August 30th is Whale Shark Day, so now is a great time to learn about the largest fish on the entire planet.
So much like a whale, yet still a shark.
Whale sharks are much more similar to whales, rather than to other sharks, in some ways.
While it’s true that some whales can grow to almost 100 feet long, whales are mammals, rather than fish. Sharks, on the other hand, are fish.
Since whale sharks can measure up to 46 feet long and weigh up to 12 tons, they can grow to be as big as some types of whales. That makes them the biggest fish in the world.
The whale shark has multiple rows of teeth in its gargantuan 5-foot wide mouth, just like other sharks. It doesn’t use those teeth to tear apart its prey the way other sharks do, though.
Instead, whale sharks are “filter feeders”, just like actual whales. Water flows in as they simply open their mouths. Then their bodies filter everything out but the food, releasing water and debris back out into the oceans.
Whale sharks mostly eat plankton, but they will also eat shrimp, sardines, tuna, squid, mackerels, anchovies and more. They must love fish eggs. Whale sharks will patiently wait for as much as 14 hours until fish have spawned on reefs, before swooping in to eat all of the eggs.
In spite of these similarities, whale sharks are not related to whales in any way whatsoever.
The life and times of a whale shark.
Whale sharks can live to be anywhere from 100 to 150 years old, and their childhoods last a very long time. They don’t start having babies of their own until they are around 25 years old.
Unlike most fish, the eggs produced by female whale sharks hatch inside of her, rather than in the water. There is usually about 300 born, but many of them rarely survive to maturity.
Most whale sharks prefer warmer waters and tend to stay in tropical areas around the world. Only about 25 percent of them are in the Atlantic. The remaining 75 percent are in the Pacific and Indian Oceans.
These giant fish spend most of their lives out in the open sea, which makes it extremely difficult to study them. In fact, no one has ever seen whale sharks mating.
Although whale sharks tend to be solitary creatures, they don’t seem to mind feeding in groups with other whale sharks. Fortunately, young male juveniles will cluster to feed in some coastal waters, which is the only place researchers usually get to study them.
The backs and sides of whale sharks are brown to gray, featuring pale stripes and white spots, with a white belly. The pattern of spots on each one is completely unique, similar to the fingerprints of humans.
They have flattened heads and a blunt snout above the mouth. Strangely enough, whale sharks have short whisker-like sensory organs called barbels protruding from their nostrils, just like catfish.
Most sharks use only their tails to swim. Whale sharks, however, move their entire bodies from side to side. They don’t swim very fast, rarely achieving speeds higher than about 5 kilometers per hour.
Save the whale shark!
Whale sharks are very docile animals, and they don’t pose any real threat to humans, which is why it is so sad that they are now an endangered species. Advocates for whale sharks request that people behave responsibly when swimming with them, and donate to non-profits devoted to their welfare.
Also, don’t forget to celebrate Whale Shark Day!