Short-tailed Shearwaters have started passing through south-eastern waters of Hong Kong – I had two on Wednesday and one today (Thursday). But the first bird, at about 5pm on Tuesday evening, looked different and was, I suspect, a Sooty Shearwater.
My first reaction on seeing it was – ‘too big for a Short-tailed’. The body seemed large, the wings long and the flight less frenetic than a Short-tailed. Short-tailed look delicate birds – this was stronger looking.
Here are some photos, which I appreciate are fuzzy, but they show some key features
Apart from the general size and shape difference, the following seemed different to me
The white on the underwing was broader, more clearly defined and brighter than any Short-tailed I have seen and had a noticeable dark patch on the trailing edge at the join of secondaries and primaries, which can be seen on the third and last photo above
The body colour was evenly brown, unlike many Short-tailed which show a darker, almost black, head or cap
The forehead was flat, unlike Short-tailed which normally have a steep forehead.
Here is a photo of a typical Short-tailed for comparison
This bird was very similar to the possible Sooty Shearwater photographed by Owen from a boat last year on 25th April
It may be that a few Sooty Shearwaters pass through amongst the early groups of Short-tailed – I am sure watchers on the HKBWS Boat Trips will be on the lookout.