Nakdong Estuary and Geum Estuary, September 26 – 28

Bird News from the Birds Korea “Long Weekend” by Nial Moores, with Andreas Kim, Robin Newlin, Ha Jung Mun, Jason Loghry, Patrick Blake and Park Jin-Seok

A “marathon” 3-day weekend (preceded by an afternoon of birding in Igidae in Busan on the 25^th) saw multiple Birds Korea objectives met and provided opportunities for information-sharing and survey work focused on the Critically Endangered Spoon-billed Sandpiper and other threatened waterbirds. This post is focused simply on notable bird observations (in the hope that others will write at greater length in separate posts about the seminar, kindly supported financially by K Water; and also about our latest report, “Status of Birds, 2014”).

Due to a rather tight / hectic schedule, observations below were made in two hours in Igidae on the 25^th (by NM and Andreas Kim); during nine hours of fieldwork at the Nakdong Estuary on the 26^th (NM, AK and Robin Newlin); during four hours of educational program at the Nakdong Estuary on the 27^th; and during 13 hours on Yubu Island, Geum Estuary, on the 28^th (NM, RN, Jason Loghry, Ha Jung Mun and Patrick Blake), when very large numbers of shorebirds were counted during both the early morning high tide and the especially good evening high tide.

Most notable species included:

Swan Goose Anser cygnoides. Three were at Yubu on the 28^th.
Common Shelduck Tadorna tadorna. Three were in the Nakdong Estuary on the 27^th.
Falcated Duck Anas falcata. Probably 20+ were in the Nakdong Estuary on the 27^th, mixed in with high hundreds of other duck.
Black-faced Spoonbill Platalea minor. Four were in the Nakdong Estuary on the 26^th, with 1-2 there on the 27^th; and one was on Yubu on the 28^th.
Chinese Egret Egretta eulophotes. Two or three were in the Nakdong Estuary on the 26^th and 27^th and probably 10+ were on Yubu on the 28^th.

Chinese Egret Egretta eulophotes, © Jason Loghry

Black Kite Milvus migrans. One was in Igidae on the 25^th and perhaps 15, all of which were juveniles, were in the Nakdong Estuary on the 26^th and 27^th.

Black Kite Milvus migrans, © Robin Newlin

Black Kite Milvus migrans, © Andreas Kim

Far Eastern Oystercatcher Haematopus (ostralegus) osculans. Seven were in the Nakdong Estuary on the 26^th and 27^th. At least 4,500 were counted in 45 “blocks of 100” from Yubu on the 28^th.
Pacific Golden Plover Pluvialis fulva. Perhaps up to 10 were in the Nakdong Estuary on the 26^th; and one was at Yubu on the 28^th.

Pacific Golden Plover Pluvialis fulva, © Andreas Kim

Grey Plover Pluvialis squatarola. Twenty to thirty were in the Nakdong Estuary on the 26^th (including many juveniles) and only c. 300 were on Yubu on the 28^th. In autumn 2007, counts on Yubu on August 16^th-17^th, September 12^th and September 28^th all found much higher counts of this species, with 2,100 there on September 28^th 2007 (SSMP 2007 report).
Kentish Plover Charadrius alexandrinus. Probably 200 were in the Nakdong Estuary on the 26^th and 150 on the 27^th. On Yubu on the 28th, 11,000 were counted in one scan of the closer smaller shorebirds, with a total of 15,000 estimated (out of a total 41,800 smaller shorebirds counted an hour or so before high tide). This is a remarkably high count of this fast-declining species, Red-Listed by Birds Korea.
White-faced Plover Charadrius. alexandrinus dealbatus (?). A taxon now split at the species-level by BirdLife International, though regrettably on apparently incorrect ID criteria. On Yubu on the 28^th, four or so plovers were obviously (slightly) larger, much heavier-billed and longer-legged, with paler sandy upperparts than typical (presumed nihonensis) Kentish, and all such birds also had pink or pinky-yellow leg colour (when all obvious Kentish were either mostly grey or green-grey legged). These individuals, all seen in the same area as c.30 (now only suspected) White-faced Plover seen last year, recalled Greater Sand or Mongolian Plover at some angles more than Kentish, and at least two were very aggressive towards typical-looking Kentish, driving them away from temporary feeding territories (using a deeper “churritt” call than typical Kentish). Two or three of these had white lores on one or both sides of the head; the best seen individual (with the camera set to darken the images considerably) had extensive dark on the lores on one side and faint brown on the other. Pale at the bill base was looked for in all of these birds but not seen, though conditions were extremely bright. As this bird in the images had large breast patches and no pink at the bill base it was thought possibly to be a Kentish but….might it instead have been White-faced? Correspondence with Jonathan Martinez, who has much experience of breeding and non-breeding “Swinhoe’s Plover” (the perhaps better name for dealbatus, as it is often has marked lores in non-breeding plumage), throws up the possibility that some birds in the ROK might show intermediate characters between “true dealbatus” and “true nihonensis”. Several images of breeding Kentish Plover from the southwest of the country in our gallery, for example, show some pink on the legs (said to be a feature of dealbatus) but otherwise look like typical Kentish. It is clear that much more work is needed still to resolve the status of the various Kentish-type taxa!

