Following ground-breaking shorebird survey work on the Korean west coast in 1988 by a joint team of East Anglia University and Kyung Hee University bird researchers, Colin Poole and Mark Eldridge (both of who had been in the 1988 survey), the author and GM Cresswell visited Jeju Island to look at migration.

The Southern Yellow Sea, where Jeju is located, has been effectively an unknown region for migration until very recently, and its potential was almost completely unknown in the early-mid 1990s. This is despite international interest in Beidaihe, and more recently Happy Island, in the north of the Yellow Sea, and the fame amongst Japanese birdwatchers of Tshushima Island (Teima Do in Korean) several hundred km to the east. This 1993 visit to Jeju was followed by a repeat visit by AS and SC Joyner in 1994.

The observations contained in this summary report were conducted at the following sites:-

Mosulpo (also known as Taejeong)

Situated at the South West corner of Jeju Do (at approximately 33° 12'N, 126° 13''E) a small fishing town with a harbour which drains to mud at low tide: most famous for being the location of the wrecking of Hendrick Hamel in 1653.

Yakpo

A headland immediately outside Mosulpo, consisting of open barley and cabbage fields, a thin wood of pine trees, a small area of mixed woodland, an area of open grassland (a disused airstrip originally built by the Japanese in the 1930s) and rocky shore interspersed with sandy beach.

Kapa Do (Gapa Do or Island)

A small island, about a mile offshore from Mosulpo, very flat and covered in barley fields with minimal cover other than a few trees around the island school and a small tree-filled garden. Apart from the nearby islet of Mara Do, this is the most southerly point in Korea.

All sites are easily covered on foot from yogwan accommodation in Mosulpo, the island being reached by a daily ferry, weather permitting.

* Mainland shorebird sites (Namyang Bay/Asan Bay and Ganghwa Island) were also visited in 1993, with most exceptional being 25 Nordmann's Greenshank at Namyang on 11th May.

General Observations on Weather

On both visits the weather was extremely maritime in nature, characterised by fast-moving depressions arriving from the west and passing either to the north of Jeju, thereby producing westerly winds, or (more frequently) to the south, producing winds with an easterly component. This pattern was strangely reminiscent of Western Britain and resulted in very frequent changes of weather, with strong winds and rain alternating rapidly with bright, calm and sunny spells.

In 1993 there were two periods of particularly violent gales from the south east, whilst in 1994, the most violent weather experienced was a day of utterly torrential rain.

General Character of Migration and the Influence of Weather

It became obvious over the two visits that this was not a site where vast falls of birds takes place. This was however compensated for by a great species diversity and a very rapid turnover of birds. Individual migrants rarely stayed for long and each day brought a new and distinctive mix of new birds.

This species mix was particularly interesting, containing both western (mainland Asian) and eastern (Japanese) elements.

Indeed there was a very noticeable correlation between the weather/wind situation and the species mix of the arrivals. On days with a westerly airflow, there would be larger and more varied arrivals (presumably originating from the Chinese coast) with noticeably higher numbers of buntings and Yellow-browed Warblers, along with, for example, the odd Radde's or Dusky Warbler. Days with an easterly airflow were characterised by smaller numbers of birds and a reduced species diversity. Birds typically prominent in these conditions were Siberian Blue Robin, xanthodryas Arctic Warbler, Narcissus Flycatcher and davisoni Siberian Thrush, presumably originating from somewhere along the southern chain of Japanese islands.

These categories were not however 'watertight', as 'eastern' species were likely to be encountered (albeit in smaller numbers) on 'westerly days' and vice versa. In addition some birds (e.g. Yellow-rumped Flycatcher and Eastern Crowned Warbler) showed little weather correlation at all. Some of this must be attributable to the fact that such birds are either heading to South Korea anyway or intend to pass through or over-fly the region en route to somewhere else. It was not therefore always clear to what extent birds were actually being displaced from a preferred course of direction.

