Convention on Wetlands

Home , Asian dowitcher, Asian openbill, Giant ibis, Manchurian reed warbler

The Regional Training Course on SUSTAINABLE USE AND MANAGEMENT OF COASTAL WETLANDS 5 – 20 November 2007 Faculty of Environment and Resource Studies, Mahidol University, Thailand

TOPIC 7 Birds of Wetlands Friday, 9 November 2007 : 08.30 – 12.00 hrs.

Philip Round Department of Biology, Faculty of Science Mahidol University Rama 6 Road, Bangkok 10400, Thailand [email protected] Wetlands and Waterbirds

Birds are important bio-indicators –Conspicuous – Easily identified and counted – Present in virtually all environments/habitats

Ramsar Convention : Convention on Wetlands

Full title?

Convention on Wetlands of International Importance especially as Waterfowl Habitat What are wetlands?

• Permanently or seasonally inundated land • Both fresh-water and brackish/marine • Including man- modified wet habitats, e.g. rice paddies, fish-ponds, etc. Intertidal/marine Inshore coastal waters and associated rocky islets Sand beaches Mangroves Mudflats/estuaries Brackish-water coastal flats Prawn ponds and fishponds Salt-pans

Working classification of wetlands for use in SE Asia Freshwater Rivers Lakes Ponds Canals Marshes Grazing land Paddies Swamp-forests Reservoirs see Scott and Jones (1995) or http://www.ramsar.org/key_guide_inventory_e.htm (Ramsar Convention) dependent on wetlands” “a species of bird that is ecologically

What is a waterbird? •Combines elements of both ecology and taxonomy •Definition is broad and not altogether clear What is a waterbird? But what about this warbler?

Ferruginous Pochard Manchurian Reed Warbler This duck certainly is!

Or this All these species are eagle? ecologically dependent on wetlands and may be considered as waterbirds or as “wetland-associated” Greater Spotted Eagle .

etc Shorebirds (waders) Herons, egrets, storks, cranes, ibises (e.g, (ducks, geese and swans) (ducks, geese Wildfowl birds Wading (waders) Miscellaneous cormorants, grebes, pelicans, rails, etc.) .,kingfishers, some

e.g Wetland- associated ( warblers, wagtails, chats, raptors, etc.) Waterfowl A classification of terms used with waterbirds 280 are wetland species / 970 bird species in Thailand wetland-associated Waterbirds Both sometimes called ‘waders’ or ‘wading birds’!

Long-distance migrants

Order Charadriiformes- Herons and egrets- shorebirds- eat small benthic invertebrates “large wading birds” – on intertidal mudflats eat mainly fish Very different ecological requirements! Mainly resident/dispersive Migration:

Roughly 60% of SE Asian wetland birds are migratory or dispersive

Migration- regular, repeated seasonal movements to different geographical areas at different times of year Migration Most migrants are Palearctic-Tropical migrants Most of the birds wintering in SE Asia breed E of about 90°E longitude Very different ecological conditions on breeding areas vs., wintering areas

Great Knot Great Knot- world population 380,000

BREEDING AREA

NON-BREEDING AREA via a chain wintering areas with breeding areas

Flyway: staging areas Convenient to subdivide even non-migratory species into flyway populations of -a route traveled by a group of populations migratory waterfowl -links -Orientation mainly N- S areas are as important breeding in annual cycle in enabling birds to feed en route- lay 2-3 months on breeding areas 6-7 months in their wintering very important very important down fat reserves to sustain their migration Staging areas- Wintering areas - areas Migrant waterbirds: Wintering areas and staging Migrants may spend only But - Use of migratory staging posts “refuelling stops”

Staging areas

Asian Dowitcher Limnodromus semipalmatus

Main wintering area East Asian-Australasian Flyway • Some overlap with Central Asian flyway – • Could be subdivided further (SE Asian and extreme E Asian-Australasian) EastAsian- Australasian flyway Ramsar Criteria

A wetland is considered of international importance if it:

•supports an assemblage of rare, vulnerable or endangered species

•regularly supports >20,000 waterfowl

•supports >1% of the flyway population of a species

Population estimates upated every three years Asian Waterbird Census

Coordinated count carried out continent-wide in mid January >5,700 sites since commencement in 1987 1997-2001 > 1,000 participants in 22 countries; 1352 sites covered

Types of wetland habitats and their birds Primary peat swamp forest

Tall, multi-storied; species- rich

Phru To Daeng > 400 spp. of flowering plants Phru To Daeng, Narathiwat Province, Thailand

Pre-1980: area c. 340 km2 of primary peat swamp forest

1987: only 96 km2 of primary peat swamp forest remained

1998 onwards: how much remains?

