Massive swarms of seven-spotted ladybirds ("Coccinella septempunctata") occurred across the country, with the British Entomological and Natural History Society estimating that by late July 23.65 billion of them were swarming across the southern and eastern coasts of England. The population explosion occurred because a warm spring had meant there were many aphids, the ladybirds' food prey; as the hot weather dried the plants on which the aphids fed, the aphid populations collapsed, causing the ladybirds to swarm to try to find food elsewhere.