Deep / shallow setting

Deep setting is a longline fishing technique where hooks are set below a critical depth, out of range of most bycatch species, but within the range that target species are usually captured. In early trials at sea, deep setting was shown to decrease bycatch of sea turtles. Recent research challenges this finding [2].
 
'Set Your Longline Deep' outlines the technical details of adopting this fishing technique. Deep setting uses a longline boat's existing gear with some slight modifications.
References
  1. Beverly, S. 2004. New deep setting longline technique for bycatch mitigation. SeaNet report number R03/1398. Noumea, New Caledonia: Secretariat of the Pacific Community.
  2. Miller, P. and Domingo, A. 2014. Update on sea turtle bycatch on deep set pelagic longlines in Uruguayan Waters.
  3. SPC. 2005. Set your longline deep:  Catch more target fish and avoid bycatch by using a new gear design.