IDENTIFICATION

VOCALISATIONS

A slightly nasal, inflected note is uttered quietly by foraging birds.

The song is a nasal rattle preceded by a one or two call notes.

DISTRIBUTION & HABITAT PREFERENCE

Red-rumped Swallows forage over fish ponds, marshes, agricultural land and wooded hillsides. Most reports are from the Deep Bay area and rural parts of the New Territories. There are relatively few records from Lantau and other offshore islands, and it is rather rare even on Po Toi, where there were only 15 records from 2001 to 2020. There were no records from HK Island or Kowloon in that time.

There was no change in the winter distribution as recorded by the winter atlas surveys of 2001-05 and 2016-19 when it occurred in 0.4% and 0.5% of 1 km squares, mostly in the Deep Bay area.

OCCURRENCE

Red-rumped Swallow is recorded all year, with highest numbers occurring from the second week of November to the end of the year (Figure 1). It seems that most of these birds pass through, as after the turn of the year numbers are significantly lower. Usually no more than 40 are reported, though the highest count since 1999 is 282 on 7 December 2012. Unusually large numbers were recorded in December 1982, including 350 in the Starling Inlet area on 8th, the highest count to date, and up to 220 in the Mai Po-San Tin area during 12th-18th.

Numbers then decline slowly to a minimum around the end of February and beginning of March, after which a weak spring passage is evident that peaks in April and continues until mid-May. In spring, most reports refer to flocks of up to ten, occasionally more, the peak count being 60 over fish ponds at Mai Po on 9 April 1993 and 22 March 1998.

Up to 1998 Red-rumped Swallow was only recorded from the middle of September to the third week of May. However, since 2001 it has been recorded annually in the summer months, and the first breeding record occurred in 2003.

Vaughan and Jones (1913) found it nesting in western Guangdong, but it was not recorded in HK until 1932 (Herklots 1935). Subsequently, it was noted in spring in the 1930s (Herklots 1953) and in spring and autumn in the 1950s (Dove and Goodhart 1955, Walker 1958).

BREEDING

The first breeding record occurred in 2003 in Shui Mei Village, Kam Tin (Allcock 2009). The number of breeding pairs has remained low, however, with generally only one or two pairs at each site (four nests, two of which were occupied, were at Kam Tin on 1 June 2009). Kam Tin and Mai Po Village remain the only areas in which breeding has been proven.

Collection of mud for nesting has been noted from 29 November to 29 February, and again on 3 June, copulation on 24 February, active nests from at least 23 March to 1 July and up to three dependent young from 12 May to 6 August.

BEHAVIOUR, FORAGING & DIET

Small loose flocks are often encountered foraging over fish pond areas, with their distinctive though rather quiet call often the first sign. It is an aerial insectivore but no details.

RANGE & SYSTEMATICS

Breeds from southern Europe and northwest Africa east through southeast Europe to Iran, the Indian subcontinent, and from northeast Kazakhstan to Japan and south China; also, east Africa. Winters south to south Africa, southern parts of the Indian subcontinent, southwest and southeast Asia (Taylor and Kirwan 2020). In China, a summer visitor to much of the country south of a line from southeast Tibet to Heilongjiang except the coastal provinces of southeast China, where it is a winter visitor (Liu and Chen 2020).

Polytypic, with the taxon occurring in HK being C. d. japonica, which breeds from southeast Siberia to Japan and south China. The nominate form breeds from northeast Kazakhstan and Mongolia to south central China, while the remaining subspecies occur in the rest of its Asian, European and African range.

CONSERVATION STATUS

IUCN: Least Concern. Population trend stable.