In addition to the SNOW BUNTING at Startop's End Reservoir, Tring, mentioned above, the juvenile GREAT NORTHERN DIVER remains at Caldecotte Lake (see Ben Andrew's superb offerings above) and at least two ringtail HEN HARRIERS at Gallows Bridge.
At Calvert Sailing Lake, a juvenile ICELAND GULL roosted last night, with at least 3 CASPIAN GULLS in the roost.