An East Anglian population of the seven spot ladybird Coccinella septempunctata was studied to identify factors that influenced overwintering survival. For their body size, individuals that were still foraging in October were significantly lighter than those taken from stable aggregations. Ladybirds taken from aggregations (and hence those that had stopped foraging naturally) suffered just 9% mortality overwinter, compared with 72% mortality in a sample of active ladybirds that were prevented from continued foraging. Even after accounting for their lower relative weight, these active ladybirds suffered disproportionately higher mortality.