southern waters

It is only relatively recently that people have become aware of the movement of seabirds through Hong Kong coastal waters in spring. The first records of Short-tailed Shearwater and Streaked Shearwater, for example, were not until 2004 and 2005 respectively. Such records have prompted birders to explore further and there are now regular privately-arranged excursions offshore in April and early May. This spring I was fortunate enough to go out on two of these trips on 28 April and 12 May, and the following images are from those outings.

Aleutian Terns on flotsam, southern waters, 28 April 2018

Aleutian Terns on flotsam, southern waters, 28 April 2018

Aleutian Tern in flight, southern waters, 28 April 2018

Aleutian Terns were first recorded in Hong Kong in 1992, presumably having been passed off as Common Terns prior to that date. It breeds in eastern Russia and Alaska; winter sightings have come from Malaysia, Indonesia and the Philippines south to Australia. It is a regular passage migrant through Hong Kong waters, with the extreme dates on spring migration being 5 April to 7 June,  and in autumn 2 August to 29 October. The highest count is of 865 from Cape D'Aguilar on 2 May 1999 during the passage of Typhoon Leo. The peak count in recent years is of 430 flying south off Po Toi on 9 September  2010.

Bridled Tern in flight, Po Toi rock, 12 May 2018

Bridled Terns in flight, Po Toi rock, 12 May 2018

Bridled Terns are passage migrants and summer visitors to Hong Kong. They breed in Mirs Bay and on Po Toi rock. They have been recorded between 12 April and 15 October and the highest count is 749 on 25 September 1993 during Typhoon Dot. The highest count of breeding birds in Mirs Bay is of 650 in summer 2004.

Pomarine Skua in flight, southern waters, 28 April 2018

The Pomarine Skua is a scarce & irregular spring migrant though offshore waters, with occasional autumn sightings (usually during typhoons). It has been noted between  10 February and 16 May, and between 26 September and 5 November. The highest count is 47 on 16 Oct 1998 during Typhoon Babs. It was recorded in only seven years from 2000 to 2015, with a peak count of ten on 10 March 2007. It breeds on the tundra of north Russia, north Alaska and north Canada, and  winters at sea close to coasts, mainly between the Tropic of Cancer and the equator, and around Australia.

Short-tailed Shearwater, southern waters, 12 May 2018

Short-tailed Shearwater, southern waters, 12 May 2018

The Short-tailed Shearwater breeds in southern Australia during the austral summer. Post-breeding, the majority of the population appears to carry out a circular trans-equatorial movement to the north Pacific (May – September) with birds occurring off Japan in June, the Bering Sea in July, and the central Pacific in August. In Hong Kong they are regular in small numbers in spring in southern waters between 20 April and 3 June, with most occurring in the first two weeks of May. The highest count is 15 on 14 May 2007.

With special thanks to Carrie Ma.