Seabirds are among the most threatened creatures globally, often due to incidental mortality (bycatch) in fisheries. Several hundreds of thousands of seabirds are thought to be killed worldwide each year by two of the three main types of fishing gear, gillnets and longlines. However, the extent of global mortality in trawl fisheries has remained largely unknown—until now.
A new study published this month (July 2024) in the journal Biological Conservation reveals alarming statistics. The team from British Antarctic Survey (BAS) and RSPB combined bycatch totals from cable strikes and net captures from 25 monitored trawl fisheries and discovered that at least 44,000 seabirds are killed each year.
Seabird bycatch composition by family in monitored trawl fisheries in FAO Major Fishing Areas. Figure 2 from Phillips et al., 2024.
Iconic species underthreat
The most bycaught species were the iconic albatrosses and large petrels, many of which are threatened, in the Southern Hemisphere, and gannets in the Northern Hemisphere. The good news is that a small number of long-term studies indicate that mitigation measures, particularly strategic offal management (particularly avoiding the discarding of fish waste and unwanted catch during trawling), and bird-scaring lines, effectively reduce bycatch rates.
Co-author and bird ecologist Oli Yates from RSPB says: “The long-term solution to this devastating impact has to be more innovative fishing vessel design to effectively manage discards, but in the short-term we need to see companies commit to a rapid adoption of simple, economical and highly effective measures like bird-scaring lines as already championed by a small number of responsible fisheries.”
Urgent action is required. Improved regulations, rigorous monitoring of compliance, and accurate bycatch rate assessments are essential to prevent trawl fisheries from continuing to decimate vulnerable seabird populations.
Read the full article by the British Antarctic Survey here
Incident mortality of seabirds in trawl fisheries: A global review by Richard A. Philips, Emma Fox, Rory Crawford, Stephanie Prince and Oliver Yates is published in the journal Biological Conservation here: Incidental mortality of seabirds in trawl fisheries: A global review – ScienceDirect