Interestingly, there was little direct correlation between rainfall (what might be termed in a British context 'fall conditions') and arrivals of birds. The largest arrival in 1993 did indeed take place in rain but in general rainfall did not produce falls and was often characterised by low numbers of birds (somewhat similar to Gageo approximately 150km to the Northwest, but unlike Eocheong island 250 km to the north: NM). A clear pattern soon emerged of the strongest arrivals taking place in bright clear conditions with a light wind from a westerly quarter. The largest and most varied arrivals could invariably be expected on such days and these would usually alternate on a 2-3 day cycle with days of southeasterly wind and rain (and correspondingly fewer, though different, birds).

Arrivals of birds would typically take place through the day, most obviously of course with diurnal migrants such as Pacific Swifts and Red-rumped Swallows, but even small passerines (e.g. Brown Flycatcher and Arctic Warbler) would be commonly seen approaching land low over the sea at all times of the day.

As is typical in Britain in Spring, there was a rapid change in the species mix according to the date as well as the weather. For example birds such as Eastern Crowned Warblers were largely gone by10th-15th May, being replaced as the month progressed as the commonest phylloscopus by Arctic Warbler. Other 'late species' included Siberian Flycatcher, Black-browed Reed Warbler and Pallas's and Middendorff's Grasshopper Warblers. Similarly, the trips recorded only singles of Dusky Thrush, Red-flanked Bluetail and Siberian Stonechat and no Hoopoes at all – typically species which are now known to peak rather earlier in the spring.

Species Status

At the time of the visits we had very little idea of the status of the birds, other than some clues in e.g. Won and Gore (1971) and a couple of Korean photographic guides (in Korean).

Some of the more interesting observations are listed below (with annotation by NM):

• 6 Chinese Egrets .
  Classified as Vulnerable, this species is near-confined to the Yellow Sea as a nesting species, with the majority of known pairs in the Gyeonggi Bay region. It is regular in small numbers in spring on offshore islands, with a broader southward dispersal along the west coast in August and September.

• Schrenck's Little Bittern .
  Shrenck's Bittern, now classified as Lower Risk, have declined significantly in South Korea and Japan as nesting species. They are, however, surprisingly regular in very small numbers as migrants in spring on offshore islands.

• Up to 10,000 Red-necked Phalaropes (peak 10 000 + April 26, 1993, Mosulpo)
  Until recently (pre-1995) abundant on northward migration, this species has undergone a massive decline in north-east Asia, with peak counts of over 100 000 in Tokyo Bay being reduced to several hundreds in recent years. The 1993 and 1994 Jeju counts were similar to counts in Fukuoka and Nagasaki Prefecture, southwest Japan, made by NM, especially in 1991 and 1992. It would be particularly interesting to discover if similarly high numbers have been recorded in subsequent years near Jeju.

• Small parties of Oriental Pratincoles , perhaps adding up to around 40
  Described as a rare migrant in Lee, Koo and Park (2000), the Oriental Pratincole is a scarce migrant through western, and especially southwestern Korea. These are perhaps birds destined for nesting colonies in Japan (with sporadic nesting from Fukuoka Prefecture in the southwest, eastward to the Kanto Plain). The counts in 1993 and 1994 are significantly higher than any subsequent ones known elsewhere from Korea.

• 2 Whiskered Terns
  Increasingly recorded in South Korea, these are amongst or are the very first records of the species in Korea.

• 2 Chinese Pond Herons
  Increasingly recorded in South Korea, especially along the west coast, with nesting first recorded in the Gimpo area in the late 1990s. A migration peak of 9-12 on Gageo Island was recorded in spring 2000 (NM).

• White-breasted Waterhen
  Increasingly recorded in South Korea, especially during migration on the west coast, with nesting first suspected in 2000.

• Grey-headed Lapwing
  Classified as Low Risk, this species is barely recorded annually in South Korea, interestingly with records of single birds on Gageo Island (Park Jin Young) and Eocheong Island (NM) in May 2002. The species is rather commoner in Japan, and though scarce on the southwest main island of Kyushu, it nested in Fukuoka Prefecture through the 1990s, also occurring in very small numbers southward in winter.

• 4 Greater Sand Plover
  Although rather scarce in Korea, this species occurs regularly in the Saemankeum area and especially in the Nakdong estuary.

