Zoology Jottings: Tokay Geckos in Hong Kong: wild and/or feral populations?

Tokay geckos are recognized to happen on the island of Lantau, within the mainland New Territories and on Hong Kong island. The brand new paper on the commerce in Tokay geckos in Hong Kong I referred to in a earlier article discovered recommendations that not less than one of many populations within the New Territories comprises the red-spotted morph, indicating a non-Hong Kong origin and sure the results of introduction both by escape of captive geckos or deliberate launch. The authors concluded:

Our genetic evaluation exhibits that TCM [traditional Chinese medicine] commerce in Hong Kong shouldn’t be doubtless equipped by native wild populations, however by imports from Southeast Asia. Further info from SIA [stable isotope analysis] helps our genetic findings, as we detected little or no overlap in isotopic signatures between TCM and Hong Kong wild tokays. Commerce additionally results in mixing of populations by means of introductions associated to the dwell pet commerce. We discovered that not less than two Hong Kong wild tokay populations had been doubtless established from launched pets. 

The conclusion that Tokay Geckos should not now collected from the wild in Hong Kong suggests a change has occurred because the first discovery of Tokay Geckos within the wild on Lantau Island on 23 February 1950 since that discovery was solely made when the supply of dwell geckos on the market in a snake store got here to mild.

The grand outdated man of Hong Kong herpetology, John Dudley Romer (1920-1982) wrote within the journal Copeia:

On February 23, 1950, I bought a dwell grownup Gekko gecko from one of many snake-dealers, and on making enquiries concerning its origin, was knowledgeable that it had been obtained from Tung Chung. Just a few days later I visited that locality with some mates and enquiries on arrival without delay revealed that this gecko is well-known to the native Chinese language. One dwell grownup specimen was obtained from a girl who had apparently been preserving it to promote within the metropolis. Since time was brief we engaged one of many villagers to indicate us precisely the place the geckos had been discovered, and after an hour or two of stiff climbing, he lastly halted on a rocky hillside and identified a number of slender clefts in some notably giant rocks. It was then only some minutes earlier than we noticed certainly one of these large geckoes in a cleft in one of many rocks.

John went on to counsel that the gecko might have been extra extensively distributed in Hong Kong because it had not been discovered within the typical habitats of this species, in northern Burma for instance: “homes, huts and bushes and at nights are sometimes seen on fence posts. In forests they dwell in holes or on the bark of bushes.” He concluded:

It appears doubtless that their absence from dwellings and obvious confinement to the rocks on lonely hill-sides on this colony could also be associated to their extermination from different varieties of habitat.

In different phrases, he was suggesting that the inhabitants on Lantau was a relict of a as soon as a lot wider distribution throughout Hong Kong. The invention of a second inhabitants on Lion Rock within the New Territories might give credence to such a proof.

When the second version of Hong Kong Reptiles and Amphibians was compiled and printed in 1998, the populations on Lantau and on Lion Rock had been thought of native; plainly conclusion nonetheless holds.

These arriving or leaving Hong Kong by air will, if sitting on the facet nearest the mountains of Lantau might be passing the location John Romer described. Nonetheless, his fishing village of Tung Chung is now  the closest city to the Chek Lap Kok airport with a inhabitants of over 1000,000 and nonetheless rising. If vacationers ever return Hong Kong, the Ngong Ping Cable Automotive hyperlinks Tung Chung to the Po Lin Monastery and Huge Buddha. The as soon as tough to succeed in village is now simply one other cease on the MTR.

The web page on the Tokay Gecko from Karsen, Lau and Bogadek’s Hong Kong Amphibians and Reptiles

Dufour PC, Miot EF, So TC, Tang SL, Jones EE, Kong TC, Yuan FL, Sung Y-H, Dingle C, Bonebrake TC. 2022 House and hub: pet commerce and conventional drugs influence reptile populations in supply areas and locations. Proceedings of the Royal Society B 289:20221011 doi.org/10.1098/rspb.2022.1011 

Karsen SJ, Lau M W-N, Bogadek A. 1998. Hong Kong Amphibians and Reptiles. Second Version. Hong Kong: Provisional City Council. ISBN 962-7849-05-7

Romer JD. 1951. The prevalence of the lizard Gekko gecko within the colony of Hong Hong. Copeia 1951, 80.