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Friday, January 3, 2014

Spoon-billed Sandpiper in Mekong delta

Spoon-billed Sandpiper survey in Mekong Delta 2013
Nguyen Hoai Bao 1 , Nguyen Hao Quang 2 , Tran Duc Thien 1
1 University of Science, Vietnam National University in Ho Chi Minh city
2Wildtour Co., LTD

Acknowledgement
We would like to take this opportunity to thank to RSPB who has sponsored our travelling expense for this survey. Especially thank to Hoang Thanh Ha from Viet Nature, she has worked very hard to make connections among us. We also would like to thank to Wildtour Co., LTD has supported their staff to arrange logistics and carry out survey.
video

1. Introduction

Spoon-billed Sandpiper (Eurynorhynchus pygmeus) is a critically endangered species (IUCN redlist 2013). It’s breeding in Russia and wintering down the western Pacific coast through Russia, Japan, North Korea, South Korea, mainland China, Hong Kong (China), Taiwan (China) and South-east Asia including Myanmar, Thailand and Vietnam.

Mekong Delta is one of key remaining SbS wintering sites. The survey done by Birds Russia collaborated with University of Science in Ho Chi Minh city in 2011 had recorded up to 8 or at least 5 birds (Vladimir et al., 2012). In additional, by personal observations, there was 1 record in Can Gio area in end of April, 2010 (Nguyen Hoai Bao) and 1 record also in Can Gio in October 2010 (Jonathan Eames, personal communication). An older survey in 2000 by Moores, N. and Nguyen Phuc Bao Hoa has reorded up to 5 individuals in Ba Tri area.

This one-week survey therefore could be a desirable data to support mornitoring SbS as well as waders population wintering in Mekong delta, especially at the IBAs along coastal in the southern Vietnam.

2. Sites selection

Following survey in 2012, we chose potential sites for SbS at districts Can Gio (Ho Chi Minh city), Go Cong (Tien Giang province), Binh Dai, Ba Tri and Thanh Phu (Ben Tre province), see figure 1.
Figure 1. Surveyed sites

3. Survey itinerary

December 16, 2013. Traveling to Can Gio, survey at Can Thanh area, roost sites. Travel to Go Cong in the afternoon.
December 17, 2013. Survey at Tan Thanh beach, clam farms
December 18, 2013. Survey at Con Ngang (Ngang island). Travel to Binh Dai.
December 19. Survey at Binh Dai, travel to Ba Tri
Dec 20. Survey at Ba Tri, travel to Thanh Phu
December 21. Survey at Thanh Phu
December 22, 2013. Travel to Sai Gon, finishing survey.

4. Findings (Outputs)
During survey, at least 3 Spoon-billed Sandpipers were recorded, up to five birds were observed. We also counted or estimated other waders occurs at surveing sites (table 1).

Can Gio (December 16, 12:30-16:30)
GPS information: site 1 -  10.399388°/106.944365°; site 2 -  10.399776°/106.925338°; site 3 -  10.394532°/106.927869°.

Can Gio is one of the most important sites for shorebirds during wintering time. There are thousands birds using both muddy beach as feeding habitats and mangroves as roosting spot. The salt-pans along the coastal areas are also feeding habitats for them during high tide. The survey in 2011 indicated that the beach is to sandflat which too hard for SbS, the two observations were at roost sites.  
Therefore we only observed at roost sites (figure 2), the most abundance including Great Knot, Lesser Sand Plover, Pacific Golden Plover, Bar-tailed Godwit.

Figure 2. Waders roosting spots in Can Thanh, Can Gio
Tan Thanh, Go Cong (December 17, 08:20 – 11:30)

Figure 3. One of SbSs sighting on December 17 at Tan Thanh
GPS information: 10.274425°/106.778375°

This site is situated at the outer of Mekong river (Song Tien), the most important for Spoon-billed Sandpiper in Mekong delta, Vietnam. Recently sightings proved that SbS using muddy beach, clam farms for feeding during winter. It occurs here beginning in mid November to mid April (Wildtour’s team observed 2011-2013).
Beside three to five individuals of SbS were sighted, we also found that so many Red-necked Stints, Broad-billed Sandpipers and other wadres feeding at this site.


