Barotrauma in snapper

Barotrauma in Golden Snapper, The Video Explained.

The video shows the immediate response and recovery of released golden snapper (Lutjanus johnii) from various depths. This was a pilot study investigating post release mortality rates and the effectiveness of returning fish back to capture depth (e.g. using a release weight). 
Golden snapper were caught using conventional tackle to simulate capture by the average recreational angler. They were not “winched” to the surface nor were they bought up slowly. All the fish were handled the same before being released into the cage and then returned to capture depth. None of the fish were vented before being returned to depth.
Results
The snapper captured at 8 metres were able to hold position in the water column and move freely about the cage. There were no visible signs of barotrauma associated injuries.
The fish caught from depths of 14 and 23 metres lacked coordination and were unable to regulate their depth within the water column. All fish exhibited visible signs of barotrauma on capture (ie bloated abdomen, everted stomach).
After the experiment fish from different depths were euthanized and autopsied to assess any internal injuries. The combined results of the underwater experiments and the autopsies demonstrated the long term survival prospects for golden snapper caught from 8 metres of water was good, however snapper caught from depths of greater than 10 metres were clearly limited in their ability to swim and escape predation. These fish also suffered potentially fatal internal injuries rendering them highly unlikely to survive release.
Conclusion
Golden snapper are not suitable for catch and release in water deeper than 10 metres due to the effects of barotrauma and should not be targeted just for sport. Catch what you need for a feed and move on.
Watch this space for updates on the project as Fisheries carry out similar research on some of our other popular reef fish species.