Abstract:

From July of 2006 to July of 2007, four Great Black headed Gulls (Larus ichthyaetus) installed with PTTs at Qinghai Lake were tracked accomplishing autumn and spring migration and returning to the breeding site. According to the signals received from ARGOS, the first gull left Qinghai Lake on 2nd of August and the last one on 14th of August. The four gulls migrated towards four different directions, and made several stopovers about 200～1 300 km away from Qinghai Lake, with the longest stop of over 80 d before arriving at the wintering ground, Bengal Bay which is about 2 100 km away from Qinghai Lake. The first gull arrived at Bengal Bay on 3rd of November, and the latest one on 3rd of December, and they spent 81～116 d in their migrations. After four months (118～149 d) stay in Bengal Bay, the gulls left the wintering site in succession from the first of March to 30thof March in the next year, and arrived at Qinghai Lake from 23th of March to 17th of April. The results showed the spring migration routes of all the gulls expect for one were different from that of autumn ones. One of them might fly directly towards breeding site, and arrived at Qinghai Lake in 6 d, while the other 3 gulls took 15, 18 and 32 d, respectively. The latest one arriving at Qinghai Lake stopped at the Yellow River of Ninxia for 20 d before coming backed to the Qinghai Lake. Based on the spring and autumn migration routes, some important stopovers sites were determined in the paper.

Key words: satellitetracking;Qinghai Lake;Great Black\, headed Gull;migration;Bengal Bay