TOPIC 7 Birds of Wetlands Friday, 9 November 2007 : 08.30 12.00 - - PowerPoint PPT Presentation

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

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 Philip Round Department of Biology, Faculty of Science Mahidol University Rama 6 Road, Bangkok 10400, Thailand frpdr@mahidol.ac.th

Wetlands and Waterbirds

Birds are important bio-indicators

– Conspicuous – Easily identified and counted – Present in virtually all environments/habitats

Convention on Wetlands of International Importance

especially as Waterfowl Habitat Ramsar Convention: Convention on Wetlands

Full title?

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.

Freshwater Rivers Lakes Ponds Canals Marshes Grazing land Paddies Swamp-forests Reservoirs Intertidal/marine Inshore coastal waters and associated rocky islets Sand beaches Mangroves Mudflats/estuaries Brackish-water coastal flats Prawn ponds and fishponds Salt-pans

see Scott and Jones (1995) or http://www.ramsar.org/key_guide_inventory_e.htm

Working classification of wetlands for use in SE Asia

What is a waterbird?

“a species of bird that is ecologically dependent on wetlands”

(Ramsar Convention)

• Combines elements of both ecology and taxonomy
• Definition is broad and not altogether clear

All these species are ecologically dependent on wetlands and may be considered as waterbirds or as “wetland-associated” What is a waterbird?

Ferruginous Pochard This duck certainly is! Manchurian Reed Warbler But what about this warbler? Greater Spotted Eagle Or this eagle?

970 bird species in Thailand 280 are wetland species / wetland-associated Waterbirds

Wetland- associated

(e.g.,kingfishers, some

warblers, wagtails, chats, raptors, etc.)

Waterfowl Wildfowl (ducks, geese and swans) Wading birds

(waders)

Shorebirds

(waders)

Herons, egrets, storks, cranes, ibises etc. Miscellaneous (e.g,

pelicans, cormorants, grebes, rails, etc.)

A classification of terms used with waterbirds

Both sometimes called ‘waders’ or ‘wading birds’!

Order Charadriiformes- shorebirds- eat small benthic invertebrates

• n intertidal mudflats

Herons and egrets- “large wading birds” – eat mainly fish Very different ecological requirements! Mainly resident/dispersive Long-distance migrants

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

• n breeding areas vs., wintering areas

Great Knot

BREEDING AREA BREEDING AREA NON NON-

• BREEDING AREA

BREEDING AREA

Great Knot- world population 380,000

Flyway:

• a route traveled by a group of populations of

migratory waterfowl

• links breeding areas with wintering areas via a chain
• f staging areas
• Orientation mainly N- S

Convenient to subdivide even non-migratory species into flyway populations

Migrant waterbirds:

Wintering areas and staging areas are as important as breeding areas Migrants may spend only

2-3 months on breeding areas

But -

6-7 months in their wintering areas

Staging areas- very important in enabling birds to feed en route- lay down fat reserves to sustain their migration Wintering areas - very important in annual cycle

Asian Dowitcher Limnodromus semipalmatus Use of migratory staging posts “refuelling stops” Main wintering area Staging areas

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: Population estimates upated every three years

• supports an assemblage of rare,

vulnerable or endangered species

• regularly supports >20,000 waterfowl
• supports >1% of the flyway population of a

species

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 Red-naped Trogon Cinnamon-headed Pigeon Phru To Daeng 217 bird species 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.

Melaleuca woodland

A fire-climax following repeated burning of peat- swamp forest Low plant diversity e.g., at Thale Noi Ramsar site, c. 42 km2 of Melaleuca woodland

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

e.g., Pheasant-tailed Jacana Provides shelter and support for feeding and nesting of (chiefly) resident species

Lake margins, swamps and ecotones: emergent vegetation

Purple Heron Yellow Bittern Emergent lakeshore vegetation provides habitat for herons and bitterns

Streaked Weaver at nest Asian Golden Weaver Roosting, feeding and nesting areas for weavers (Ploceidae)

Reedbeds

Eleocharis Typha Phragmites

Sarus Crane- requires extensive areas of seasonally flooded grassland

Phragmites reeds around lake margins and in swamps are a very important habitat for a great range of waterbirds, large and small

Lake margins, swamps and ecotones: emergent vegetation

An ornithologist takes a reed warbler from a mist-net for banding

Black-browed Reed Warbler Manchurian Reed Warbler Reed Warblers, Acrocephalus spp. Acrocephalus bistrigiceps Acrocephalus tangorum

Manchurian Reed Warbler Acrocephalus tangorum globally threatened

Large-billed Reed Warbler: Acrocephalus orinus

Only known from one specimen collected in NW India in 1867 UNTIL one was netted during routine ringing operations at a sewage farm, Phetchaburi, Thailand in March 2006

Where does it breed? Where does it winter?

