AWSG North-west Australia Satellite Tracking Project – Summary (Feb-Jun 2019)

This is the fifth year the AWSG’s North-west Australia Wader and Tern Expedition team has fitted satellite transmitters on migratory waders. Five 5g transmitters were put on to Little Curlew with the hope for more success to compare to the previous studies in 2013 and 2015; and five 2g transmitters were, for the first time in history, deployed on Oriental Pratincole. Meanwhile, the two satellite transmitters which were deployed on Whimbrels during the 2017 NWA Expedition are still transmitting.

Photo 1: First Oriental Pratincole fitted with 2g satellite transmitter (by Tom Clarke)

Oriental Pratincole – History in the making (by Grace Maglio)

Prior to 2004, it was thought that the population of Oriental Pratincole in the East Asian – Australasian Flyway was around 75,000 birds. In February 2004, during the annual NWA expedition, participants observed an unprecedented, extraordinary number of this species along Eighty Mile Beach and the surrounding plains and as result a formal count was organised. Through ground and aerial based counts, it was estimated that 2.88 million Oriental Pratincole inhabited the area that year. This was probably due to the plague proportions of grasshoppers occurring at the time and unfavourable weather conditions in other parts of northern Australia.

Catching and banding has been regularly undertaken on Eighty Mile Beach and Roebuck Bay since 1981. Oriental Pratincole have been banded in the hope that some insight into their movements both in Australia and during their migrations and breeding may be revealed. Yet despite over 620 Oriental Pratincoles being marked in Australia over the years, there has only been one recorded resighting, made by Chien-Hua CHEN from the Taiwan Wader Study Group of a bird with a plain yellow flag breeding in Taiwan. As a result of this knowledge gap, we have prioritised studying the movements of Oriental Pratincole.

Normally when one deploys an electronic tracking device on a bird in the non-breeding area, it initially depicts the normal daily home range of a bird as it moves between feeding and roosting areas. This was very much the case with the five Little Curlew, which were fitted with satellite transmitters at Eighty Mile Beach in North-west Australia in mid-February. However, Oriental Pratincoles fitted with similar transmitters on 8 February exhibited markedly different behaviour. These are the first Oriental Pratincoles to be fitted with an electronic device and were particularly targeted because of our almost complete lack of knowledge of their migrations and breeding areas even though they are the most numerous migratory wader to visit Australia from the northern hemisphere in the non-breeding season.

We have been incredibly fortunate in deploying satellite transmitters on Oriental Pratincoles just at the time some were setting off back on their northward migration. The majority arrive in Australia in December and were already known to mostly leave in February, a shorter time than any migratory wader species. Maybe further data will give us some idea of why such an early departure is favored by this species.

Engraved Leg-flag Departure date from Australia (approx.)
SHE 18 February 2019
SEC 26 February 2019
SEP 4 March 2019
SUN 8 March 2019
SEA Transmission ceased 9 February 2019


SHE – First one to depart Australia

 SHE’s first signal away from Australia was detected in the early hours of 18 February. By 23 February, SHE was already enjoying a lakeside view at the largest freshwater lake in Southeast Asia, on the floodplains of the Tonle Sap Lake over 4,000km from the release site. This lake is an important area not only for the flora and fauna of the region but also supports almost 50% of the Cambodian human population, who depend on the lake’s resources.

After ten weeks in the Tonle Sap Biosphere, we are confident that SHE’s movements in this area indicate breeding behaviour. The tracks have developed a ‘centre point’, which indicate a nest site. There are some breeding records of Oriental Pratincole in Cambodia and in particular on other parts of the Tonle Sap Biosphere Reserve.

SEC – Also to Cambodia

After staying ‘close to home’ for just over 2 weeks, (Feb 8 – 25), SEC began its migration around 26th February, via Roebuck Plains, before heading overseas in a more north westerly direction towards Borneo. SEC remained in the West Kalimantan Region, Borneo, for approximately 11 days. Around 12 March there was a brief stopover at Pulau Serasan, (Serasan Island) – part of the southern group of Islands making up the Natuna Regency, Indonesia. Between 14 and 15 March, SEC travelled a distance of approximately 850km to 23km off the coast of the Vietnam-Cambodian border.

From 20 March and 190km from this previous location, SEC was located 40km north east of Phnom Penh in the Prey Veng Province, Cambodia, where agriculture and aquaculture dominate and less than 4% of the original native vegetation remains. SEC has not migrated any further since then, remaining for over 80 days in the Prey Veng Province in Cambodia. This area is known as the “great green belt” of Cambodia due to the plains in the area flooding during the monsoon season (May to October), depositing silts, which drives the region’s high agricultural yields. SEC is probably feasting on the rich insect life in these fertile areas. The lack of onward movement so far suggests that this may be its breeding area.

