| To monitor the migration dynamic and habitat
utilization of waterbirds breeding at Qinghai
Lake, 3 species 15 birds were installed with PTTs
from July to mid August of 2006. They are 5 Large
Black-headed Gulls (Larus ichthyaetus), 6 Bar-headed
Geese (Anser indicus) and 4 Common Cormorants
(Phalacrocorax carbo).
The PTT for the gulls is 12 gram in weight,
powered with solar battery with 2 years of duration.
The Large Black-headed Gulls were captured in
Quanwan (2 individuals on 10th July), Haixinshan
(2 individuals on 11th July) and Buhahekou (1
individual on 20th July). One of the gulls captured
in Quanwan was found died at Quanwan on 20th
July. The PTT was recollected. The PTTs on other
gulls worked well but the signals received have
prolonged time intervals because the trimmed
feather grew long and covered the PTT, and reduced
the reception of sunlight.
According to the signals received from ARGOS,
the first gull left Qinghai Lake on 3rd August
and the last one in Mid August. The four gulls
migrated to three different directions, and
rested at several stopovers, with the longest
stop of over 80 days. Two of the gulls (ID:
187 and 189) has covered about 1800km and arrived
at Bangladesh Bay (91.738°N, 21.543°E) on 1st
and 3rd of November.
No.187 left for Southeast from Qinghai Lake
on 15th August, arrived at the boundary (35.598
°N, 99.222°E) between Xinghai and Maduo County
of Qinghai Province, and stayed there for 23
days. Then the gull migrated toward southeast
and stopped at Zhaling Lake (35.551°N, 99.172°E)
between Maduo and Qumalai County, where it stayed
for 50 days. Finally, it migrated to the Bangladesh
Bay (91.776°N 22.266°E) on 1st of November.
It's about 300km between Qinghai Lake and Zhaling
Lake, and 1500km between Zhaling Lake and Bangladesh
Bay. It can be concluded that No.187 arrived
at the wintering site of Bangladesh Bay after
79 days, with most of the days spent at stopovers,
especially at Zhaling Lake and the nearby wetland.
No.189 left for west from Qinghai Lake on 3th
August, arrived at Keluke Lake of Delingha City
of Qinghai Province (37.283°N, 96.890°E), and
stayed there for 89 days. Then the gull migrated
to the Bangladesh Bay (91.619°N 24.055°E) on
3st of November. It's about 1800km between Keluke
Lake and Bangladesh Bay. It can be concluded
that No.189 arrived at the wintering site of
Bangladesh Bay after 93 days, with most of the
days spent at Delingha City.
According to the signals received, the other
two gulls were in Xinjiang and Gansu till October.
The recent signals of Common Cormorants received
have been very few, probably because the waterproof
of the PTTs are not very good. 4 of the 6 satellite
tracking Bar-headed Geese have left Qinghai
Lake and still stayed at the Qinghai-Tibetan
Plateau in October.
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