Maybe in Myanmar?

Distribution by habitat of 4 species of Acrocephalus warblers at Khao Sam Roi Yot during April 1995

Habitat mh netted

tangorum concinens bistrigiceps

• rientalis

n n/mh n n/mh n n/mh n n/mh Pure, mature Phragmites (6 sites) 2706 60

0.022

15

0.01

68

0.025

45

0.016

Marginal (open Typha, young Phragmites) 4 sites 7274

2 0.0003 19 0.003 35 0.005

Pure Typha (one site) 2579 2 0.0008

1 0.0004 6 0.002 13 0.005

Pure Scirpus (one site) 110 1 0.009

3 0.03 1 0.009

Scrub (two sites) 1829

6 0.003 9 0.005

Total metre-hours of net = 14498

Reedbeds are threatened by drainage and clearance:- aquaculture agriculture

Winters only in Philippines

Streaked Reed Warbler A. sorghophilus Breeds where? On migration in E and NE China GLOBALLY THREATENED! HAS ALMOST VANISHED!

e.g. Inner Gulf of Thailand tidal flats 235km2 shrimp ponds 400 km2 salt-pans 106 km2 OFFSHORE HABITAT

Mudflats

ONSHORE HABITATS

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 Black-tailed Godwit Curlew Sandpiper Common Redshank Red-necked Stint Marsh Sandpiper Lesser Sand Plover

HOW MANY? HOW MANY? 19

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

• Used by ca. 2,000,000-3,000,000

migratory shorebirds per year

• 36 shorebird sp. in internationally

important concentrations

• tidal flats ca. 20,000 km2 -

40% already reclaimed

• Plans in hand to reclaim a further

43%

Spoon-billed Sandpiper –perhaps 50% of the world populatiom) Great Knot Calidris tenuirostris 300,000- 400,000 – 90% of the world population

Yellow Sea- Korea & China Mudflat “reclamation”

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

• 304 (59%)– no information
• 32 increasing
• 72 stable
• 96 (19%) declining
• 511 discrete populations worldwide

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)

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 Giant Ibis Lesser Adjutant Sarus Crane

Almost entirely lost!

Kulen Promthep Wildlife sanctuary one of the last extensive areas supporting an intact lowlandfauna

Giant Ibis White-shouldered Ibis Sarus Crane Woolly-necked Stork Black-necked Stork Lesser Adjutant Greater Adjutant Bengal Florican

The lowland bird megafauna

All species associated with grasslands/ponds /open forests of little- disturbed lowland floodplains Most of these species are endangered/critically endangered in SE Asia

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

Painted Stork Spot-billed Pelican Oriental Darter

Better protection at breeding colonies in Cambodia Can use artificial wetland habitats, e.g., fish-ponds, irrigated areas In some cases numbers may be augmented by released captives Fish-eating- benefit from increased aquaculture

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

• Habitat mosaic- always some wet areas

May benefit some waterbirds such as egrets and Asian Openbill Anastomus

• scitans

Area of irrigated rice increased from < 1600 km2 in 1974 to 6400 km2 by 1996

(Source: Molle et al., 2001)

• Loss of the fallow period
• loss in overall biodiversity

driven by reduction in populations of insects and weeds

20 40 60 80 100 120 1 9 8 4 1 9 8 5 1 9 8 6 1 9 8 7 1 9 8 8 1 9 8 9 1 9 9 1 9 9 1 1 9 9 2 1 9 9 2 1 9 9 3 1 9 9 3 1 9 9 4 1 9 9 4 1 9 9 5 1 9 9 6 1 9 9 7 1 9 9 8 1 9 9 9 2 2 1 2 1 2 2 schach cristatus 100 200 300 400 500 600 1 9 8 4 1 9 8 5 1 9 8 6 1 9 8 7 1 9 8 8 1 9 8 9 1 9 9 1 9 9 1 1 9 9 1 1 9 9 2 1 9 9 2 1 9 9 3 1 9 9 3 1 9 9 4 1 9 9 4 1 9 9 5 1 9 9 6 1 9 9 7 1 9 9 8 1 9 9 9 2 2 1 2 1 2 2 Egretta Bubulcus

Shrikes Egrets Changes in abundance of farmland birds around the Lower Central Plain

Insectivorous species have shown a marked decline Egret numbers have remained more or less stable

Cascade of extinctions/effects

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.

1) Ibises, White-winged Duck,

Sarus Crane; mammal megafauna

Cause: low-intensity use, hunting, etc.

• 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).

