W is for Whale Shark

Whale sharks (Rhincodon typus)!  Our second aquatic animal on the list!  You may be wondering, is it a whale or a shark?  It is a shark.  But what makes it similar to a whale is 1) it's massive size and 2) it's fondness for plankton.

The whale shark is the largest fish in the world at 9-12m (18-36ft) and weighing up to 12,500kg (27,500 lbs or almost 14 tons).  Whale sharks are typically solitary though they have been seen feeding in large groups.  They are highly migratory animals, traveling thousands of miles.  The reasons behind this travel is unknown, though it is likely due to a search for food.  They generally remain in tropical waters, ranging from 30° to 40° latitude.

Whale sharks are generally quite docile and, as mentioned before, feed on plankton and other small fish by suction filter-feeding.  Females are ovoviviparous, meaning they carry their fertilized eggs until the young hatch inside them and then give birth to live young.  One shark was reported to have 300 fetuses.  Whoah baby!

Not much else is known about these gentle giants, simply because of their habitat and extreme migratory patterns.  What is known, however, is the threat they face from Asian markets.  The recent rise in demand of shark-fin soup could be extremely detrimental to this species.  Based on their size they are likely to be long-lived and slow reproducing animals which could face a rapid extinction if their populations are not cared for.  Luckily some countries have instituted anti-hunting laws and many more have tourism interests that help protect the whale sharks.