Changes in serum adipokines during natural extended fasts in female northern elephant seals

•Endotherms rely on adipose tissue to thermoregulate, store fat, and as an endocrine organ.•In Northern elephant seals, circulating adipokines change within fasting periods.•Circulating adipokines are associated with body composition, cortisol, and IL-6.•Adipokines are related to glucose metabolism and insulin sensitivity in seals.•In our wildlife system adipokines had different roles compared to biomedical models.