Friday, 2 October 2009

Whooper Swan (Cygnus cygnus) - Latimer, Bucks. 01/10/09

News was put out on the Bucks Birders Yahoo Group that LGRE had just seen 2 Whooper Swans flying over whilst he was in his garden, he noticed that they were descending and headed off in his car to track them down. By 12:22 he had relocated them at Latimer 'Great Lake' where they began washing, drinking and bathing with the resident Mute Swans, Lee put the news out giving everybody the chance to see this excellent addition to his recording area and of course a good Bucks county sighting. It then transpired that one of the Swans had an orange staining to it's plumage indicating that they could well be true wild Swans and not feral or captive birds, I didn't hesitate and headed off towards Latimer in search of the Whoopers.

I arrived on site with no sign of anybody else and headed off on foot, after heading the wrong way and ending up in a woods and then what seemed like somebody's back garden I phoned Lee to get the directions, he kindly directed me where to go and asked me to get some photos especially of the stained bird. I could see the Whoopers in the distance from where I was standing and could hear the odd trumpeting call so I knew they were still present.

When I finally caught up with them both Swans were resting and they soon tucked their heads under their wings to sleep. They slept while floating gently with the current and then swam back upstream and put their heads down again to repeat the process, the odd passing Mallard or Mute Swan would startle them and they became very wary lifting their heads and looking around before sleeping again. Both birds looked tired and slept for most of the time I was there which presumably indicates that they had been on a long journey.

Both Swans were adults with one showing a distinct staining to the head, neck, breast, flanks and belly which is caused by a high concentration of iron oxide deposits in the water and soil on their breeding grounds, when the Swans depart their upland breeding grounds and return to their wintering sites this staining does eventually wear away.

With a number of feral Whooper Swans in the UK it can be very difficult to pin-point the exact provenance of some birds, a number of feral birds do commute between Bedfordshire and the Tring Reservoirs. The orange staining doesn't seem to be found to such extent in feral birds and is often brown in colour from mud rather than iron-ore deposits, it's usually fainter as well. In my opinion the staining to this individual and the fact there was massive movement of Whooper Swans entering the Uk at the time gives a good indication that these are probably genuine wild Whooper Swans.

1 comment:

Bob Bushell said...

Nice shots Ashley, that's amazing to see them at this time of year. Still, they will migrate here soon.