Farmoor Roost

21:40 25 common Terns roosting on eastern most floating perch line on F1. Minimum of 3 Yellow-legged Gulls; 10 plus L B-b 's; 1 adult Common Gull and c1000 B H Gull's. Redshank and Oystercatcher both heard only. Pied wagtails numbers building now.. c 40 plus? in SE of f1 around 8pm Only <10 Swift. All in all very quiet although the mobile red van Bird observatory may have seen more.....