Ramsar site since 2001 Peat swamps support a diverse forest bird fauna Most bird species shared with lowland mixed dipterocarp forest

Many are threatened/endangered

Phru To Daeng 217 bird species

Red-naped Trogon

Cinnamon-headed Pigeon

Malaysian Blue Flycatcher Peninsular Malaysian Peat Swamp Forests

Total area 3,600 km 2

Percentage protected ? = Zero

Wikramanayake et al. (2002), Terrestrial Ecoregions of the Indo-Pacific. Island Press, Washington, D.C. of Melaleuca 2 woodland A fire-climax following repeated burning of peatswamp forest e.g., at Thale Noi Ramsar c. 42 km site, woodland Melaleuca Low plant diversity Bird diversity low/ most species shared with e.g., mangroves/non-forest habitats

e.g., colonies of nesting and roosting colonial waterbirds Ultimately degraded peatswamp

Low productivity rice paddy

Acid sulphate soil conditions (pH 4- 5)

Birds present are typicaly those that are common and widespread in a range of wetland and non-wetland habitats Lakes

Open water

Floating vegetation

Emergent/fringing vegetation Wildfowl (ducks): Anatidae:

Mobile and adaptable

Key requirements: undisturbed water bodies on which to roost feeding areas (usually croplands such as rice paddy) Garganey

The most numerous SE Asian wintering Palearctic dusk SE Asia - The commonest duck is usually the Lesser Whistling Duck – NOT a long-distance migrant but a resident or locally dispersive bird.

Associates in flocks when not breeding Floating vegetation

Provides shelter and support for feeding and nesting of (chiefly) resident species

e.g., Pheasant-tailed Jacana Lake margins, swamps and ecotones: emergent vegetation Purple Heron Emergent lakeshore vegetation provides habitat for herons and bitterns Yellow Bittern Streaked Weaver at nest

Asian Golden Weaver

Roosting, feeding and nesting areas for weavers (Ploceidae)

Typha Eleocharis Phragmites Reedbeds Sarus Crane- requires extensive areas of seasonally flooded grassland reeds around lake margins and in swamps

Phragmites are a very important habitat for great range of waterbirds, large and small Lake margins, swamps and ecotones: emergent vegetation An ornithologist takes a reed warbler a mist-net from for banding An ornithologist Reed Warblers, Acrocephalus spp. Black-browed Reed Warbler Manchurian Reed Warbler

Acrocephalus bistrigiceps Acrocephalus tangorum Manchurian Reed Warbler Acrocephalus tangorum globally threatened Maybe in Myanmar? Where does it breed? Where does it winter? UNTIL one was netted during routine ringing operations at March 2006 in a sewage farm, Phetchaburi, Thailand Only known from one specimen collected in NW India 1867 Large-billed Reed Warbler: Acrocephalus orinus 0.016 1 0.009 9 0.005 45

orientalis 0.025 3 0.03 6 0.003 6 0.002 13 0.005 68 Total metre-hours of net = 14498 Total metre-hours 0.01 2 0.00031 19 0.0004 0.0030 35 0.005 0 15 0.022 tangorum concinens bistrigiceps n n/mh n n/mh n n/mh n n/mh mh 2706 60 netted 7274 0 0 1829 0 2579 2 0.0008 (6 , young Typha , young Phragmites (one site) 110 1 0.009 (one site) s) 4 sites

Distribution by habitat of 4 species Acrocephalus warblers at Khao Sam Roi Yot during April 1995 Typha Scirpus sites) Pure, mature Habitat Marginal (open Phragmite Pure Pure sites) (two Scrub Reedbeds are threatened by drainage and clearance:- aquaculture

agriculture GLOBALLY THREATENED! HAS ALMOST VANISHED!

