New mitigation measures reducing seabird by-catch in trawl fisheries


Leigh S Bull, Boffa Miskell Limited, PO Box 91250, Auckland, New Zealand
Tel.: +64 9 359 2526
Fax: +64 9 359 5300


This paper provides an update on an earlier review [Fish & Fisheries 8 (2007) 31] of mitigation methods used to reduce seabird by-catch in trawl fisheries. Interactions of seabirds with trawl vessels fall into two broad categories: those focused on the trawl warps and those focused around trawl nets. For reducing seabird strikes on trawl warps, the use of bird-scaring lines has been proved to be the most effective mitigation device in the trawl fisheries in which comparative studies have been undertaken. However, the retention or strategic management of fish waste (offal and discards) is recommended as the most effective primary measure for by-catch reduction, and as such should be viewed as the best long-term solution to reducing seabird by-catch in trawl fisheries. Coincident with effective fish waste management, measures such as cleaning the net prior to shooting and reducing the time the net is on the surface should be viewed as best practice measures and incorporated into normal fishing activities. While a number of methods have been trialled to reduce the incidence of warp strikes, there continues to be the need for more work on effective measures for reducing interactions of seabirds with the trawl net.