Seabird mortality associated with ice trawlers in the Patagonian shelf: effect of discards on the occurrence of interactions with fishing gear

摘要: This study investigated the level of seabird mortality caused by domestic trawl fleet (freshies) for hake (among other less important targets) operating in waters off central Patagonia (37–48°S), analyzing effect environmental and operational variability on interactions. With a total 135 vessels, is one largest Argentina. Specifically tasked observers were placed onboard trawlers during summer winter seasons years 2006 2007. The type number interactions (i.e. contacts with fishing gear) recorded shooting hauling operations, covering 72 days observation 328 trawls. Black-browed albatrosses, white-chinned petrels Procellaria aequinoctialis, southern giant Marconectes giganteus royal albatrosses Diomedea epomophora most abundant species interacting trawlers. Confirmed mortalities black-browed result collisions entanglement warp cable while birds scavenging. estimated rate was 0.017 h−1 0.105 per vessel day. intensity (in terms unit time) largely explained distribution effort. Seasonality incidence discards strongest factors explaining occurrence annual under investigation roughly to be from several hundred over thousand albatrosses. However, these figures should considered preliminary due limited spatial temporal coverage data fact that estimations based low observed mortalities. implementation strategic discard management may significantly reduce cables or improve effectiveness complementary mitigation methods. Urgent measures needed this along Patagonian shelf.