With all four Oriental Pratincoles left Australia from the north-west by the second week of March to reach Mainland South East Asia by the end of March, it is clear these birds are tracking much further to the west of all our other migratory waders once they have gone past Indonesia.

Fig 1: Tracks of Oriental Pratincole from Australia to Mainland South East Asia – 30 March 2019

However, no sooner had it gone all quiet and we started speculating that all four birds had become relatively static near possible breeding areas, than two of the birds ‘exploded’ and moved long distances in diametrically opposite directions!!

 SUN – History repeats in Taiwan

 Around 6 April after approximately 7 days on Mainland Southeast Asia, SUN headed east and although we are unable to determine the exact route taken, this bird travelled approximately 2,030km to a location in western Taiwan. What makes this flight fascinating is that had SUN taken a more direct route to this area from 80 Mile Beach, Western Australia, it may well have saved itself around 1,000 kilometers of air travel.

Chiayi County, Taiwan, is where SUN was located from approximately 9 to 12 April, probably hawking for insects over the sugar cane, rice and corn fields that surround the Ba-Chang River. This is near where our only previous report of a flagged Oriental Pratincole had occurred (in 2008). Bad weather in Taiwan may have affected the performance of the satellite tag for a week, as the next location reading was on 18 April, 132km east of the Chiayi County location in Shoufeng township, Hualien County on the eastern coast of central Taiwan.

With only inaccurate location data available over the next two weeks we assume that SUN is most likely situated on the dry riverbeds somewhere along the Shoufeng and Hualien Rivers, where breeding attempts have occurred in previous years. Historic breeding records seem to show a preference for dry riverbanks in Eastern Taiwan (and harvested agricultural fields in Western Taiwan).

SEP – The first Australian wader likely to be breeding in India.

Not to be outdone, the fourth Pratincole with a transmitter moves to India. On 22 March, SEP had reached Nakhon Ratchasima Province, Thailand – also an unusual destination for waders spending their non-breeding season in Australia. It was therefore a great surprise when around 1 April, SEP left Mainland Southeast Asia and flew towards India.

On 6 April, SEP was in the coastal plains of Odisha. This is approximately 1,815km north-west of its Thailand location. Unlike the remote and isolated coastal plains of 80 Mile Beach, Kendrapara District, where SEP was located, consists of predominately agricultural allotments (legumes, rice and jute), with many small villages nearby. However, a similarity does exist in the frequent weather events, including cyclones, floods and drought that occur in both regions.

On 22 April SEP took flight again and flew right across the Indian continent to south western India. Here it set up camp on the banks of the Krishna River, within the boundary of Heggur Village, Bagalkot District, Karnataka. It seems to be making short local movements suggesting it is going to breed in that area. Not surprisingly, SEP is the first Australian-marked wader to be recorded in that region and the first Australian wader to be recorded breeding in India.

Fig 2: Tracks of Oriental Pratincole from Mainland Southeast Asia – 28 April 2019

Engraved Leg-flag Distance from 80 Mile Beach release location (approx.)
SUN 4,800km
SEP 6,350km
SHE 4,000km
SEC 3,840km

The Oriental Pratincole, Australia’s most numerous migratory shorebird and is proving to have a very wide breeding range. Breeding populations are reported as occurring from Vietnam in the south to Russia in the north and from Pakistan in the west to Japan in the east.

Their adaptability and ability to utilise modified agricultural land and various water sources most likely contributes to their healthy populations. Yet we have very little knowledge about the movements and breeding habits of Oriental Pratincoles over-wintering in Australia.

With this project so far, we have gained a small but significant insight to their northward movements and their choice of breeding sites.


Little Curlew – The Third Attempt (by Inka Veltheim)

 By comparison, the Little Curlew results are not encouraging. Two of the transmitters have failed before the birds departed from Australia. But we are getting some results from the other three birds.

Photo 2: Little Curlew LS with satellite transmitter shortly before release (by Olivia Gourley)

The first bird to leave Anna Plains was LL, which flew past Roebuck Bay just after midnight on 5 April. It then flew a further 2,000km and landed on the island of Maluku, Indonesia on the morning of 7 April. This track is further east than migration paths of Little Curlews in previous years (2013 & 2015), and may be due to tropical cyclone Wallace tracking across the sea between Australia and Indonesia. Unfortunately, this transmitter has not transmitted since then. It is unclear what may have happened to the transmitter or the bird.

