Linking population trends of Antarctic shag (Phalacrocorax bransfieldensis) and fish at Nelson Island, South Shetland Islands

CASAUX R.; BARRERA-ORO E.

Tenerife

Workshop; The CCAMLR Ecosystem Monitoring and Management Working Group; 2016

ABSTRACT This document analyses and relates longterm information on population trends of inshore demersal fish and Antarctic shagsof the South Shetland Islands. The analysis iscomplemented with comparable information on diet, foraging patterns andbreeding output of shags from the DancoCoast, western Antarctic Peninsula, an area that has remained out of the influence of thecommercial fishery. Instead of climate change processes, indicated asresponsible for the diminution of other bird populations, the most reliable causeof the declining trend observed in shag colonies at the South Shetland Islandsis the concomitant decrease in the abundance of two of their important fishprey species, Notothenia rossii and Gobionotothen gibberifrons, owed to theintensive industrial fishing in the area in the late 1970s.