A rapid ascent from deep water to the surface means a rapid drop in pressure. That can expand a fish’s swim bladder – the organ that helps a fish control its buoyancy – so much that it pushes other organs aside or even out a fish’s mouth. Scientists have worried that this “barotrauma” might permanently harm a fish, making it harder for deep water fish to survive if they are released. Fortunately, at least one popular sport fish can overcome this trauma.
In Print: December 1, 2014