Thursday, 26 May 2011

Injured gulls at Alnwickhill

As I was passing I peered over the wall at Alnwickhill today to see my first colour-ringed gull at the site since the probable Norwegian Common Gull in January. Ring reading is not easy at this site due to the distance to the birds, but with a scope today's orange-ringed Herring Gull would have been straightforward. Unfortunately the scope was at home as this wasn't really a birding trip. I did have the SLR with me so managed a couple of record shots. As I was doing this I could see that the bird was limping and it looked as though the colour ring might be linked to the limp. Looking at the photos now I see that the colour ring has slipped down around the foot and was compressing the toes and preventing them from being splayed open in a normal standing position. Of course, without a closer examination it is not possible to tell whether the ring is causing the problem or whether some underlying anatomical problem has allowed the ring to move into this position.

Either way, and in order to salvage some benefit from this unpleasant observation, I was keen to read the ring combination I dashed home for the scope. Alas, although all other birds appeared to be loafing in the same positions, my quarry had moved. Any hope of relocating it was removed by a kerbside recycling vehicle taking a nearby speed bump at some velocity. The combined crescendo of several tonnes of broken glass and metal being shaken and stirred was enough to cause the entire flock of 200 gulls to flee. Last to move was the Great Black-backed Gull which has been loafing at the site for the last week. As it flew I was given a clue as to why it is hanging around here rather than down at the coast - most of the primaries on its left wingtip have been reduced to broken stumps. (How I hadn't noticed this before is a mystery - maybe it was previously only showing its good side?) Hopefully it will be able to regrow them rapidly, though I am wondering how effective its foraging will be as its flight seemed a little laboured. Certainly it was the first gull to return after the disturbance, which is not what I would expect from a healthy GBBG.

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