Med Gulls Jay House lane

There was 1 adult bird there yesterday morning , but none today at 2.00.There was a ringed LBBGull yesterday it had a large black ring with bold gold letters WCBS .????? The med gull (2nd summer)the day before was ringed with a green ring on the left leg.There has obviously been a movement of gulls through our area from somewhere.?? Also present 3 Stock Dove,2 Skylark,20 Tree Sparrow,200 BH Gull,1 Sand Martin,100 lapwing,2 mallard,20 Linnet,18 Greenfinch,20 Common Gull,70 starling and 5 Pied wagtail.