• A flock of 20 Little Whimbrel
  A very scarce migrant to Korea, most records come from the southwest and west, especially from islands. The flock of 20 on April 29th 1993 is presumably the largest flock known for South Korea.

• A flock of 80 Pacific Golden Plover
  Although relatively uncommon, Pacific Golden Plovers are widespread in small groups on migration, being especially associated with inclement weather. The flock of 80 is quite possibly the second largest flock recorded in South Korea. Interestingly, the species is much commoner on the eastern side of Japan than in the west or in Korea, strongly suggesting a more easterly bias to its migrations.

• Black-winged Stilt
  Until recently considered very scarce in South Korea, the species is actually a regular migrant along both the south and west coasts, even nesting in Seosan (first discovered in the late 1990s). It has been increasing in Japan too, with nesting regular in Tokyo Bay.

• Greater Short-toed Lark
  Considered a rare vagrant with very few records, the species is clearly overlooked and most probably confused with Asian Short-toed Lark. A peak of 6+ has been recorded on Gageo Island (Kim Su-Kyung and NM, April 14, 2001).

• 7 Grey Thrushes
  Considered a rare vagrant, the records in 1993 and 1994 were amongst the first ever of the species in Korea. Subsequently found to be rather regular, especially in late April-early May, with records from several offshore islands and also the southeastern mainland.

• Frequent Brown Thrushes
  Lee, Koo and Park (2000) give the status of Brown Thrush as a very rare vagrant (with only 6 records), even though its wintering range includes southern China and it nests in Japan. The records in 1993 and 1994 are perhaps the first hinting at the true status of the species in Korea: a not uncommon, but rather local, migrant, most numerous in late April-early May (subsequent peaks include ca 150 in off the sea in 2 hours at Gageo Island in 2001: CAM and NM).

• 2 White-throated Rock Thrushes
  A rare migrant to Korea, the species occurs regularly in small numbers on southwest islands, typically arriving form the second week of May onwards.

• Bluethroat
  Considered to be very rare in Korea, it has recently been shown to be a regular migrant in small numbers, with a few even over-wintering in reedbeds.

• 20 Middendorff's Grasshopper Warblers
  A common migrant, peaking in spring towards the end of May, the day count of 19 is still exceptional.

• 2 Pallas's Grasshopper Warblers
  This species is now known to be a scarce or uncommon migrant through Korea, best found on outer islands in mid-late May.

• 2 Taiga Flycatchers
  The Taiga Flycatcher is a surprisingly scarce though regular migrant through South Korea, apparently in both spring and autumn.

• 3 Little Swifts
  These constitute the first records for South Korea. Subsequently, the species has been recorded several times on other southwest islands in spring, with one record in autumn (NM), suggesting limited but regular migration through southwest Korea. As documented in Brazil's Birds of Japan , the species has shown an increase in recent decades in Japan, and although many appear to be resident in Kyushu, it is likely that there is also a limited movement of birds between Japan and the Okinawan islands, or as these records suggest, into China through Korea.

• Grey-backed Starling
  Although lacking photographic documentation, this surely constitutes the second known record of this distinctive species for Korea (The third record and fourth records, July 1998 and May 2002 [Park Jin-Young], also came from Jeollanam Province in the far southwest).

• 6 Radde's Warblers and 7 Dusky Warblers
  The 1993 and 1994 records are presumably the first series to suggest the true status of these species in Korea: uncommon migrants.

• A presumed Asian Paradise Flycatcher
  Presumably this is the first record for South Korea. No subsequent records for the South, but not surprisingly recorded in the North.

• 2 Brown Shrikes of the Japanese form 'superciliosus'
  This form is now known to be regular through Korea.

• 6 Japanese Yellow Buntings
  Listed as a Species of Special Conservation Concern, the Yellow Bunting is still considered a major rarity by most Korean birdwatchers. However, as these records suggest, it is a regular and not too uncommon spring migrant, especially though the southwest, but even as far north as Eocheong island and at least as far east as Suncheon Bay.

