Feeding Ecology of Odontaster validus under Different Environmental Conditions in the West Antarctic Peninsula

• Published in: Biology
• Main Authors: Lisette Zenteno-Devaud, Gabriela V. Aguirre-Martinez, Claudia Andrade, Leyla Cárdenas, Luis Miguel Pardo, Humberto E. González, Ignacio Garrido
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2022
• Subjects: trophic ecology; stable isotope analysis; Antarctic Peninsula; sea star; global warming; Antarctic benthic communities; Biology (General); QH301-705.5; Antarctic; The Antarctic; Nacella; Maxwell Bay; Ardley; South Bay; Ardley Cove; Antarc*; Sea ice
• Online Access: https://doi.org/10.3390/biology11121723; https://doaj.org/article/4374192695f94d39906e97845089d318

To study how Odontaster validus can influence the spatial structure of Antarctic benthic communities and how they respond to disturbance, it is necessary to assess potential dietary shifts in different habitats. We investigated the diets of O. validus from Maxwell Bay and South Bay in the West Antarctic Peninsula. A multifaceted approach was applied including in situ observations of cardiac stomach everted contents, isotopic niche, and trophic diversity metrics. Results confirm the flexible foraging strategy of this species under markedly different environmental conditions, suggesting plasticity in resource use. The data also showed evidence of isotopic niche expansion, high δ 15 N values, and Nacella concinna as a common food item for individuals inhabiting a site with low seasonal sea ice (Ardley Cove), which could have significant ecological implications such as new trophic linkages within the Antarctic benthic community. These results highlight the importance of considering trophic changes of key species to their environment as multiple ecological factors can vary as a function of climatic conditions.