News Animals

Why some hammerhead sharks seem to ‘hold their breath’ during dives

These fish may close their gills to stay warm when going deep

A shiver of scalloped hammerhead sharks swim near the surface, in this underwater photograph. These endotherms may thermoregulate by closing their gills as they go deeper.

Scalloped hammerhead sharks off the coast of Hawaii may close their gills to hold on to their warmth when diving hundreds of meters below the surface, new research suggests.

Deron Verbeck

By Freda Kreier

Even fish sometimes hold their breath in cold, dark, deep water.

Scalloped hammerhead sharks living near Hawaii spend their days basking in warm surface waters.