What Happens to Deep Sea Fish Brought Suddenly to the Surface?

What Happens to Deep Sea Fish Brought Suddenly to the Surface

The organ called a swim or air bladder helps some deep sea fish to adjust their bodies to different water depths. At great depths, the air bladder contains a tremendous amount of air, but the water pressure prevents it from expanding.

Normally fish move slowly from deep to shallow water and the excess air is absorbed, permitting the fish to be comfortable at different depths. But if a fish in deep water is suddenly brought to the surface, things happen which are most uncomfortable for it. When the pressure of the water that has been holding the gas within bounds is suddenly released, allowing the gas to expand, the stomach of the fish is pushed out of its mouth.

A fish in this condition will usually die if it is tossed back into the water, but if some compassionate person should stick a pin through its side, the extra gas would escape, the stomach would return to its proper position and the fish might swim off none the worse for its harrowing experience