White-faced Plover Charadrius alexandrinus dealbatus (?), © Nial Moores

Mongolian Plover Charadrius mongolus. Only sixty or so at the Nakdong Estuary on the 26^th and 27^th but an estimated 3,000 at Yubu on the 28^th.

Mongolian Plover Charadrius mongolus, © Nial Moores

Greater Sand Plover Charadrius leschenaultii. One or two at the Nakdong Estuary on the 26^th and three at the Geum Estuary on the 28^th.
Eurasian Curlew Numenius arquata. At least 130 were in the Nakdong Estuary on the 26^th and an estimated 2,300 were at Yubu on the 28^th, with many of these “appearing” shortly before high tide.
Far Eastern Curlew Numenius madagascariensis. At least 90 were at the Nakdong Estuary on the 26^th, though only ~2 were seen there on the 27^th. On the 28th, an estimated 2,200 were on Yubu. Many of these “appeared” about an hour before highest tide, and “disappeared” 15 minutes later.

Far Eastern Curlew Numenius madagascariensis, © Robin Newlin

Nordmann’s Greenshank Tringa guttifer. Five were seen in one scan on Yubu on the 28^th, and several others (the same, or an additional 3-4 individuals) were seen at other times of the day.
Great Knot Calidris tenuirostris. Sixty-five were in the Nakdong Estuary on the 26^th and 2,000 were counted in repeated scans along the shoreline at Yubu on the 28^th.
Red Knot Calidris canutus. Five were in the Great Knot flock at the Nakdong Estuary on the 26^th and probably 20 were seen at Yubu on the 28^th.
Sanderling Calidris alba. Probably 300-400 were at the Nakdong Estuary on the 26^th, and c.500 were at Yubu on the 28^th.

Sanderling Calidris alba, © Robin Newlin

Red-necked Stint Calidris ruficollis. Only 50-100 were seen in the Nakdong Estuary on the 26^th (compared with 1500 at the same time last year). At Yubu, there were probably 1,000 present shortly before high-tide. The rather low numbers suggest that the breeding success of the population moving through the ROK might have been lower than last year, when exceptionally good numbers of juveniles were seen. At least one leg-flagged bird was seen, with black over yellow on the right leg (banded in SW Kamchatka in late August this year per Evgeny Syroechkovskiy).

Red-necked Stint Calidris ruficollis, © Robin Newlin

Little Stint Calidris minuta. Based on structure, one worn juvenile was at the Nakdong Estuary on the 26^th. A possible (appearing long-billed, strongly marked on the head, rufous and black with decent white braces) was also seen briefly and poorly digiscoped on Yubu on 28^th (NM only).
Curlew Sandpiper Calidris ferruginea. One was on Yubu on the 28^th.
Dunlin Calidris alpina. About 50 were in the Nakdong Estuary on the 26^th and >20,000 were at Yubu on the 28^th. One of these was flagged black over yellow (so was banded in SW Kamchatka); another was banded engraved white over blue on the left leg (digiscoped by JL); one had a single orange flag on the right leg; and one had white over orange and another orange over white on the right leg (so both had been banded in the ROK, one more recently than the other).

