This is a summary of count data (and habitat assessment) from the second of the four spring-tide cycles of the 2008 Saemangeum Shorebird Monitoring Program (SSMP), a joint initiative of the domestic organization Birds Korea and the international Australasian Wader Studies Group. This program was launched in 2006 to monitor the impacts of the 40,100 ha Saemangeum reclamation (i.e. wetland destruction) project on globally important populations of shorebirds supported by this estuarine system, already recognized as the most important known shorebird site in the Yellow Sea (Barter, 2002). These data and information will be refined further, for publication in the SSMP 2008 Report and in other papers, and can be cited freely by others (with proper acknowledgement and caveats).
Following several days of neap-tide counts, a total of 13 people participated in dawn to dusk land- and boat-based survey work for the SSMP Second Count Cycle between April 18th and 20th, covering the Geum Estuary, the Saemangeum area, and Gomso Bay. These counters and reporters were also joined at times by a further three local members of the Geum River Korea Wetlands project office, by one Birds Korea photographer, and by two staff of the Hangyoreh Newspaper. Repeat counts planned between April 23rd and 26th were cancelled due to poor weather.
During the Second Cycle count period, day-time spring tides peaked at only 604 cm (compared to 674 cm in 2007), leaving a wide expanse of uncovered tidal-flat at the Geum Estuary, and requiring counting by four teams (one at Yubu Island, one at Daechuk Island, and two on the mainland). Within the Saemangeum reclamation area tidal-range by contrast appeared to increase from c. 20 cm a day to probably c. 50 cm during the count period, before overall water levels were then dropped by c. 1m, followed by several days of tidal-range of less than 10 cm. While the reasons remain unclear, there has been another massive die-off in benthos in many parts of the system coinciding with these changes in water levels, leaving masses of recently-dead shellfish on the tidal-flat surface at for example both Simpo and near the airport.
In total, despite the difficult conditions (especially for the birds but also for the counters), 107,623 shorebirds were counted during this count period, with 58,574 in the Geum Estuary, 46,018 within the Saemangeum reclamation area (the vast majority in the outer parts of the system), and 3,031 at Gomso Bay. These compare to SSMP counts during the Second Count Cycle period (April 15th-19th, 2007) of 50,560 shorebirds at the Geum Estuary, 69,411 shorebirds within Saemangeum, and 2,941 at Gomso Bay.
Within the SSMP count area, Dunlin Calidris alpina (51,478), Great Knot Calidris tenuirostris (26,429) and Bar-tailed Godwit Limosa lapponica (16,416) were the most numerous shorebird species, followed by Grey Plover Pluvialis squatarola (6,057) and Far Eastern Curlew Numenius madagascariensis (2,114).
At the Geum Estuary, eight shorebird species were recorded in Ramsar Convention-defined internationally important concentrations (i.e. 1% or more of population), based on Wetlands International (2006): Eastern Oystercatcher Haemaptopus (ostralegus) osculans (4%), Grey Plover (3%), Bar-tailed Godwit (4% of combined totals of baueri and menzbieri subspecies), Eurasian Curlew Numenius arquata orientalis (2%), Far Eastern Curlew (7%), Nordmann’s Greenshank Tringa guttifer (with 11 or 12, or 1.5% of the total world population counted in one scan at the Geum Estuary on April 16th), Great Knot (3%) and Dunlin (1% of combined total of sakhalina and articola). In addition, 6 Black-faced Spoonbill Platelea minor (Endangered), one Chinese Egret Egretta eulophotes (Vulnerable) and 6 Saunders’s Gull Larus saundersi (Vulnerable) were also logged during the count period.
Within the Saemangeum reclamation area, five shorebird species were again also found in Ramsar Convention-defined internationally important concentrations (as described above): osculans Eastern Oystercatcher (1%), Grey Plover (1-2%), Bar-tailed Godwit (1% of combined totals of baueri and menzbieri subspecies), Great Knot (3%) and Dunlin (1% of combined total of sakhalina and articola). In addition, one Black-faced Spoonbill and five Saunders’s Gull were recorded during the count period. Clearly, while much degraded (and already supporting significantly reduced numbers of shorebirds), the Saemangeum reclamation area remains an internationally important wetland for waterbirds. Restoration of an increased and regular tidal-flow would greatly reduce the impacts on shorebirds caused by this massive loss and degradation of habitat.
At Gomso Bay, no shorebird species were recorded in internationally important concentrations, though the site supported 11 Endangered Black-faced Spoonbill.
Counting in preparation for the Third count cycle (planned for May 4th-9th) started again on April 27th, resulting in three Critically Endangered Spoon-billed Sandpiper Eurynorhynchus pygmeus being found on April 28th within the Saemangeum reclamation area, near to Gunsan airport.
Our thanks to all who continue to support this extremely important project.
SSMP Team, Iksan, April 29th, 2008.
References
- Barter, M.A. 2002. Shorebirds and The Yellow Sea: Importance, threats and conservation status. Wetlands International Global Series 9, International Wader Studies 12, Canberra, Australia.
- Wetlands International. 2006. Waterbird Population Estimates – Fourth Edition. Wetlands International, Wangeningen, The Netherlands