Video: Gulper shark excluder device in action
Video uploaded by ‘SouthEastTrawl’ on 09. December 2015 :
Harrisson’s dogfish and southern dogfish are part of a group of sharks called Upper-Slope Dogfish or Gulper Sharks. To rebuild populations of gulpers a number of fisheries closures have been put in place. These closures are equivalent in area to about 25% of total dogfish habitat available in the fishery. Many of these closures overlap with grounds where royal red prawns are caught in the South East Trawl Fishery off Sydney.
In early 2014 SETFIA announced that it would trial a grid that aimed to catch royal red prawns but exclude gulpers. The project team commissioned something they named a Gulper Exclusion Device or GED. These are widely used in other Australian prawn fisheries.
A GED is an angled aluminium grid in the net that will deflect gulpers and other large fishes up and out of the net unharmed, while the smaller royal red prawns pass through to be caught. Underwater cameras were used to understand how gulper sharks and other larger fishes are ejected from the trawl net (see video taken at 500m).