IDENTIFICATION

VOCALISATIONS

The song is a low-pitched, rolling and somewhat rhythmic cooing.

DISTRIBUTION & HABITAT PREFERENCE

Rock Dove, or Feral Pigeon as it is otherwise known, is entirely restricted to anthropogenic habitats and is largely found in the core urban areas of HK Island and Kowloon, together with the centres of the New Towns, especially Yuen Long and Tuen Mun. Smaller numbers may be found around fish pond culture areas and in villages, although some of the latter may be better regarded as free-living livestock rather than their being truly feral. Rock Dove is largely absent from the islands, though comparison of the atlas surveys, which show just small numbers in Mui Wo and Tung Chung on Lantau and none elsewhere, with eBird (2021) suggest that the former understate the true extent of occurrence.

Distribution appears to have changed little between the 1993-96 breeding atlas survey, when Rock Dove was recorded in 10.8% of squares, and the 2016-19 surveys when it was recorded in 9.0% of squares in summer and 8.9% of squares in winter; that it was only recorded in 5.2.% of squares in the 2001-05 winter atlas survey is undoubtedly an artefact of lack of observer coverage, as the map shows it as being almost entirely absent from Tsuen Wan, Kowloon and HK Island which is not credible.

HK is far from the native range of Rock Dove and the local population has undoubtedly been introduced by people. Rock Doves have long been kept in China, often in free flying conditions, and it seems likely that feral Rock Doves may have been here for hundreds of years. However, this is not known for certain; like most birdwatchers today, past chroniclers of the avifauna, up to and including Chalmers (1986), seem to have ignored Rock Dove, and its first appearance in the literature appears to come from Webster and Phillipps (1976) who stated that domestic pigeons were common in the city, and Viney and Phillipps (1977) who noted that compared to other cities there were very few feral pigeons in HK, but that flocks of domestic pigeons were commonly seen. These flocks of domestic pigeons were doubtless being kept for food, a practice that has now largely been stopped in HK in order to minimise the risk of spread of avian influenza; however, Rock Doves found today in some village areas are perhaps descended from such birds.

Subsequently, Carey et al. (2001) also suggested that urban areas supported fewer Rock Doves than might be expected and opined that this might be related to the abundance of Spotted Dove. However, do these species compete to a significant extent? Whilst in urban areas both species probably eat similar food and find much of their food on the ground, other aspects of their ecology are rather different. Spotted Doves rarely occur or forage in flocks, whilst Rock Dove is highly social and occurs in marked concentrations at food sources. Similarily, whilst it will use artificial nest sites, Spotted Dove largely builds solitary nests in trees, whilst Rock Dove is highly colonial, nesting in cavities or other sheltered sites in buildings or other structures, with the void behind external air-conditioning units being particularly favoured.

OCCURRENCE 

Feral Rock Dove populations in HK appear to be entirely sedentary. However, lost racing pigeons, many of which carry rings from Taiwan, are not infrequent on Po Toi and at Mai Po and may also account for occasional observations from other sites far from suitable habitat and regular haunts.

Rock Dove regularly occurs in flocks, especially in city parks. High counts include 231 in Victoria Park on 21 July 2016, 323 (the highest count) at Hang Hau on 31 January 2017, 219 at Tai Wo on 17 February 2017, 169 in Kowloon Park on 16 October 2019 and 201 in Tsim Sha Tsui on 23 December 2020.

BEHAVIOUR, FORAGING & DIET

Rock Dove is typically seen foraging on the ground in parks or even in busy city streets, or roosting or loafing on buildings or other structures. On the latter, ledges or other sheltered locations where birds can congregate are often selected, in contrast to the more solitary Spotted Dove which often selects a site such as a lamp standard with space for only a single individual or a pair of birds. Rock Dove does perch in trees, especially in city parks, but usually only uses large stable branches – in its natural range Rock Dove perches almost entirely on rocks and presumably this adaptation is reflected in the structure and musculature of the tarsi and toes making it difficult or impossible for Rock Doves to grasp narrow branches.

Rock Dove is probably largely dependent on food provided by people, whether accidentally or deliberately. In the urban area Rock Doves frequently congregate where food waste is spilt and whilst deliberate feeding of birds in city parks is not officially permitted, this often occurs, with this species being one of the main beneficiaries. In more rural situations Rock Doves often forage around fish ponds where bread or noodles intended as fish food is stored or spilt, whilst rice is readily eaten in the few locations such as Long Valley, where it is still grown. Presumably natural food, such as grass seeds and fruit is also eaten, but observations are lacking, an information gap that could readily be filled by a birdwatcher spending a lunch hour in a city park.

BREEDING

In HK, Rock Dove is wholly dependent on artificial structures to provide breeding sites. Nests are located under overhangs or in cavities in buildings, with soffit voids under viaducts being particularly favoured, and are often apparently occupied by a number of pairs. Such locations are almost inaccessible to observers and very difficult to see into; furthermore, nest sites are apparently often occupied throughout the year. Perhaps for this reason, together with a general lack of interest in this species, nothing is known about the timing of breeding, breeding colony size, number of broods raised or other aspects of breeding ecology in HK.

RANGE & SYSTEMATICS

As a wild bird, Rock Dove has a wide range in the southern part of western Palearctic (extending marginally into the northern Afrotropics) and the Oriental Region, where it occurs throughout the Indian subcontinent east to Bangladesh. The central Asian distribution extends into western Xinjiang Province and north to Mongolia.

As a feral species it occurs almost worldwide as a commensal with man, but the true distribution of self-supporting populations is rather poorly documented as ‘Feral Pigeon’ tends to be ignored by both scientific ornithologists and birdwatchers. In China feral birds appear to be present in most of the cities and larger towns throughout the country, including Xinjiang where, presumably, significant introgression between ‘C. l. domestica’ and ‘wild’ C. l. livia must be taking place.

There are nine subspecies recognised by IOC which does not allocate feral populations to a taxon. Whilst not recognised by IOC, some authorities use the epithet C. l. domestica for feral populations.

CONSERVATION STATUS

IUCN: Least Concern. Wild population trend decreasing.