Regional Differences in the Diets of Adélie and Emperor Penguins in the Ross Sea, Antarctica

• Published in: Animals
• Main Authors: Seo-Yeon Hong, Jong-Ku Gal, Bo-Yeon Lee, Wu-Ju Son, Jin-Woo Jung, Hyung-Sul La, Kyung-Hoon Shin, Jeong-Hoon Kim, Sun-Yong Ha
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2021
• Subjects: stable isotope analysis; Adélie Penguin; Emperor Penguin; Ross Sea; SIAR; Veterinary medicine; SF600-1100; Zoology; QL1-991; Antarctic; Terra Nova Bay; Hallett; Cape Hallett; Inexpressible Island; Coulman Island; Cape Washington; Antarc*; Antarctic Krill; Antarctic silverfish; Antarctica; Aptenodytes forsteri; Emperor penguins; Euphausia superba; Pygoscelis adeliae
• Online Access: https://doi.org/10.3390/ani11092681; https://doaj.org/article/9d6ed2eb8bf64b93b9590da89abf2152

To identify the dietary composition and characteristics of both Adélie ( Pygoscelis adeliae ) and Emperor ( Aptenodytes forsteri ) penguins at four breeding sites, we performed stable carbon (δ 13 C) and nitrogen (δ 15 N) isotope analysis of down samples taken from penguin chicks. Adélie Penguin chicks at Cape Hallett mostly fed on Antarctic krill ( Euphausia superba 65.5 ± 3.5%), a reflection of the prevalence of that species near Cape Hallett, and no significant differences were noted between 2017 and 2018. However, Adélie Penguin chicks at Inexpressible Island, located near Terra Nova Bay, fed on both Antarctic silverfish ( Pleuragramma antarctica 42.5%) and ice krill ( Euphausia crystallorophias 47%), reflecting the high biomass observed in Terra Nova Bay. Meanwhile, no significant difference was noted between the two breeding sites of the Emperor Penguin. Emperor Penguin chicks predominantly fed on Antarctic silverfish (74.5 ± 2.1%) at both breeding sites (Cape Washington and Coulman Island), suggesting that diet preference represents the main factor influencing Emperor Penguin foraging. In contrast, the diet of the Adélie Penguin reflects presumed regional differences in prey prevalence, as inferred from available survey data.