Dear all, On behalf of my co-authors, I am pleased to inform you about our paper titled "Estimation of the feeding record of pregnant Antarctic minke whales (Balaenoptera bonaerensis) using carbon and nitrogen stable isotope analysis of baleen plates", recently published in Polar Biology. The paper is open access, so please download it from this web page: https://link.springer.com/article/10.1007/s00300-021-02816-5 Uchida, M., Suzuki, I., Ito, K. et al. Estimation of the feeding record of pregnant Antarctic minke whales (Balaenoptera bonaerensis) using carbon and nitrogen stable isotope analysis of baleen plates. Polar Biol (2021). https://doi.org/10.1007/s00300-021-02816-5 Abstract Antarctic minke whales (Balaenoptera bonaerensis) are migratory capital breeders that experience intensive summer feeding on Antarctic krill (Euphausia superba) in the Southern Ocean and winter breeding at lower latitudes, but their prey outside of the Antarctic is unknown. Stable isotope analyses were conducted on δ13C and δ15N from the baleen plates of ten pregnant Antarctic minke whales to understand the growth rate of the baleen plate and their diet in lower latitudes. Two to three oscillations along the length of the edge of the baleen plate were observed in δ15N, and the annual growth rate was estimated to be 75.2 ± 20.4 mm, with a small amplitude (0.97 ± 0.21 ‰). Bayesian stable isotope mixing models were used to understand the dominant prey that contributed to the isotopic component of the baleen plate using Antarctic krill from the stomach contents and reported values of Antarctic coastal krill (Euphausia crystallorophias), Antarctic silver fish (Pleuragramma antarcticum), Australian krill spp., and Australian pelagic fish spp.. The models showed that the diet composition of the most recent three records from the base of the baleen plates (model 1) and the highest δ15N values in each baleen plate (model 2) were predominantly Antarctic krill, with a contribution rate of approximately 80%. The rates were approximately 10% for Antarctic coastal krill and less than 2.0% for the two Australian prey groups in both models. These results suggest that pregnant Antarctic minke whales did not feed on enough prey outside of the Antarctic to change the stable isotope values in their baleen plates. Best regards, Yoko -- 三谷曜子 Yoko Mitani 北海道大学北方生物圏フィールド科学センター 海獣班 HokkaidOcean Mammal Team 〒040-0051 北海道函館市弁天町20番5号 函館市国際水産・海洋総合研究センター内219号室 Tel: 0138-85-6558; Fax: 0138-85-6625 Email: yo_mitani@fsc.hokudai.ac.jp Yoko MITANI HokkaidOcean Mammal Team Field Science Center for Northern Biosphere, Hokkaido University Hakodate Research Center for Fisheries and Oceans 20-5 Benten-cho, Hakodate, Hokkaido 040-0051, JAPAN TEL: +81-138-85-6558; FAX: +81-138-85-6625 E-mail: yo_mitani@fsc.hokudai.ac.jp