Nad is back to the coastal highway
We
are amused by the very different migration tactics of Nad (LLJ) and Charlie
(LLK). These two birds departed Broome on about the same date but are now more
than 1,300km apart on the China coast.
After
spending 3 days at the inland area, Nad is now back to the coast in southern
Bohai Bay in Hebei Province. Besides using the mudflat area, it is also
utilising some aquaculture ponds at the coast presumably as high-tide roosting
area.
Fig.1 Nad’s (blue) and Charlie’s (orange) movement in Mainland China |
While Nad has already
travelled another 1,800km in China, Charlie (LLK) has only made one third of
the distance in the same period of time. It is progressing slowly along the
coast of Guangdong and Fujian Province.
Unfortunately
our worst fears have been realised, with yet another transmitter ceasing to
send signals. Mymi (LLH) last sent a signal on 23th April at the South China
Sea, just 250km away from the China coast. At that point she had flown for 5
days since she had left Broome on 18th April and had covered 4,200km at
approximately average speed of 36kms per hour.
It
could be that she was adversely affected by the strong depression which was at
the south China coast at the time she disappeared. But the cause of failure
could well have been the same mysterious problem which affected most of our
satellite transmitters on Little Curlew last year and also Ecosure (LLA) last
week. One theory is that at the end of a long non stop flight birds become so thin
that the harness holding the satellite transmitter on the birds back become too
loose, allowing the transmitter to fall off.
We
will continue to hope that there is some other cause (eg. shortage of solar
power) and that these two transmitters start send signals again in the near
future.
Now
we have only 2 eggs left in the basket. Let us hope that Nad and Charlie (and
their transmitters) do survive and tell us most of all what we want to
know; where our Grey Plover actually breed and what route they actually use to get there from the Yellow Sea.
The migration route of our birds: Ecosure (white), Mymi (red), Nad (blue) and Charlie (orange)
|
The Grey
Plover project team:
Katherine Leung
Clive Minton
Ken Gosbell
Chris Hassell
Grace Maglio
Inka Veltheim
Maureen Christie
29 April 2016
Hi, Great work! I would like toknow which transmitter are you using? Weight & Brand
ReplyDeleteYou'll need to check with the Australian Wader Study Group for those details Igor.
Delete