Some of the above helped to start to re-write the status of a number of species in Korea, in some part due to a lack of previous observations of what are in the main birds of quite regular occurrence.

Daily Highlights

The following is a shortened list of daily highlights from 1993 and 1994.

1993

• 25th April 1993, Mosulpo (evening only)

  Red-necked Stint: 100, Long-toed Stint: 5, Sharp-tailed Sandpiper: 30, Black-winged Stilt: 1

• 26th April 1993, Mosulpo

  Streaked Shearwater: 2,000+, Marsh Sandpiper: 5, Red-necked Phalarope: 10,000+ , Yellow-browed Warbler: 30, Dusky Warbler:1, Taiga Flycatcher: 1

• 27th April 1993 Seongsan Po, SE Jeju (highlights only)

  Black-faced Spoonbill: 3, Black-winged Stilt: 2, Red-necked Phalarope: 5,000

• 28th April 1993, Mosulpo (evening only)

  Greater Sand Plover: 1, Grey-tailed Tattler: 11

• 29th April 1993, Mosulpo

  Pacific Golden Plover: 80, Redshank: 3, Little Whimbrel: 20 , Oriental Pratincole: 5 , Wryneck: 1, Needle-tailed Swift: 3, Asian House Martin: 14, Yellow Wagtail: 30, Pechora Pipit: 1, Red-throated Pipit: 3, Grey Thrush: 1, Dusky Warbler: 1, Narcissus Flycatcher: 1, Blue-and-White Flycatcher: 3

• 30th April 1993 Kapa Do and Mosulpo

  Chinese Pond Heron: 1, Chinese Egret: 2, Pintail Snipe: 1, Wryneck: 1, White Wagtail 'leucopsis': 10, Olive-backed Pipit: 30, Pechora Pipit: 1, Brown Shrike 'lucionensis": 5, Red-tailed Robin: 1, Grey-backed Thrush: 4 , Grey Thrush: 2, Brown Thrush: 2, Eyebrowed Thrush: 30, Yellow-rumped Flycatcher: 5, Blue-and-White Flycatcher: 4, Yellow-breasted Bunting: 10

• 1st May 1993, Mosulpo

  Greater Sand Plover: 2, White's Thrush: 3, Grey Thrush: 1, Brown Thrush: 2, Narcissus Flycatcher: 1, Mugimaki Flycatcher: 4, Japanese Paradise Flycatcher: 2

• 2nd May 1993 Kapa Do and Mosulpo

  Grey-headed Lapwing: 1, Swinhoe's/Japanese Snipe: 3, Needle-tailed Swift: 3, Pacific Swift: 70, Little Swift: 1 , Olive-backed Pipit: 70+, Siberian Rubythroat: 4, Eyebrowed Thrush: 20, Narcissus Flycatcher: 1, Mugimaki Flycatcher: 4, Yellow-breasted Bunting: 50+, Japanese Yellow Bunting: 6

• 3rd May 1993, Kapa Do and Mosulpo

  White-breasted Waterhen: 1, Greater Sand Plover: 1, Curlew Sandpiper: 3, Swinhoe's/Japanese Snipe: 1, Red-necked Phalarope: 1,000, Wryneck: 1, Siberian Rubythroat: 4, Red-flanked Bluetail: 1, Brown Thrush: 1, Dusky Thrush 'eunomus': 1 , Narcissus Flycatcher: 2, Yellow-browed Bunting: 10, Chestnut Bunting: 10, Japanese Yellow Bunting: 4

• 4th May 1993, Kapa Do and Mosulpo

  Red-necked Phalarope: 1,000, Grey Nightjar: 1, Greater Short-toed Lark: 1, Asian House Martin: 5, Pechora Pipit: 1, Bluethroat: 1, Brown Thrush: 2, Tristram's Bunting: 7

• 5th May 1993, Kapa Do and Mosulpo

  Chinese Egret: 1, Temminck's Stint: 1, Siberian Rubythroat: 6, Bluethroat: 1, Grey Thrush: 2, Brown Thrush: 12, Eastern Crowned Warbler: 14, Narcissus Flycatcher: 2, Red-cheeked Starling: 4

