Observer coverage for monitoring bycatch of seabirds and other ETP species in pelagic longline fisheries

Fisheries observers collect vital information for understanding interactions between fisheries, and seabirds and other endangered, threatened and protected species (ETP). This paper presents a review of the levels of observer coverage required to estimate and monitor both commonly and rarely bycaught ETP. Factors affecting the robustness of bycatch estimates and monitoring are also considered.