LU, the next Little Curlew to depart Anna Plains, 80 Mile Beach, flew to Guangdong Province, mainland China in one direct, 5,000 km, flight. The last fix of this bird at 80 Mile Beach, Australia, was on 14 April, and the first fix on migration was on 16 April. LU appeared to be also using agricultural fields. About a week after its first stopover, LU moved approximately 1,300 km further north and stop-over in the buffer zone of Yancheng National Nature Reserve.

The third bird LS departed Australia on 23 April. This individual initially flew to Roebuck Plains and back in March. It reached the coast of China on 28 April, having flown non-stop from Australia, similarly to LU. These individuals are about 170 km apart, and LS is near Mianlin, in an agricultural area adjacent to a river.

Fig 3: Migration tracks of Little Curlew LU and LS

Unfortunately, no transmission was received on LS and LU since 14 May. The failure rate for tracking of Little Curlew proved to be high in the 3 years experiences (2013, 2015 and 2019). Different strategy, such as using lighter transmitter, change in attachment method, will have to be carefully investigated if further study is to be pursued.


Whimbrel – Breeding ground reached again (by Katherine Leung)

Both Whimbrel KU and LA reached their breeding ground by early June.

Whimbrel KU was on its 3rd northward journey since we’ve deployed satellite transmitter on it in Feb 2017. This year, it departed Broome on 25 April (3 days later than the previous year) after spending 205 days for the non-breeding season in Australia. KU made stops along its way at Sumbawa Island in Indonesia for a day, and then at Manila Bay in the Philippines for about 4 days. KU used to make a single flight from Broome directly to China in the previous 2 years. The reason why it has changed its tactic is unclear. KU then travelled another 1,033km and landed on Shantou city in Guangdong Province on 6 May. KU’s landing area is more towards the south-west comparing to the previous 2 years. KU gradually “hopped” along the coast of Guangdong Province towards its familiar stop-over site for the past 2 years in Putian, Fujian Province.

LA was a 2nd year young bird when we deployed the satellite transmitter in Feb 2017. It is now on its 2nd northward migration to the breeding ground. LA left Eighty Mile Beach a day later on 26 April (2 days late compared to the previous year) after spending 201 days within a 10km section of Eighty Mile Beach at 40-50km south of Anna Plains Station entrance. LA kept the same practice as the previous year and made a direct 4,901km flight to reach the coast of Fujian Province on 2 May after 6 days. LA spent its time on both Fujian mainland coast and Kinmen Island (outlying island of Taiwan) in the same bay.

Fig 4: KU and LA’s migration tracks and landing locations in Southern China

LA progress sooner than KU and continued heading north to arrive the same stop-over site as previous year in Panjin, Liaoning Province on 15 May. Before KU arrived Panjin, LA has already left and flew north-east to arrive Magadan, Russia on 26 May (2 days earlier than last year). Maximum speed recorded was 48km/h!

KU arrrived at rice paddies area in Panjin on 23 May. KU abandoned its familiar stop-over site 25km south near Yingkou where it has spent 11 and 6 days respectively in 2017 and 2018. Yet KU didn’t stay long at Panjin like the previous 2 years and departed on the same day. As per Liaoning Meteorological Bureau website, rainfall in Panjin and Yingkou had been very low and drought condition had impact on agriculture activities. It is possible that the shallow water rice paddy habitats were not available to these birds this year. KU carried on migrating north and arrived Heilongjiang Province on 25 May.

Fig 5: Stop-over sites around Panjin and Yingkou by the Whimbrels in 2017-2019

LA reached breeding ground less than 24 hours earlier than KU. A few stops were made along the shore of Magadan before LA’s making its final leg of 470km to breeding ground in Chukotka on 31 May. Although LA failed to breed in 2018, apparently it had gained much knowledge about the breeding ground. After reaching Chukotka, LA stopped at two locations where it had stayed last year. We do hope that LA will breed successfully this season.

KU stayed in Heilongjiang for only 4 days before departing on 29 May to Russia. The transmitter captured its departure at 17:00 in the evening with minimum speed of 47km/h. A brief stop-over was made at the boundary of Amur and Sakha on 31 May before KU made a direct 1,516km flight to reach the Arctic Circle, landed only 50km south of its nesting site in 2017 and 2018. Quite likely KU will nest in the same site again.

Fig 6: Whimbrel KU and LA’s migration tracks to the breeding ground

Migration summary of Whimbrels (as of 9 Jun 2019):

Leg Flag

(track colour)

No. of days since

transmitter deployment

No. of days since

departing Australia (2019)

Distance travelled (2019)
KU (yellow) 835 days 45 days 10,191 km
LA (blue) 847 days 44 days 10,719 km


Text Prepared by Australasian Wader Studies Group. More detailed reports found in Australasian Wader Studies Group Facebook Page. 

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