Monday, October 24, 2016

Yelloweye rockfish barotrauma and reflex impairment after capture in shallow and deep water

Yelloweye rockfish, Neil McDaniel
Rankin et al. 2016 report on barotrauma and reflex impairment observed for recompressed yelloweye rockfish in situ. They evaluated orientation, reaction to noise and motion stimuli, and visual and swimming capability. 
Behavior of recompressed fish. Top fish, presence of orientation and vision-dependent movement. Bottom fish, absence of vertical orientation in live fish. Rankin et al. 2016
The authors conclude, “Recompression is a valuable treatment for discarded rockfish that would otherwise be too buoyant to return to depth without assistance. However, the loss of reflex actions as basic as vertical orientation, along with the evidence we found of visual compromise in deep-dwelling recompressed yelloweye rockfish, is concerning, as are the long-lasting physical injuries and lack of neutral buoyancy observed in the weeks after capture and recompression. At a minimum, these effects indicate limits to a rockfish’s ability to move effectively, find refuge, and avoid predators upon release.
The findings from these two studies, which reveal severe and lasting injuries, as well as behavioral compromise of recompressed deep-water yelloweye rockfish, reinforce the importance of avoiding fishing contact with deep-dwelling yelloweye rockfish and maintaining spatially-managed rockfish conservation areas closed to fishing.”

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.