Winters only in Philippines On migration in E and NE China

A. sorghophilus Breeds where? Streaked Reed Warbler Mudflats

e.g. Inner Gulf of Thailand tidal flats 235km2 OFFSHORE HABITAT shrimp ponds 400 km2 ONSHORE HABITATS salt-pans 106 km2 Shorebirds - long, sensitive, flexible bills for probing in soft sediments. A range of bill shapes and sizes enables different shorebird species to divide up the resource base

Usually gregarious away from breeding areas, often occurring in huge flocks, as in these Black-tailed Godwits World: ca. 215 species. SE Asia: ca. 72 species Thailand: 64 species Shorebirds fly to roost on drained prawn-ponds and salt pans Some of the most numerous shorebirds wintering in the gulf

Red-necked Stint

Marsh Sandpiper

Black-tailed Godwit

Lesser Sand Plover

Common Redshank Curlew Sandpiper 19 HOW MANY? Spoon-billed Sandpiper Eurynorhynchus pygmaeus Status: endangered, declining World population: > 1000 individuals

Winter visitor in small numbers to tidal flats, salt-pans in S and SE Asia. Largest concentrations on passage around the Yellow Sea (single counts of 100-180 birds) Declined by 60-80% in two decades A variety of human uses continues alongside use of the area by waterfowl Mudflat “reclamation” Yellow Sea- Korea & China Spoon-billed Sandpiper •Used by ca. 2,000,000-3,000,000 –perhaps 50% of the migratory shorebirds per year world populatiom)

•36 shorebird sp. in internationally important concentrations

•tidal flats ca. 20,000 km2 - 40% already reclaimed

•Plans in hand to reclaim a further 43%

Great Knot Calidris tenuirostris 300,000- 400,000 – 90% of the world population One reclamation alone at Saemangeum, Korea is in the process of destroying 400 km2 of coastal; flats Large areas of shoreline are:- Industrialization Urban sprawl Pollution little remaining space for shorebirds

Mudflat reclamation the next step?

Shorebirds

•511 discrete populations worldwide

•96 (19%) declining

•72 stable

•32 increasing

•304 (59%)– no information Conservation issues Wetlands are probably the least well conserved habitat of all tropical habitats

-human use for x 000s of years

•hunting/fishing

•agriculture

•transport & communications

•Other? Wildfowl: including ducks, Anatidae:

Mobile and adaptable

Key requirements: undisturbed water bodies on which to roost feeding areas (usually croplands such as rice paddy)

Lesser Adjutant

Giant Ibis

Sarus Crane

Unmodified floodplain – open forest and small ponds / waterholes – once supported a megafauna of large birds and mammals. Now largely cleared and replaced by rice-paddies Almost entirely lost!

Kulen Promthep Wildlife sanctuary one of the last extensive areas supporting an intact lowlandfauna The lowland bird megafauna

Giant Ibis White-shouldered Ibis Most of these species are Sarus Crane endangered/critically endangered in SE Woolly-necked Stork Asia Black-necked Stork Lesser Adjutant Greater Adjutant Bengal Florican

All species associated with grasslands/ponds /open forests of little- disturbed lowland floodplains Some larger waterbirds: vulnerable or near- threatened- may be increasing again

Painted Stork

Spot-billed Pelican

Why?

Oriental Darter Species that are threatened/near-threatened but which may be again increasing

Better protection at breeding Painted Stork colonies in Cambodia Spot-billed Pelican Can use artificial wetland habitats, e.g., Oriental Darter fish-ponds, irrigated areas

Fish-eating- benefit from increased aquaculture

In some cases numbers may be augmented by released captives Paddies: traditional paddies – one crop per year, long fallow period and low pesticide input.

Still support a rich array of birds Agricultural intensification Two or three crops of irrigated high-yield rice: use of herbicides, pesticides and rodenticides

Area of irrigated rice increased from < 1600 km2 in 1974 to 6400 km2 by 1996 (Source: Molle et al., 2001)

•Habitat mosaic- always some wet areas May benefit some waterbirds such as egrets and Asian Openbill Anastomus oscitans

•Loss of the fallow period

•loss in overall biodiversity driven by reduction in populations of insects and weeds Changes in abundance of farmland birds around the Lower Central 120 Plain