Dunlin Calidris alpina, © Andreas Kim

Spoon-billed Sandpiper Eurynorhynchus pygmeus. A total of four or five juveniles were seen in the Nakdong Estuary on the 26^th, with three seen in one scan there on the 27^th (with much less coverage). None had leg-flags. At Yubu on the 28^th, nine were counted in a single scan along the western edge on the falling tide (in amongst probably <30% of the 41,800 small shorebirds counted in blocks of 100 two hours before high tide). There were several additional encounters with birds on other parts of the flats before and after this, so an estimated 11 were recorded during the day. Of these three had flags. One Juvenile into First-winter was banded black over yellow (so was one of five juveniles banded in SW Kamchatka in late August by Birds Russia) and two, aged as adults, carried light green flags. One of these flags appeared to be engraved (with a “3” or some such) though was only seen distantly. The least bad image of this bird and flag has been sent onto Nigel Clark at the BTO to try to decipher. Further survey is still required through all tide states to see if there are any more patches of habitat in the Geum Estuary preferred by spoonies that are not usually counted.

Spoon-billed Sandpiper Eurynorhynchus pygmeus, Nakdong Estuary, © Andreas Kim

Spoon-billed Sandpiper Eurynorhynchus pygmeus, Nakdong Estuary, © Robin Newlin

Spoon-billed Sandpiper Eurynorhynchus pygmeus, Yubu Island, black over yellow flag, © Jason Loghry

Broad-billed Sandpiper Limicola falcinellus. Probably 5-10 were at the Nakdong Estuary on the 26^th and 1,000-1,500 were at Yubu on the 28^th.

Saunders’s Gull Chroicocephalus saundersi. At least 15 were at Yubu on the 28^th.
Relict Gull Ichthyaetus relictus. Two First-winters were seen together in the Nakdong Estuary on the 26^th; only one remained there on the 27^th. This is likely to be the first September record of this species in the ROK (perhaps, hopefully, the result of a successful breeding season for the Russian population?).

Vega Gull Larus vegae. At least 18 were in the Nakdong Estuary on the 26^th (the first seen in Busan this autumn by NM was on September 18^th).
Taimyr Gull Larus heuglini taimyrensis. At least 24 were in the Nakdong Estuary on the 26^th and 2-3 on Yubu on the 28^th.
Gull-billed Tern Gelochelidon nilotica. One in non-breeding plumage (perhaps a First Winter) was found and photographed in the Nakdong Estuary on the 26^th. It apparently took a dragonfly before then taking crabs – dropping from several meters up in swoops like an exaggerated Saunders’s Gull. This species is scarcely annually-recorded in the ROK.

Common Tern Sterna hirundo. Five or more were seen moving south off Igidae on the 25^th and at least 80 were in or offshore from the Nakdong Estuary on the 26^th, with none were seen there on the 27^th.
Pomarine Skua Stercorarius pomarinus. One was seen flying south off Igidae on the 25^th.
Richard’s Pipit Anthus richardi. At least 15 were in the Nakdong Estuary on the 26^th, with three there on the 27^th. One was heard over Yubu on the 28^th.
Blyth’s Pipit Anthus godlewskii. One First Calendar-year was heard and seen in the Nakdong Estuary on the 27^th.
Olive-backed Pipit Anthus hodgsoni. Probably 10-15 were heard over Yubu during the 28^th, marking the start of autumn migration of this species.
Pechora Pipit Anthus gustavi. At least six were in the Nakdong Estuary on the 26^th, with 2+ there on the 27^th and perhaps 5-10 overflying Yubu during the 28^th.
Red-throated Pipit Anthus cervinus. One was in the Nakdong Estuary on the 26^th and probably 20-30 were heard overflying Yubu on the 28^th, marking the start of autumn migration of this species.

Leave a Reply Cancel reply

Tags