Subject: Recent decisions of the RC 紀錄委員會最近對一些鳥種的議決 [Print This Page] Author: cgeoff Time: 27/10/2006 13:55 Subject: Recent decisions of the RC 紀錄委員會最近對一些鳥種的議決
At the recent Records Committee (RC) meeting of 18th October, as a result of research carried out by members of the RC that included examination of bird skins in the UK and photographs posted on the HKBWS Bulletin Board, a number of decisions were made regarding species on the HK List. The result is the addition of three species to Category A of the HK List, and the removal of one.
Yellowish-bellied Bush WarblerCettia acanthizoides
DNA analysis of samples from the 3rd and 4th records of this species, both in December 1998, identified these birds as Brownish-flanked Bush Warbler C. fortipes. Given the strong similarities in plumage and biometrics between these and the first two records, the retention of Yellowish-bellied Bush Warbler on the HK List is untenable. This species is removed from Category A of the HK List.
Northern Hawk CuckooHierococcyx hyperythrus
Having previously agreed to treat the four taxa hyperythrus, pectoralis, nisicolor and fugax as separate species based on vocalisations and morphology, records of autumn birds were examined in an attempt to decide whether other taxa were occurring. Based on an analysis of skins at the British Museum, Tring and examination of descriptions and photographs of Hong Kong records, the RC concluded that, in addition to existing spring records of Hodgson’s Hawk Cuckoo H. nisicolor, there are acceptable autumn records of hyperythrus. Thus, Northern Hawk Cuckoo Hierococcyx hyperythrus is added to Category A of the HK List.
Horsfield’s CuckooCuculus horsfieldi
Horsfield’s Cuckoo is on the HK List based on records of two trapped birds. Further work on identification criteria is ongoing, with a view to determining whether there are any records that can be assigned to Oriental Cuckoo C. saturatus, which would be an addition to the HK List. The Records Committee is very keen to see further photographs of these species taken in Hong Kong or on breeding grounds in south China, and encourages photographers to target this species. Photographs can be posted on the Forum, or sent direct to Geoff Carey (send a private message to get my email address). Please make sure details of location and date are provided, as far as possible.
Pale MartinRiparia diluta fohkienensis and Sand MartinR. riparia ijimae
On the basis of a review of skins at the British Museum, Tring, and photographs of birds taken in HK, evidence was presented to support the separation on plumage and structural characters of these two taxa. It was concluded that both taxa occur. As a result, Pale Martin R.d. fohkienenis and Sand Martin R.r. ijimae were admitted to Category A of the HK List. Of these, Pale Martin is a species new to the List.
Spot-billed DuckAnas poecilorhyncha zonorhyncha and A.p. haringtoni
In view of the sympatric breeding that occurs in HK, the low rate of hybridisation and clear morphological differences, separation of Spot-billed Duck into two species was agreed. A paper prepared by Paul Leader is in press with the Bulletin of the British Ornithologists Club. The two species are: Anas poecilorhyncha haringtoni (colloquially known as ‘Burmese’ Spotbill) Anas zonorhyncha (monotypic)
The choice of English name remains under discussion. Possibilities are retaining the phrase ‘Spot-billed Duck’ in each name, or ‘Spotbill’ or ‘Yellownib’ or ‘Yellow-nibbed Duck’. The RC would be happy to receive opinions on this.
Full details on all these decisions will be provided by ‘Records Committee Statement No. 3’, which will be posted on the website in due course.
Acknowledgement
The RC wishes to thank Robert Prys-Jones and Mark Adams at the British Museum, Tring for facilitating access to the bird collection.
Geoff Carey
Chairman, Records Committee
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