About the Whale Sharks You'll Encounter around Isla Mujeres
The Whale Shark, Rhincodon typus, is the largest living species of fish and the worlds largest shark. However, its popular name is a misnomer since it is not actually a whale. The shark is primarily grey in color with a white underside. Each one is marked with a unique pattern of pale yellow stripes and spots that run the length of its body. Whale Sharks primarily live in tropical warm waters and are generally found in the open ocean. They were only recently discovered to congregate once a year in the summer time nearby Isla Mujeres.
With a mouth up to 5 feet wide and 300 rows of tiny teeth (up to 3000 teeth) they can seem intimidating. On the contrary, they are very docile creatures and pose no significant risk to human beings. They have actually been reported as behaving playfully with divers and snorkelers.
It is generally accepted that Whale Sharks are solitary creatures and only rarely have they been recorded in large groups. This is another reason that the phenomenal gathering of large numbers near Isla Mujeres is an event to been seen and respected.
The Whale Shark is estimated to live somewhere between 60 and 150 years and it is believed to reach sexual maturity at around 30 years. Whale Sharks have been recorded up to 46 feet weighing up to 15 tons. The average Whale Shark is around 25 feet long.
Whale Sharks diet is primarily plankton, algae, krill and sometimes small squid or small fish. They feed by opening their large mouths and sucking in huge amounts of water. The Whale Shark then closes its mouth and begins to expel the water through its gills. Its teeth actually play no part in the feeding process. As the water is expelled a spongy lining along its gills prevent anything but water from passing through. This traps the tiny creatures that make up its diet and allows the Whale Shark to swallow what is left over. Unlike other filter feeding sharks it actively consumes food rather than just randomly filtering as it swims. This is why you can often see them bobbing up and down while trapping their food. One Whale Shark can pass over 1500 gallons of water through its gills every hour.
Whale Sharks are considered to be slow swimmers at around 3 miles per hour. Unlike many other sharks they swim by moving their entire bodies side to side.