Baleen reveals sex-specific foraging, reproduction and pregnancy endocrinology in sei whales

This dataset contains the hormone concentrations and stable isotope values generated from sequential baleen samples of 11 sei whales (Balaenoptera borealis) stranded in Chilean Patagonia during the 2015 El Niño-associated mass mortality event. The dataset supports the manuscript entitled Baleen reveals sex-specific foraging, reproduction and pregnancy endocrinology in sei whales. It includes concentrations of cortisol, corticosterone, and progesterone (ng/g), together with δ¹³C and δ¹⁵N values (‰) measured from sequential baleen samples. Whale IDs correspond to the individuals described in the associated manuscript, and sample position indicates the distance (cm) from the proximal end of the baleen plate.