The use of Antarctic shags to monitor coastal fish populations: evaluation and proposals after five years of test of a standard method

This overview reflects the main points of the feasibility of using the Antarctic Shag as a monitor of inshore demersal fish populations, including species of commercial importance. Likewise, the history of the development of this theme in relation to the EMM and FSA Working Groups of CCAMLR since the onset of the 1990s until the recent five year testing period of the Standard Method, is described. Among other conclusions, the analysis of pellets is an adequate method to estimate qualitatively and quantitatively the diet of shags and can reflect differences in fish availability between seasons and areas. Considering the similarities in foraging strategies and reproductive behaviour between Antarctic and sub-Antarctic shags, the methodology proposed could readily be used with other shag species in Antarctica.