Sinensis Cormorant 27/02/2018

There was a good covering of snow first thing this morning so I decided to go out and enjoy it by giving the dogs an early walk. I took my usual route through Orrell Water Park and was surprised to find the lakes largely free of ice, especially as the forecast had predicted the overnight temperature to fall well below freezing. Anyway the local waterfowl weren't complaining and they had been joined by a couple of Cormorants, one of which was a cracking example of the subspecies sinensis.

While I have seen plenty of sinensis at other sites over the years this is the first one I have knowingly encountered at Orrell Water Park, so it was a patch tick of sorts. The lakes at the park are quite small and cormorants don't drop in that often or stay for very long and when they do it is usually only single birds, so seeing two together and having the opportunity to have a good look at them is quite unusual. I didn't have my camera with me while I was out with the dogs but luckily they stayed around long enough for me to get a few record shots afterwards.

A nice comparison shot of a carbo left and the sinensis right.

While there is a striking difference in extent of the white head plumes of these two birds it is the angle of the gular patch that is a more reliable feature for separating sinensis from carbo. The angle ranges between 38° and 72° in carbo and between 66° and 111° in sinensis (Newson et al). The angle on the white headed bird is clearly more than 90° and confirms it as a sinensis. It is also smaller than the carbo, having a noticeably smaller head and bill and more slender neck, which is typical of sinensis.

It is a smart looking bird.

It looks like it will get cold enough to freeze the lakes over in the coming days and with the whole of the country and much of Europe in the grip of this cold spell it could be an interesting few days. I will certainly be doing my bit to monitor its effects on the birds and other wildlife around here.



References:
Newson, S., Hughes, B., Russell, I., Ekins, G. and Sellers, R. (2004) Sub-specific differentiation and distribution of Great Cormorants Phalacrocorax carbo in Europe. Ardea 92, 3–9