Bird News from Nial Moores with Jungmoon Ha, and Jung Hanchul and Park Hea-jeong (Hwaseong KFEM).
Outstanding highlights during the third of ten surveys at this premier shorebird site included 30 shorebird species in a day; single Little Stint on 21st; and on 24th, two Gull-billed and 13 Whiskered Terns, an oddly white-faced plover, a flock of wading Red-necked Phalarope and several singing Ochre-rumped Bunting. And we are still in July!
In total, we recorded a minimum 11,237 individual shorebirds within the Flyway Network Site (FNS), including six shorebird species in internationally important concentrations; and ~9,000 shorebirds in the adjacent Asan Bay reclamation area.
A little more on some of these highlights:
- Kentish Plover Charadrius alexandrinus 왕눈물떼새
On 21st, 1,013 were counted at high tide, equivalent to 1% of the population breeding in “Korea, Japan, Ryukyu Island to E & SE China, Taiwan” according to Wetlands International (2020) – incorrectly ascribed to dealbatus but now generally ascribed to nihonensis.
One of these was strikingly white-faced; showed sandy tones to some of the upperparts; and highly unusually, striking white fringes to many of the wing coverts on the closed wing. These are features typically associated with the newly-resurrected White-faced Plover C. dealbatus.
Based on current knowledge, White-faced Plover breeds along the south China coast, with some migrating south into e.g. Thailand and Singapore during the boreal winter. The species is assessed as Data Deficient by BirdLife International (2020), in part because identification criteria for this poorly-known species are still evolving.
In past years, very small numbers of birds that showed multiple features of White-faced Plover have been seen in the ROK; and one or two individuals seen during the second survey and the present survey similarly appear to show multiple features of White-faced Plover. However, it is unclear whether many of these identification features can also be shown (very rarely) by Kentish Plover; or whether they might perhaps be the result of hybridization?
- Far Eastern Curlew Numenius madagascariensis 알락꼬리마도요
The 2,275 counted on July 24th is 7% of the world population of 32,000 of this globally Endangered species estimated by Wetlands International (2020), as assessed in 2012; and 6.5% of the world population of 35,000 as estimated by Hansen et al. (2016).
Two further notable observations of this species included the first juvenile of the year (on 21st) and a small but growing number of individuals (perhaps 5-10% of birds which are present) showing gaps in the inner primaries, i.e. starting primary moult.
- Red Knot Calidris canutus 붉은가슴도요
One breeding-plumaged adult on 21st.
- Broad-billed Sandpiper Calidris falcinellus 송곳부리도요
Among the small number of adults seen, extraordinary was a juvenile seen on 24th. Broad-billed Sandpiper typically peaks late in May during northward migration (e.g. Moores et al. 2016); juveniles are not usually seen in the Republic of Korea (ROK) until mid or late August (pers obs.); and in the west of the range, in one study area juveniles only reached the 54th parallel in August (Meissner 2005). Even more remarkable, however, SBS in China researcher Zhang Lin reported finding a juvenile on or before July 8th 2020 on the Jiangsu coast…what were the conditions on the breeding grounds for this species in this Siberian heatwave summer?
- Sharp-tailed Sandpiper Calidris acuminata 메추라기도요
The first four of the autumn were in the reclamation lake on 24th.
- Red-necked Stint Calidris ruficollis 좀도요
On 24th, 1,130 were counted within the FNS, and an estimated 3,000 were present within the Asan Bay main reclamation area.
- Little Stint Calidris minuta 작은도요
An adult was seen (and poorly photographed) foraging with Red-necked Stints at Maehyangri on July 21st. Identification was based on structure (very attenuated looking, with a smaller “booble head”, a longer, fine-tipped bill and longer legs in direct comparison with many Red-necked Stints) and plumage (with several very black-centred greater coverts, especially on the right side of the bird; and strong rust fringes to the tertials etc). Before 2010, the species was considered to be extremely rare in the ROK. However, the species is now known to occur in very small numbers annually during migration.
- Red-necked Phalarope Phalaropus lobatus 지느러미발도요
Much more often seen in distant flocks moving over or resting on the sea, it was wonderful on 24th to watch a group of 45 step up out of the water, and run across the mud mixed along with hundreds of stints and Dunlin!
- Gull-billed Tern Gelochelidon nilotica 큰부리제비갈매기
Two medium-sized, black-capped white terns without tail streamers were seen flying over the Hwaseong Reclamation Lake on July 24th. Gull-billed Tern is the only tern in Korea showing such features. Although likely occurring annually in the ROK in small numbers, the species is perhaps not reported annually and there is only one previous record nationwide of the species currently listed on eBird.
- Whiskered Tern Chlidonias hybrida 구레나룻제비갈매기
On 24th, a flock of 12 were seen at Maehwari (a very high count for the ROK) and one was in a water treatment pond in the FNS. This species is considered to be a rare migrant through the ROK.
- Black-faced Spoonbill Platalea minor 저어새
143 counted on July 21st is more than 7% of the total population estimated by Wetlands International (2020), based on a 2012 estimate; and is 2.9% of the total of 4,864 recorded by the 2020 international winter census of the species (EAAFP 2020).
- Ochre-rumped Bunting Emberiza yessoensis 쇠검은머리쑥새
On July 21st, HJM sound-recorded two distant singing buntings which he tentatively identified as Ochre-rumped Bunting, a globally Near Threatened species which is known to breed at only two others sites on the Korean Peninsula: in Shihwa Lake in the ROK and the Rason Ramsar site in the DPRK. On July 24th, two hours were spent searching areas of suitable habitat (non-reed grassland) and approximately 1km to the south at least four singing birds were heard, and probably four different males and one female seen. The area contains several patches of grassland which still have not yet been surveyed during the project, suggesting that more territories of this species might be present within the Hwaseong FNS.
A much more detailed report has already been written and shared with the EAAFP Secretariat. If any Birds Korea members would like to receive a copy of this or of any other survey report, please let us know!