Age and feeding habits of Caml grenadier Macrourus caml in Cosmonauts Sea

Macrourus caml is a main by-catch in the Southern Ocean fishery, and a main prey species of Antarctic toothfish, which plays an important role in Southern Ocean ecosystem. In this study, age estimation and stomach content analysis were conducted by using samples collected from the Cosmonauts Sea in 2021. The main objectives of this study were to estimate the age and diet of grenadier Macrourus caml and to explore the feeding habits of Macrourus caml . Stomach content analysis showed that Macrourus caml mainly fed on Malacostraca and Sagittoidea, especially the Malacostraca accounting for over 50%. The feeding habits of male and female Macrourus caml were similar. Before maturation, Macrourus caml mainly fed on Malacostraca and Cnidaria. After maturation, Macrourus caml mainly fed on algae, Malacostraca and Sagittoidea. The feeding bias decreased and the feeding range became wider with aging. The results would provide reference for exploring the nutritional status of Antarctic benthic fish in the ecosystem.