How Whale Sharks Feed

Many people might be nervous of the whale shark and it’s size. At six feet wide and several feet deep, its mouth is literally large enough to fit a human inside. Thousands of teeth, in hundreds of rowst line its lower and upper jaw.  These teeth, however, are smaller than an average humans teeth, and it seems at this time that the teeth are not used in feeding.

If it were a carniverous creature it would definitely cause negative media hype.  However, the whale shark feeds mainly on plankton, nekton, and krill and is commonly referred to as the “Gentle Giant” of the sea.

Plankton passively floats.  Generally microscopic (although jellyfish can be in this classification) plankton can be plant, animal, or algae organisms.  Nekton actively swim.  Usually larger than plankton, nekton are vertebraes, crustaceans, and mollusks that can be found in large aggreggates in the ocean.  Many organisms start as plankton and grow into nekton.  In certain places at certain times, these nutrient rich waters  attract whale sharks either solitarily or in large groups.

Whale sharks are filter feeders.  They actively suck in large amounts of nutrient rich water.  Think over 300 swimming pools worth of water per day.  This water is then forced out of the gills where the plankton is trapped by the “gill rakers” and then swallowed down the, respecitvely, small throat.

Many times the shark will be seen gliding through the water horizontally feeding.  In deeper waters it is likely to see a whale shark vertically feeding.  This is an amazing sight as the whale shark positions itself in the water with its large mouth breaking the ocean surface, remaining in one place and gulping the water.  Occasionally, a larger fish will enter the mouth.  It is then trapped in the gills and the whale shark will “cough” it out.   As the whale shark descends into the blue it may seem to blow bubbles as trapped air from the surface makes its way out of the mouth.  Incredible.



You must be logged in to post a comment Login