Rivers present special problems

Blasting of rapids and dam construction on the Mekong River

Coastal areas

Conventionally, most emphasis placed on mangroves BUT very few waterbirds are limited to this habitat Key habitats for shorebirds:

• intertidal mudflats offshore
• extensive zone of low intensity

prawn ponds/salt pans onshore

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

Climate change

Particularly threatening for high arctic nesting waterbirds Global temperatures have increased c. 0.6 C in last 100 years

• more fires

Thawing of permafrost causing drying out of tundra wetlands

Breeding areas Wintering areas

Rising sea-levels Inundation of mudflats Reclamation- construction of sea barriers

Baer’s Pochard Aythya baeri

Disappearing duck!

• Formerly 100+ at several sites in

Thailand (largest count 596)

• No more than 10 have been seen

anywhere in recent years

• 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

2005 Census 1,475 birds

Black-faced Spoonbill Platalea minor

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)

Sometimes estimates may be wrong by even an order of magnitude

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

Mist-nets erected for catching waterbirds

Capture and marking

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 Resighted Inner Gulf of Thailand, April 2005 7062 km, with a bearing of 316 degrees, from the marking location A leg-flagged Curlew Sandpiper

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

• 534 recoveries
• 3903 sightings

Leg-flagging

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

LEG FLAG CODES FEBRUARY 2007

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

(After Howes and Bakewell, 1989)

Make life easy for yourself!

Use a tally counter for large numbers

How many birds?

Actual flock size = 491 birds After Howes and Bakewell (1989)

With practice, counts will usually be accurate within 10%

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

• HOW MANY?

HOW MANY?

n= 21

• HOW MANY?

HOW MANY?

13 n = 36

HOW MANY? HOW MANY?

n = 210 14

HOW MANY? HOW MANY?

15 n= 4000

HOW MANY? HOW MANY? 17 n = 140

• HOW MANY?

HOW MANY? 18 n = 550

HOW MANY? HOW MANY? 19 n = 20,000

Many large waterbirds are dispersive: e.g., Asian Openbill

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

Techniques

Numbers Habitat use Effects of management or human use on numbers and usage Movement patterns/migration

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

• bservers in larger wetlands

2005 Census 1,475 birds

Black-faced Spoonbill Platalea minor

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)

Sometimes estimates may be wrong by an order of magnitude!!!

Double counting Two observers conduct independent counts at same site Gives estimate of standard error and detectability

Asian Dowitcher Limnodromus semipalmatus Main wintering area 23,000 birds Staging areas

Turnover-complicates assessment of the numbers of

birds using a site

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

Usage

may provide a more meaningful estimate of usage than just maximum numbers ∑(n1 + n2 + n3 ..... + ni ) x time interval (days)

• No. of visits

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

Mostly catch at night Relatively few birds for much effort

Mist-nets

Capture and marking

Cannon-netting

Large catches – up to several hundred birds per firing Needs large team to process birds safely Birds need to be

• n 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 Resighted Inner Gulf of Thailand, April 2005 7062 km, with a bearing of 316 degrees, from the marking location A leg-flagged Curlew Sandpiper

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

• 534 recoveries
• 3903 sightings

Leg-flagging

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
• nly be fitted to larger birds

Satellite tracking of Lesser Whitefronted Goose Anser

Satellite-tracking of the Black-faced Spoonbill Platalea minor

10,060-10,200 km non-stop 6.5-7.5 days of flight: New Zealand to Korea & Japan Longest successful migratory flights tracked

Bar-tailed Godwit

GREAT FLIERS!

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

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

LEG FLAG CODES FEBRUARY 2007

Feeding ecology studies

What do birds eat? Spatial/temporal distribution of prey Bird distribution and behaviour in respect of above

Anadara granosa Tellina spp. Cerithium spp. Natica spp.

Some invertebrate foods of shorebirds

Corophium spp. Gammarus spp. Scopimera spp. usually on sandy substrata Macropthalmus spp. on muddy sediments Uca spp. Portunus spp.- swimming crabs Ocypode spp. Penaeus & Metapenaeus spp. Callianassa spp. Oratosquilla spp. Glauconome virens Orbicularia orbiculata

Shorebirds foods: mostly polychaete worms, molluscs, crustacea

Using a corer to take a mud sample

Generally speaking shorebird usage and prey density are correlated

Human use and bird use often negatively correlated Feeding rates of Semipalmated Plovers (Yasue, 2005)

How do birds use habitats? We can measure feeding rates in shorebirds

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

(After Howes and Bakewell, 1989)

Make life easy for yourself!

Use a tally counter for large numbers

How many birds?

Actual flock size = 491 birds After Howes and Bakewell (1989)

With practice, counts will usually be accurate within 10%

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

• HOW MANY?

HOW MANY?

n= 21

• HOW MANY?

HOW MANY?

13 n = 36

HOW MANY? HOW MANY?

n = 210 14

HOW MANY? HOW MANY?

15 n= 4000

HOW MANY? HOW MANY? 17 n = 140

• HOW MANY?

HOW MANY? 18 n = 550

HOW MANY? HOW MANY? 19 n = 20,000