• 6th May 1993, Mosulpo

  Chinese Egret: 1, Whiskered Tern: 1 , Brown Hawk Owl: 1, Red-tailed Robin: 1, Siberian Blue Robin: 7, Siberian Thrush: 5, Narcissus Flycatcher: 2, Japanese Paradise Flycatcher: 2

• 7th May 1993, Mosulpo

  Temminck's Stint: 1, Oriental Pratincole: 2, Common Tern: 500, Whiskered Tern: 2, Grey Thrush: 1, Narcissus Flycatcher: 12, Red-cheeked Starling: 7

1994

• 1st May 1994, Mosulpo

  Siberian Thrush: 2, Brown Thrush: 5

• 2nd May 1994, Kapa Do and Mosulpo

  Red-necked Phalarope: 7,000, Asian Paradise Flycatcher: 1

  *The paradise flycatcher was seen very well in a small walled garden. My notes taken at the time read: -

  'Seen amazingly close. Presumably male because of length of tail streamers. Upperparts (mantle, scapulars, rump, wings and tail) the same uniform bright orange/chestnut. Tail streamers long (doubling the length of the tail). Head and upper breast black, sharply demarcated from white underparts. Bill and eye ring blue.'

• 3rd May 1994, Mosulpo

  Siberian Blue Robin: 15, Siberian Thrush: 5

• 4th May 1994, Mosulpo

  Oriental Pratincole: 2, Arctic Skua : 3, Pechora Pipit: 1

• 5th May 1994, Mosulpo

  Oriental Pratincole: 1, Dollarbird: 2, Pechora Pipit: 1

• 6th May 1994, Kapa Do and Mosulpo

  Chinese Pond Heron: 1, Pintail Snipe: 2, Red-necked Phalarope: 3,000, Black-capped Kingfisher: 7, Richard's Pipit: 4, Eyebrowed Thrush: 12, Radde's Warbler: 1, Taiga Flycatcher: 1, Japanese Paradise Flycatcher: 1

• 7th May 1994, Kapa Do and Mosulpo

  Chinese Pond Heron: 1, Red-necked Phalarope: 2,000, Oriental Pratincole: 6, Red-tailed Robin: 2, Siberian Rubythroat: 20, Japanese Paradise Flycatcher: 5

• 8th May 1994, Kapa Do and Mosulpo

  Chinese Pond Heron: 1, Black Kite: 1, Red-necked Phalarope: 2,000, Broad-billed Sandpiper: 1, Oriental Pratincole: 3, Red-flanked Bluetail: 1, Dusky Warbler: 1, Radde's Warbler: 1, Blue and White Flycatcher: 2, Japanese Paradise Flycatcher: 3, Yellow-browed Bunting: 1

• 9th May 1994, Kapa Do and Mosulpo

  Oriental Pratincole: 2, Greater Sand Plover: 1, Red-flanked Bluetail: 1, Brown Flycatcher: 10

• 10th May 1994, Mosulpo

  Oriental Honey Buzzard: 1, Greater Sand Plover: 1, Oriental Pratincole: 4, Dollarbird : 2, Siberian Rubythroat: 5, Siberian Blue Robin: 4, Radde's Warbler: 1, Eastern Crowned Warbler: 15, Japanese Paradise Flycatcher: 2

• 11th May 1994, Mosulpo

  Greater Sand Plover: 1, Curlew Sandpiper: 3 , Long-toed Stint: 1, Japanese Snipe: 1, Oriental Pratincole: 3, Red-flanked Bluetail: 1

• 12th May 1994, Kapa Do and Mosulpo

  Osprey: 1, Greater Sand Plover: 1, Broad-billed Sandpiper: 1, Oriental Pratincole: 3, Tiger Shrike: 1, Siberian Thrush: 1, Grey-streaked Flycatcher: 4, Japanese Paradise Flycatcher: 2, Grey-backed Starling: 1, Red-cheeked Starling: 1