100 Shrikes 80

schach 60 cristatus

6 7 2 4 5 6 1 1 Insectivorous species have 8 8 88 89 9 92 93 93 9 9 9 97 98 0 0 02 9 9 9 9 9 9 1984 1985 19 19 1 1 1990 1991 19 19 1 1 1994 19 19 19 1 1 1999 2000 20 20 20 shown a marked decline 600

500 Egrets

400

Egretta 300 Bubulcus

200

100

0 Egret numbers have remained

5 0 3 4 8 1 2 more or less stable 87 91 92 95 99 00 98 986 9 988 99 9 992 9 99 99 994 9 996 99 9 0 00 00 1984 1 1 1 1 1989 1 1991 1 1 1 1 1993 1 1 1 1 1997 1 1 2 2001 2 2 Cascade of extinctions/effects

1) Ibises, White-winged Duck, Sarus Crane; mammal megafauna Cause: low-intensity use, hunting, etc.

2) Storks, Adjutants, Pelicans Cause: large-scale habitat conversion

3) Collapse of insectivorous bird community Cause: adoption of high-yield rice cultivation, irrigation, pesticides, etc. Rivers present special problems

•Linear habitats •Resources shared by many users (e.g., Mekong River, 6 countries) •Used for transport and communications •fisheries, irrigation, etc. and very heavily impacted

Peoples’ Republic of China is currently engaged in blasting rapids and dredging sandbanks to allow the passage of large boats (500 tonnes) along the Mekong between S. China, N. Thailand and Laos. This will destroy habitat for sand-bar nesting birds such as River Tern Sterna aurantia and Great Thick-knee Esacus recurvirostris (above). Blasting of rapids and dam construction on the Mekong River -intertidal mudflats offshore - zone of low extensive intensity prawn ponds/salt pans onshore

Coastal areas Conventionally, most emphasis placed on mangroves BUT very few waterbirds are limited to this habitat Key habitats for shorebirds: Planting mangroves on mudflats alters the habitat: -prevents access for feeding by shorebirds

- Impact on mudflat benthos not fully understood. ca. 130 km2 of mangroves planted on intertidal areas in 18 Thai provinces during the last 6 years sed c. 0.6 C in last 100 years Rising sea-levels Inundation of mudflats Reclamation- construction of sea barriers - more fires Thawing of permafrost causing drying out tundra wetlands Particularly threatening for high arctic nesting waterbirds Global temperatures have increa Breeding areas Wintering areas

Climate change Disappearing duck!

•Formerly 100+ at several sites in Thailand (largest count 596) •No more than 10 have been seen anywhere in recent years Baer’s Pochard Aythya baeri

•Yangtse Valley >500,000 waterbirds counted 2005 - only 8 Baer’s Pochards East Asian Australasian flyway •Human pressure greater than in any other •80% of all wetlands are classified as threatened •Very high percentage of the world’s threatened waterbirds •(e.g. holds 58% of all the world’s threatened species of shorebirds)

Many of the most immediate threats come from governments • Korea and China “reclaiming” mudflats of the Yellow Sea • Thailand at least 7 out of 10 Ramsar sites are threatened by government schemes

Government support for monitoring Integrate findings in better land-use planning Asia Pacific Migratory Waterbird Strategy adopted at the Ramsar Convention in 1996. Action plans for Anatidae, Cranes, Shorebirds developed • Key elements include: – Information exchange – Training – Education and awareness – Migratory bird research – Development of site networks

• East Asian-Australasian Shorebird site network : 31 sites in nine countries Techniques How to estimate numbers of waterbirds?

Wetland habitats are discontinuous direct counts appropriate, especially when birds are concentrated

•At roosts •breeding colonies •feeding areas

Transects across feeding areas yield information on habitat use

Coordinated counts by teams of observers in larger wetlands Black-faced Spoonbill Platalea minor

2005 Census 1,475 birds Sometimes estimates may be wrong by even an order of magnitude

Oriental Pratincole Glareola maldivarum

Wetlands International (2003) estimate was 75,000

BUT 2.88 million were counted in NW Australia in February 2004 (Sitters et al., 2004) Turnover-complicates assessment of the numbers of birds using a site

“Rule of thumb” for migratory shorebirds, estimated migratory population at a site is roughly 4 x the maximum count Usage (bird-days): average of a series of counts x time interval (days) may provide a more meaningful estimate of total usage than just numbers Different populations or subspecies may use different wintering sites/staging areas

How do we identify them?

