Unpacking the fitness consequences of a warmer spring on an overwintering butterfly
Declining butterfly abundance over recent decades coincides with both habitat loss and increasingly warmer springs. Warmer temperatures could pose a problem for ‘capital’ breeders, especially those species that enter winter diapause as a pupa or adult, since a higher metabolic rate pre-eclosion is expected to further deplete lipid stores needed for egg production. We undertook an experiment on Pie