• 13th May 1994, Kapa Do and Mosulpo

  Chinese Egret: 2, Oriental Pratincole: 2, Needle-tailed Swift: 2, Brown Hawk Owl: 1, Narcissus Flycatcher: 2, Grey-backed Starling: 1

• 15th May 1994, Mosulpo

  Chinese Egret: 3, Goshawk : 2, Curlew Sandpiper: 4, Oriental Pratincole: 2, White-winged Black Tern: 1, Needle-tailed Swift: 4, Little Cuckoo: 2, Tiger Shrike: 4, Siberian Blue Robin: 4, White-throated Rock Thrush: 1, Siberian Thrush: 2, Yellow-rumped Flycatcher: 4, Narcissus Flycatcher: 1, Japanese Paradise Flycatcher: 4

• 16th May 1994, Kapa Do and Mosulpo

  Chinese Egret: 3, Greater Sand Plover: 1, Red-necked Phalarope: 3,000, Swinhoe's/Japanese Snipe: 4, Oriental Pratincole: 9, Little Swift: 2 , Needle-tailed Swift: 1, Asian House Martin : 5, Eyebrowed Thrush: 10, Brown Thrush: 2, Siberian Rubythroat: 5, Narcissus Flycatcher: 1, Japanese Paradise Flycatcher: 1 , Chestnut Bunting: 15

• 17th May 1994, Kapa Do and Mosulpo

  Chinese Egret: 3, Swinhoe's/Japanese Snipe: 3, Red-necked Phalarope: 8,000 , Oriental Pratincole: 3, White-throated Rock Thrush: 1, Siberian Rubythroat: 5, Pallas's Grasshopper Warbler: 1, Radde's Warbler: 2, Dusky Warbler: 2, Yellow-browed Warbler: 8, Arctic Warbler: 11, Mugimaki Flycatcher: 4, Japanese Paradise Flycatcher: 3

• 18th May 1994, Mosulpo

  Chinese Egret: 2, Oriental Pratincole: 8 , Brown Hawk Owl: 1

• 19th May 1994, Kapa Do and Mosulpo

  Chinese Egret: 2, Schrenck's Little Bittern: 1, Red-necked Phalarope: 1,000, Oriental Pratincole: 2, Tiger Shrike: 4, Eyebrowed Thrush: 1, Siberian Rubythroat: 14, Red-tailed Robin: 5, Middendorff's Grasshopper Warbler: 19 , Pallas's Grasshopper Warbler: 1, Black-browed Reed Warbler: 21, Arctic Warbler: 11, Radde's Warbler: 2, Dusky Warbler: 2, Brown Flycatcher: 17, Japanese Paradise Flycatcher: 8, Chinese Grosbeak: 2

• 20th May 1994, Mosulpo

  Chinese Egret: 2, Tiger Shrike: 2, Siberian Thrush: 1, Dusky Warbler: 1, Arctic Warbler: 17, Siberian Flycatcher: 8 , Japanese Paradise Flycatcher: 1

Conclusions

The trips raised far more questions than they answered: -

• Is there significant migration throughout April?

• What happens even later in May?

• What happens in Autumn?

• The two years were rather different (e.g. far fewer thrushes and Narcissus Flycatchers in 1994. NB This was something also noted from Gageo and Heuksan Islands in 2000, 2001 and 2002, with 2000 producing many Blue-and-white Flycatchers, 2001 many Narcissus and Brown Thrushes, and 2002 perhaps rather fewer birds overall: NM). Which is more typical?

• What is the real status of some of the birds recorded?

• What other locations could offer comparable or better opportunities?

The answer to some of these questions are only now slowly starting to emerge.

What is certain is that these two trips provided some of the most exciting and enjoyable birding I have ever had, fuelled largely by the excitement of the unknown.

Other major positive factors were however the rapid turnover of birds (something new every day without fail), the good views of super birds in good plumages, the happy geography and topography of the area which made finding migrants easy, the easy accommodation/transport and the complete lack of hassle.

References:

• Brazil M., 1991. The Birds of Japan . Helm. Won P-O and M.E.J. Gore. 1971.The Birds of Korea. Royal Asiatic Society, Korea Branch, Seoul.