Red Knot Calidris canutus Capture and marking

Mist-nets erected for catching waterbirds Methods of marking Ringing or banding: used for over 100 years

Numbered metal band applied to the leg of a bird Recoveries of ringed birds build up a picture of origins and destinations.

Ruddy Turnstones wintering in UK come from two discrete breeding areas, from Greenland and Scandinavia Colour-marking methods

Enables place of origin of marked individuals to be identified non-intrusively.

One colour combination per flyway site

Ringed in S. Australia A leg-flagged Curlew Sandpiper Resighted Inner Gulf of Thailand, April 2005

7062 km, with a bearing of 316 degrees, from the marking location Leg-flagging

>250,000 shorebirds ringed in Australia 126,000 leg-flagged (since 1990)

•534 recoveries •3903 sightings LEG FLAG CODES FEBRUARY 2007

RUSSIA CHINA Pale Blue Pale Blue Pale Green Yellow Yellow Green White Black White nothing nothing Black White Orange Black White

Wrangel Isl. NChukotka S Chukotka Kamchatka Sakhalin N Yellow Sea Chongming Dao Chongming Dao

Taiwan Hong Kong Korea Blue Blue Blue Blue (angled) Blue White White White Blue nothing White White (angled) Orange Blue Yellow Orange Hokkaido C Japan S Japan L. Komuke Shunkunitai Obitsu Yatsu Tidal Flats Kyushu

SINGAPORE PHILIPPINES THAILAND INDONESIA AUSTRALIA Green Black Black Black Yellow Yellow Green Orange White Blue Green Orange Orange nothing nothing Green

Singapore N Philippines Inner Gulf Java SW WA NWA QLD NSW

AUSTRALIA NEW ZEALAND USA Orange Orange Orange Orange Orange White White Yellow band nothing Blue Yellow Blue Yellow nothing Green Green flag Victoria Tasmania SA Tasmania SA North Island South Island Alaska

Radio-telemetry

Often used to study movements of e.g territorial birds that only move short distances Advantage: transmitters are small and light-weight (down to 0.4 g)

Disadvantages: - can only be used where the bird can be tracked at short range. – of limited use for highly migratory species Radio telemetry- may be used for species that do not disperse long distances

e.g, tracking feral /released Painted Storks Satellite telemetry

Advantage: •Can follow birds for long (globe-spanning) distances

Disadvantage: •very expensive •Transmitters are rather large (4-15 g) and can only be fitted to larger birds Satellite tracking of Lesser Whitefronted Goose Anser Satellite-tracking of the Black-faced Spoonbill Platalea minor Counting methods Direct counts or direct estimates

Make life easy for yourself!

Use a tally counter for large numbers

Block off in groups of ten, or twenty, or fifty, depending on the size of the flock

(After Howes and Bakewell, 1989) How many birds?

This flock contains 9 blocks of an estimated 50 birds per block = 450 birds.

Actual flock size = 491 birds

After Howes and Bakewell (1989)

With practice, counts will usually be accurate within 10% HOW MANY?

n= 21 13 HOW MANY?

n = 36 14 HOW MANY? n = 210 15 HOW MANY?

n= 4000 17 HOW MANY? n = 140 18 HOW MANY?

n = 550 19 HOW MANY?

n = 20,000 Many large waterbirds are dispersive: e.g., Asian Openbill

Ringing recoveries show east-west dispersal (Source McClure, 1974) Techniques Numbers

Movement patterns/migration

Habitat use

Effects of management or human use on numbers and usage How to estimate numbers of waterbirds?

