Speculating on shorebirds
A contribution by Clive Minton
What an unbelievably exciting time we are having with our Oriental Pratincole satellite transmitter results. No sooner has it gone all quiet and we speculate that all four birds have become relatively static near possible breeding areas than two of the birds ‘explode’ and move long distances in diametrically opposed directions!!
One bird (SUN) flew eastwards and settled on the western shores of Taiwan, near where our only previous report of a flagged Oriental Pratincole had occurred (in 2008). After a couple of days, it then proceeded to the east coast of Taiwan, to an area where only last year Chung-Yu Chiang from the Taiwan Wader Study Group had photographed an Oriental Pratincole nest in the shingle of a large riverbed (Figure 1a. & 1b.).
But then, as if not to be outdone, another Oriental Pratincole (SEP) flew westwards to north-east India and then, after a short pause, onwards to south-west India. Not surprisingly, it is the first Australian-marked wader to be recorded in that region. There is not much land to the west of it so presumably it has now reached the area in which it is going to breed!
Look for water & agriculture
That's where you'll find them
The Oriental Pratincole is 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 now we wait with anticipation for these birds to reveal their choice of breeding sites.
According to reliable location data, SEP and SUN have made significant moves. SUN is now in East Taiwan and data has just been received to confirm SEPs location in South West India (Figure 2.). Chung-Yu Chiang from the Taiwan Wader Study Group, has once again provided information on the habitat of SUN’s current position. While SEC continues to inhabit Cambodia’s “Great Green Belt”, we now believe that SHE may be breeding in the Tonle Sap Biosphere.
Oriental Pratincoles on the move
Somewhere over east
Leg Flag SUN (PTT 83591)
Chiayi County, Taiwan, is where SUN was located from approximately 9th – 12th April, probably hawking for insects over the sugar cane, rice and corn fields that surround the Ba-Chang River. Bad weather in Taiwan over the last week may have affected the performance of the satellite tag, as the next location reading was on 18th April, 132km east of the Chiayi County location in Shoufeng township, Hualien County.
Although the current data positions SUN in the Coastal Mountain Range, it is most likely situated in the vicinity of 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.
SUN is currently approximately 4800km from the 80 Mile Beach release site in North West Australia.
So that’s where you are!
Leg Flag SEP (PTT 83593)
Possibly due to bad weather, or SEP’s constant movement affecting satellite tag performance, we were forced to wait for 15 long days for reliable data to more accurately determine its location.
On the morning of 22nd April, we finally discover that SEP is in South West India in the state of Karnataka, approximately 1220km from its previous site in Odisha. Less accurate data suggests that SEP flew approximately 500km along the coast before heading inland to its current site. SEP is now located on the banks of the Krishna River, within the boundary of Heggur Village, Bagalkot District, Karnataka, where the economy is driven by agriculture and sugarcane fields dominate the landscape.
Lakeside living – a great place to raise a family?
Leg Flag SHE (PTT 83595)
After eight weeks in the Tonle Sap Biosphere, we are now cautiously optimistic that SHE’s movements in this area do suggest signs of breeding behaviour. The tracks are developing a ‘centre point’, which may indicate a nest site. There are some historical breeding records of Oriental Pratincole for Cambodia and in particular other parts of the Tonle Sap Biosphere Reserve and as we have mentioned in previous reports, the area around Tonle Sap Lake consists of floodplains and agriculture, habitat features preferred by the Oriental Pratincole.
Another potential breeding site?
SEC (PTT 83596)
Day 31 and SEC is still in Prey Veng Province; the great green belt of Cambodia, approximately 40km east of Phnom Penh. Is this area suitable for breeding? Time will tell.
The extensive and expensive satellite tracking program we have set up in NWA has only been possible through the efforts and generosity of a large number of people and organizations. It is difficult to know where to start with the formal acknowledgements so I will list them – but not in any particular order of priority.
- The members of the AWSG NWA 2019 Wader and Tern Expedition and similar NWA expeditions in previous years, are particularly thanked for their efforts in the field in catching, banding and deploying transmitters on a range of species.
- Landowners are especially thanked for permission to go onto their property to enable us to catch various species in order to deploy the satellite transmitters. In particular we thank Anna Plains Station for giving us the freedom to roam over large areas of grazed grassland when counting and catching target species.
- AWSG acknowledges the Yawuru People via the offices of Nyamba Buru Yawuru Limited for permission to catch birds on the shores of Roebuck Bay, traditional lands of the Yawuru people.
- AWSG acknowledges the Karajarri and Nyangumarta people for permission to catch birds to be marked for this project on the shores of 80 Mile Beach, traditional lands of the Karajarri and Nyangumarta.
- The cost of the satellite transmitters, which cost around $5000 each, and the satellite downloading costs (around $1000-1500 per month) have been met by a variety of sources. Private individuals (Charles Allen and Doris Graham) have made most generous individual contributions. Kate Gorringe-Smith and her team of artists involved in The Overwintering Project made a large, generous donation from funds raised during their various public exhibitions. The annual NWA Expedition members, collectively, also provided significant funds each year.