Seasonal trends in adenylate nucleotide content in eggs of recruit and repeat spawning Atlantic cod (Gadus morhua L.) and implications for egg quality and buoyancy

► We examine changes in egg buoyancy and nucleotide content during development. ► Atlantic cod eggs show a marked increase in ATP content at later egg stages. ► Egg specific gravity is turned into lower values at later egg stages. ► Egg buoyancy is a positive function of energy charge, egg size, and egg stage.