Wetland habitats are discontinuous direct counts appropriate, especially when birds are concentrated

•At roosts •breeding colonies •feeding areas Coordinated (simultaneous) counts by teams of observers in larger wetlands Black-faced Spoonbill Platalea minor

2005 Census 1,475 birds Sometimes estimates may be wrong by an order of magnitude!!!

Oriental Pratincole Glareola maldivarum

Wetlands International (2003) estimate was 75,000

BUT 2.88 million were counted in NW Australia in February 2004 (Sitters et al., 2004) Gives estimate of standard error and detectability

Double counting Two observers conduct independent counts at same site Turnover-complicates assessment of the numbers of birds using a site

Staging areas

600 birds

Asian Dowitcher Limnodromus semipalmatus Main wintering area 23,000 birds “Rule of thumb” for migratory shorebirds, estimated migratory population at a site is roughly 4 x the maximum count (Unreferenced and unreliable)

For reliable estimates, capture/recapture methods (e.g., Schaub et al. 2001)

Involves marking of individuals Usage

Usage (bird-days): average of a series of counts x time interval (days)

∑(n1 + n2 + n3 ..... + ni ) x time interval (days)

No. of visits

may provide a more meaningful estimate of usage than just maximum numbers Usage

Useful for comparing among sites at same time of year

But can lead to misjudgement

e.g., passage stop-overs of short duration at staging sites Different populations or subspecies may use different wintering sites/staging areas

How do we identify them?

Red Knot Calidris canutus – 6 different subspecies/flyway populations Capture and marking Mist-nets

Mostly catch at night

Relatively few birds for much effort Cannon-netting

Large catches – up to several hundred birds per firing

Needs large team to process birds safely

Birds need to be on dry-land roosts, e.g., sand- beaches Methods of marking Ringing or banding: used for over 100 years

Numbered metal band applied to the leg of a bird Recoveries of ringed birds build up a picture of origins and destinations.

Ruddy Turnstones passing through UK come from two discrete breeding areas, from Greenland and Scandinavia Colour-marking methods

Enables place of origin of marked individuals to be identified non-intrusively.

One colour combination per flyway site

Ringed in S. Australia A leg-flagged Curlew Sandpiper Resighted Inner Gulf of Thailand, April 2005

7062 km, with a bearing of 316 degrees, from the marking location Leg-flagging

>250,000 shorebirds ringed in Australia 126,000 leg-flagged (since 1990)

•534 recoveries •3903 sightings Radio-telemetry

Often used to study movements of e.g territorial birds that only move short distances Advantage: transmitters are small and light-weight (down to 0.4 g)

e.g, tracking feral /released Painted Storks Satellite telemetry

Advantage: •Can follow birds for long (globe-spanning) distances

Bar-tailed Godwit

10,060-10,200 km non-stop

6.5-7.5 days of flight: New Zealand to Korea & Japan

Longest successful migratory flights tracked Northward migration, 2007

Tagged 16 birds at Miranda and Golden Bay Dr Brett Gartrell, IVABS, Massey Implanting a female Male godwit with solar-powered backpack Later 1 to Japan, Korea LEG FLAG CODES FEBRUARY 2007

RUSSIA CHINA Pale Blue Pale Blue Pale Green Yellow Yellow Green White Black White nothing nothing Black White Orange Black White

Wrangel Isl. NChukotka S Chukotka Kamchatka Sakhalin N Yellow Sea Chongming Dao Chongming Dao

SINGAPORE PHILIPPINES THAILAND INDONESIA AUSTRALIA Green Black Black Black Yellow Yellow Green Orange White Blue Green Orange Orange nothing nothing Green

Singapore N Philippines Inner Gulf Java SW WA NWA QLD NSW

What do birds eat?

Spatial/temporal distribution of prey

Bird distribution and behaviour in respect of above Shorebirds foods: mostly polychaete worms, molluscs, crustacea

Some invertebrate foods of shorebirds Penaeus & Metapenaeus spp.

Orbicularia orbiculata Ocypode spp.

Scopimera spp. usually on sandy substrata

Portunus spp.- swimming crabs Callianassa spp.

Glauconome virens

Oratosquilla spp.

Macropthalmus spp. on muddy sediments

Anadara granosa

Tellina spp.

Corophium spp.

Cerithium spp.

Uca spp.

Natica spp. Gammarus spp. Using a corer to take a mud sample Generally speaking shorebird usage and prey density are correlated How do birds use habitats?

We can measure feeding rates in shorebirds

Human use and bird use often negatively correlated

Feeding rates of Semipalmated Plovers (Yasue, 2005) Red Knot- subspecies rufa Numbers have declined from 51,300 in 2000; to 30,000 in 2004; only 17,200 by 2006

Over-harvesting of Horseshoe crabs by humans Counting methods Direct counts or direct estimates