Aerial view of a dense flock of Great Cormorants (Phalacrocorax carbo) resting on a sandbank at Scroby Sands along with a mixed species flock of gulls including Greater black-backed gulls (Larus marinus), Lesser Black-backed gulls (Larus fuscus) and Herring gulls (Larus argentatus) Great Yarmouth, Norfolk, UK, January 2011.