peaker M. 1987. [Review of] Hong Kong Amphibians and Reptiles. Herptile 12, 36-37.
Wall F. 1903. A prodromus of the snakes hitherto recorded from China, Japan. and the Loo Choo islands; with some notes. Proceedings of the Zoological Society of London 1903, 84-102.
UPDATED 3 September 2021
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