The Ocean's Gentle Giant: The Whale Shark

When it comes to diving in the ocean most divers have a number of locations and creatures they wish to see with the Whale Shark definitely topping the list. So, what are the facts surrounding the biggest fish in the sea? Let's take a look.

Whale shark: The Oceans Gentle Giant

Swimming with Whale Sharks

As the largest fish in the ocean we may be forgiven for feeling slightly apprehensive about swimming alongside Whale Sharks. As most seasoned divers know the Whale Shark is one of the gentlest creatures you could wish to encounter. Indeed it is a gentle giant of the ocean and is comfortable having a certain amount of human contact presenting no threat to man.

We say a certain amount because it is commonly advised when diving with the mighty Whale Shark divers should adopt an attitude of passive interaction. By this we mean don't go all out to touch and stroke the Whale Shark let the shark approach quietly and decide on whether it wishes to come closer or not. The Whale Shark is non aggressive and will remain so as long as divers do not show aggression towards them.

Physical Features

The world's biggest fish is a cold blooded creature having a skeleton composed mostly of cartilage as most sharks also have. The Whale Shark has an upright tail that moves from side to side when swimming plus breaths through a set of gills. Whales breathe through lungs which highlights the difference between mammals and fish.

Whale Sharks can grow up to forty feet in length, which is phenomenal and can weigh up to nine tons! Whale Sharks love tropical warm balmy locations therefore can be found in waters up to one hundred and thirty metres deep in the Indian Ocean, Mexico and other exotic places. The Whale Shark is easily recognisable as it has a huge wide mouth and is covered in large spots on a darker background. The life span of a Whale Shark is round about seventy years with some scientists believing they can actually live to become centarians!

Diet

Along with the Basking Shark and Megamouth Shark the Whale Shark is a filter feeder. It feeds on plankton, krill, crabs, jellyfish and small fish by taking in water as it swims along then expelling the excess through its gills while keeping the food inside its mouth. It works similar to a giant sieve that sorts the food from the water.

Whale Sharks are said to cough, while this is thought to be a clearing action to expel food build up on the dermal denticles. Whale Sharks don't always find it necessary to move in order to take in water as they can remain stationary and simply suck in huge amounts of water and expel it through the gills just as when swimming.

Whale Sharks Off the Coast of Venezuela

A Mysterious Creature

We say a mysterious creature as scientists have found it difficult to study the Whale Shark therefore information is limited and subject to speculation. The only pregnant Whale Shark caught and studied to date contained three hundred and seven embryos. It is thought that Whale Sharks do not reach sexual maturity until they reach thirty years of age.

Fertilised eggs develop in the womb but feed on the yolk of the egg rather than the host mother. The young are born fully developed, while it is unknown how often Whale Sharks reproduce, mate or where they mate. Based on one female carrying three hundred and seven embryos, if all the embryos survive and are born alive then it looks as if Whale Sharks produce young in high numbers.

Whale-Shark-Rhincodon-Typus

We cannot be sure however about numbers as this is all supposition based on one pregnant female shark. If Whale Sharks do indeed reproduce in big numbers where are they all hiding? There should be huge colonies of Whale Sharks in this case but in reality there aren’t.

Whale Sharks may be spotted all year round in some locations, while in others it is at specific times of the year. It is thought the sharks movements are food driven with the sharks being migratory. It is thought the sexes do not mix unless mating but once again this is unproven therefore is a theory.