Con Ngang, Go Cong (December 18, 06:00-11:30)
GPS information: 10.224844°/106.792337°


Although three SbSs were seen at this site in 2011, we did not any at this time. The habitat at 2011-sighting spot seem to be changed after two years, soil is less mud and harder than before. However, this island is very important roosting site for those birds in Tan Thanh and Binh Dai. When tide was coming up, we saw thousands waders flew in which were estimated 700 Pacific Golden Plovers, 1000 Great Knots, 200-250 Bar-tailed Godwits, 100 Far Eastern Curlews, 300 Caspian Terns.

Figure 5. A flock of Great Knot flying to Con Ngang during high tide

Thoi Thuan, Binh Dai (December 19, 08:00-10:00)
GPS information: 10.040256°/106.711518°

We couldn’t access clam farms in Thoi Thuan as it belongs to a private company and it is also a restrict frontier area, the local authorities required us special permit to enter their area. Therefore, we were only able to survey at some salt-pans and swimp ponds nearby, not many species were observed, Marsh Sandpiper (100+), Common Greenshank (29), Common Redshank (11), Golden Plover (24), Caspian Tern (2). None wader-birds including Little Egret (32), Yellow-vented Bulbul, Olive-backed Sunbird, Plain Prinia, Collared Kingfisher.

An Thuy, Ba Tri (December 20, 09:30-13:30)
GPS information:  9.980347°/ 106.658725°


Figure 6. Black-tailed Godwit
This is an IBA (code VN 063) classified by Birdlife International. The beach is using as clam farms, ground is sandy and quite hard for SbS, we thought. This is considered as impact from less sediment due to hydropower dams along Mekong river and especially Ba Lai drain and dykes were built along coastal in this area (?). We spent 4 hours checking around, birds encountered were Golden Plover (150), Far Eastern Curlew (30), Common Greenshank (45), Bar-tailed Godwit (60), Red-necked Stint (230), Sanderling (56), Terek Sandpiper (37), Lesser Sand Plover (250), Kentish Plover (70). 
In the end, we birded at the mangroves and found our first near-threatned Black-tailed Godwit (1), Little Egret (7), Great Egret (12), Intermediate Egret (6), Great Heron (1), Little Heron (1), Common sandpiper (2), Blue-tailed Bee-eater (3), Common Myna (2), Pied Fantail (5), Golden-bellied Gerygone (4).

Thanh Hai, Thanh Phu (December 21, 09:00-13:00)
GPS information:  9.865881°/ 106.686575°

Our final survey was at Thanh Phu district, this is new site as we did not survey in 2011. By looking on google maps, we found a good mudflat by outer of Ham Luong river. However, there were no SbS there nor many shorebirds observed. Thanh Phu was a proposed for a natural reserve area but wasn’t designated, all mangroves surround was cut down for shrimp and crab farms.

5. Threats

We saw no direct threat to Spoon-billed Sandpiper as well as other shorebirds, there was no hunting or trapping. However, habitats lost probably the main issue. The roosting sites along coastal areas in Ben Tre province have changed to aquaculture might impact waders population. The less sediment also be considered as theat to SbS feeding habitats.

6. Recommendations

1) Again, as we recommended after survey in 2011, International and local organizations on birds protection should address to responsible governmental agencies in Vietnam with request on creation protected territories at wintering grounds and staging areas of Spoon-billed Sandpiper and huge concentration of waterbirds (mudflats at Tan Thanh village, Ngang Island). By the first step to this direction could be declaration these territories as IBA. A reserve area should be assigned to protect and sustainable using SbS feeding habitats.

2) Yearly monitoring or survey to understand waders population at these areas

3) Conduct survey in the areas further south such as Tra Vinh, Soc Trang and Bac Lieu province which are not been done before.

