Rory lines : silver lining for seabirds in South Africa's demersal trawl fisheries

Seabird bycatch in commercial fisheries is one of the major factors causing decreases in many seabird populations. In trawl fisheries, high mortalities have been recorded as a result of seabirds being struck by trawl warps (the cables used to tow the trawl net). Tori (bird-scaring) lines have been used to decrease seabird mortality in some trawl fisheries by up to 90%. However, tori lines are not effective at reducing the number of birds that drift towards the trawl warps while feeding on factory discards alongside the vessel. The Albatross Task Force (ATF) helped to develop and test a new device, the Rory Line (RL), to be used in conjunction with tori lines, and designed to reduce warp strikes by placing a physical barrier between the scupper (where factory discards are released) and the danger zone (where the trawl warps enter the water) at the stern of the vessel. This study tests the efficacy of the RL at reducing the number of birds drifting into the danger zone and the number of birds being struck by the trawl warps.

Grantor dc:publisher.institution

Department of Biological Sciences

Year dc:date.issued

2012

Author dc:creator

• Rice, Edward

Advisors dc:contributor.advisor

• Ryan, Peter G
• Wanless, Ross M
• Maree, Bronwyn

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/10902

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/10902