HFCheung

This autumn seems to be pretty good for Common Tern.  I am quite sure the group of 9 to 10 that we saw in early-August near Tern Island are Common.  Although Common does not breed in HK, it does pass through in good numbers regularly.

HF Cheung

HFCheung

有好照片，可檢查尾尖與翼尖的相對位置，粉紅尾很長，尾尖在翼尖之後。
飛起時 Chunfai 的方法可以，但最簡單可能是檢查背部，普通燕鷗有明顯的白腰。

張浩輝