Follow update more sightings



Table 1. List of the birds recorded on SbS survey
(names follow Clements checklist version 6.7)

SCIENTIFIC NAME
ENGLISH NAME
Thanh Phu
Ba Tri
Binh Dai
Con Ngang
Tan Thanh
Can Gio
Anatidae (Ducks, Geese, and Waterfowl)






Anas poecilorhyncha
Indian Spot-billed Duck
2





Podicipedidae (Grebes)






Tachybaptus ruficollis
Little Grebe
1





Phalacrocoracidae (Cormorants and Shags)






Phalacrocorax niger
Little Cormorant
3




1
Ardeidae (Herons, Egrets, and Bitterns)






Ixobrychus sinensis
Yellow Bittern
1




1
Ardea cinerea
Gray Heron

1

1


Ardea purpurea
Purple Heron
1





Ardea alba modesta
Great Egret (Australasian)

12

1


Mesophoyx intermedia
Intermediate Egret

6




Egretta garzetta
Little Egret
20
7
32
30
25
7
Butorides striata
Striated Heron

1



1
Rallidae (Rails, Gallinules, and Coots)






Gallinula chloropus
Eurasian Moorhen
1





Charadriidae (Plovers and Lapwings)






Pluvialis squatarola
Black-bellied Plover





200
Pluvialis fulva
Pacific Golden-Plover

150
24
700

80
Charadrius mongolus
Lesser Sand-Plover
60
250

80
1000
400
Charadrius leschenaultii
Greater Sand-Plover




200
15
Charadrius alexandrinus
Kentish Plover

70

20
300
27
Charadrius dubius
Little Ringed Plover





9
Recurvirostridae (Stilts and Avocets)






Himantopus himantopus
Black-winged Stilt





26
Scolopacidae (Sandpipers and Allies)






Xenus cinereus
Terek Sandpiper

37

4
150
16
Actitis hypoleucos
Common Sandpiper
3

2

3
6
Tringa nebularia
Common Greenshank
5
45
29
7
60
6
Tringa guttifer
Nordmann's Greenshank




2

Tringa stagnatilis
Marsh Sandpiper


100

40
26
Tringa totanus
Common Redshank


11



Numenius phaeopus
Whimbrel
16


24
20
10
Numenius madagascariensis
Far Eastern Curlew
40
30

97
30

Limosa limosa
Black-tailed Godwit

1




Limosa lapponica
Bar-tailed Godwit
32
60

250
3
98
Arenaria interpres
Ruddy Turnstone




5
22
Calidris tenuirostris
Great Knot



1000

330
Calidris alba
Sanderling

56

6


Calidris ruficollis
Red-necked Stint

230

60
100
20
Calidris minuta
Little Stint



20


Calidris subminuta
Long-toed Stint




200
71
Calidris ferruginea
Curlew Sandpiper



8
7
3
Limicola falcinellus
Broad-billed Sandpiper



14
10
23
Laridae (Gulls, Terns, and Skimmers)






Chroicocephalus ridibundus
Black-headed Gull



20


Gelochelidon nilotica
Gull-billed Tern



6
45

Hydroprogne caspia
Caspian Tern
80

2
300


Columbidae (Pigeons and Doves)






Streptopelia tranquebarica
Red Collared-Dove
3




4
Cuculidae (Cuckoos)






Cacomantis merulinus
Plaintive Cuckoo
2





Alcedinidae (Kingfishers)






Alcedo atthis
Common Kingfisher





2
Halcyon smyrnensis
White-throated Kingfisher





1
Todiramphus chloris
Collared Kingfisher
10




5
Meropidae (Bee-eaters)






Merops philippinus
Blue-tailed Bee-eater

3




Acanthizidae (Thornbills and Allies)






Gerygone sulphurea
Golden-bellied Gerygone

4




Laniidae (Shrikes)






Lanius cristatus
Brown Shrike
2





Rhipiduridae (Fantails)






Rhipidura javanica
Pied Fantail
13
5



6
Alaudidae (Larks)






Alauda gulgula
Oriental Skylark





20
Hirundinidae (Swallows)






Hirundo rustica
Barn Swallow
150





Pycnonotus goiavier
Yellow-vented Bulbul
3
2




Sturnidae (Starlings)






Acridotheres tristis
Common Myna

2