A popular belief is that if sharks stop swimming, they will sink and drown. This is only true for some species – it all comes down to the breathing techniques used by the shark.
A few sharks, like the great white and whale shark, need a strong current flowing to their mouths to avoid suffocation; without this water movement, they’d drown.
What Breathing Techniques Do Sharks Use?
Sharks get their oxygen from water using gills. These gills both filter oxygen and remove carbon dioxide from their bodies. The gills work as a filter, letting oxygen enter the bloodstream and circulate through the body.
Sharks have two ways to breathe: by swimming, which forces water over their gills, or by holding water in their cheeks and pumping it over their gills. This latter method, known as buccal pumping, lets them stay still on the ocean floor without drowning.
What is Buccal Pumping?
Buccal pumping involves the mouth opening and closing to move water over the gills. Some sharks have spiracles, a special opening behind the eyes, which help pump water over the gills and prevent debris like sand from entering.
