The first edition of ‘The Avifauna of Hong Kong’ was published in 2001 (Carey et al. 2001) and looked at all records submitted to the Hong Kong Bird Watching Society (HKBWS) up to the end of 1998. By then the number of species considered to have occurred in HK naturally stood at 448; by the end of 2020 at least 100 species had been added to this list (excluding taxonomic changes) at an average rate of approximately five new species per year.

This online edition provides a comprehensive update that includes records submitted up to the end of 2020. Where appropriate, for a small number of species photographs or other data from subsequent years have been used. The focus of this edition has been on the period since 1999 in order to provide an up-to-date description of the status of all species considered to have arrived naturally or to have an established population.

Both birdwatcher activity and observer reporting have increased this century, in particular since 2010. While this is a welcome trend, it makes it problematic to assess changes in the status of those species not included in systematic surveys. Against this background of increased observer submission and other things being equal, species whose recorded numbers have declined or seem to have remained constant are likely to be decreasing. Unfortunately, declines are much more numerous than apparent increases.

Anthropogenic habitat changes continue apace. At the same time, however, efforts to conserve and improve habitat, especially wetland in the northwest New Territories, give cause for optimism in the short to medium-term at least. Forest cover in HK is increasing as reflected in colonisation by forest-dependent species and increased numbers of once rare species. The flip side, however, is that open-country grassland and grassland-shrubland specialists are in decline as vegetation succession occurs (and as development spreads). Regionally, loss of intertidal mudflats in the Yellow Sea and forests in Siberia appear to have had an impact on the numbers of some migrant species passing through. It is hoped that this work can contribute to the monitoring of these changes and, hopefully, stimulate conservation action to protect birds and the habitats on which they depend.

Compared to the first edition, the species accounts have been enlarged to include sections on Identification, Vocalisations, Breeding, Behaviour, Foraging and Diet and Conservation Status. The sections have been arranged in an order that will be of most use in the field when presented with a bird that appears unfamiliar or unusual for the time of year. Birdwatchers may also consult the HKBWS field guide to the birds of HK and South China (HKBWS 2022).

The typical contents of each section are as follows.

Hong Kong Status

A brief summary of the status and habitat preference in HK, and any changes or threats arising from habitat change if relevant. The category of the HK List in which the species is listed is also provided. The category definitions are as follows:

Category I: species that have been recorded in an apparently wild state in HK.

Category IIA: southeast China breeding species, the currently established HK breeding population of which is considered to derive from captive stock, but which probably occurred in HK prior to habitat changes.

Category IIB: extralimital species that, although originally introduced to HK by man, maintain a regular feral breeding stock without necessary recourse to further introduction.

Category IIC: previously established feral species.

A third category exists containing species for which all published HK records are considered likely to relate to birds that have escaped or have been released from captivity. However, species accounts have not been prepared for these.

Identification

A description of key size and plumage features sufficient to allow identification of most birds seen in HK; however, this is not a comprehensive field guide and reference to other sources should be made for more detail. Both in this section and others, if reference is made to another species on the HK List, no scientific name is provided; for species that have not occurred in HK, the scientific name is provided.

As far as possible photographs taken in HK have been selected; the location of such photographs is not stated. Any photographs taken outside HK are indicated accordingly.

Vocalisations

Typical vocalisations uttered in HK are indicated usually via reference to www.xeno-canto.org. Where possible, recordings made in HK are used; if this is not possible, then recordings of the appropriate subspecies or of birds as close as possible geographically are provided. Ultimately, however, recordings need to be of sufficient quality to be useful, and this was fundamental to selection.

Distribution & Habitat Preference

An account of these aspects as they relate to HK and any changes over time. Where relevant, reference is made to the breeding bird (1993-96 and 2016-19) and winter atlas (2001-05 and 2016-19) surveys organized by HKBWS.

Occurrence

A description of the pattern of occurrence, including period of presence, strength of migration and peak abundances, that focuses on the period since 1999 in order to be as current as possible. Any changes from the period prior are described where significant. If possible, brief reference is made to the period before 1958, the year when HKBWS began collecting records.

Where possible charts are provided to better illustrate the pattern of occurrence or changes that have occurred. For species that are monitored by systematic counts, data from these was preferred. Thus, the monthly Deep Bay waterbird monitoring programme and seasonal shorebird counts provide the data for these species, while counts of breeding pairs at egretries are used for these birds. Charts illustrating occurrence are provided at the end of the species account before the References.

Breeding

What is known of timing of breeding, location of nests, notable breeding behaviour, brood size, eggs etc, but only if observed in HK. Our knowledge of the ecology of most breeding species in HK is relatively poor and it is hoped that this will stimulate increased interest in this fascinating aspect of bird behaviour.

Behaviour, Foraging & Diet

What is known of characteristic behavioural traits, foraging behaviour and food preferences in HK. As with breeding ecology, relatively little is known about foraging and diet (in particular) and observations are encouraged in the future.

Range & Systematics

HKBWS follows the systematics adopted by the IOC unless there are compelling reasons otherwise (see https://www.worldbirdnames.org/ioc-lists/crossref/). The subspecies occurring in HK have been deduced from this, though in most cases there is no conclusive evidence. The range is usually based on the information provided at Birds of the World (https://birdsoftheworld.org ) supplemented by other references. For China, Liu and Chen (2020) has been adopted as the most up-to-date source, while recognising that much of this is based on the inestimable Cheng (1987).

Conservation Status

For all species this is based on the IUCN assessment made by BirdLife International (2023) and will be updated in line with future assessments. The population trend or the population size is indicated.

References

Provided as a drop-down list.

Recommended Citation

Provided as a drop-down.

Copyright

Copyright of the text resides with Hong Kong Bird Watching Society.

Copyright of the photos remains with the photographers.

Acknowledgements

I would like to acknowledge the contribution of the authors of the species accounts in providing text and the photographers for providing images. I am particularly grateful to the following for providing extra assistance with editing or sourcing photographs, often at short notice: Martin Hale, Paul Leader, Martin Williams, Peter Wong, Dave Bakewell, Sherman Yeung and John Holmes. Finally, a big thank you to Forrest Fong for designing and setting up the website and patiently responding to requests and changes.

References

BirdLife International (2023) IUCN Red List for birds. Downloaded from http://www.birdlife.org

Carey, G. J., M. L. Chalmers, D. A. Diskin, P. R. Kennerley, P. J. Leader, M. R. Leven, R. W. Lewthwaite, D. S. Melville, M. Turnbull and L. Young (2001). The Avifauna of Hong Kong. Hong Kong Bird Watching Society, Hong Kong.

Cheng, T. H. (1987). A Synopsis of the Avifauna of China. Science Press, Beijing.

HKBWS (The Hong Kong Bird Watching Society) (2022). HKBWS Field Guide to the birds of Hong Kong and South China. The Hong Kong Bird Watching Society, Hong Kong.

Liu, Y. and Y. H. Chen (2020). The CNG Field Guide to the Birds of China (in Chinese). Hunan Science and Technology Publication House, Changsha.

Geoff J. Carey

Editor