10 Cool Shark Facts: Your Questions Answered!

bull shark bahamas, bull shark, bahamas
Bull Shark By Albert Kok~enwiki – Own work, CC BY-SA 4.0

The following are 10 Cool Shark Facts in a question and answer format.

1.How many shark species are there?

There are 512 described and 23 un-described shark species (according to Wikipedia)

2. Are sharks vertebrates?

Yes, sharks are vertebrates. Vertebrates have a backbone or spinal column. In the case of sharks, they have a spinal column made out of cartilage, not bone as in other vertebrates like bony fishes.

2.What is a group of sharks called?

A shoal (this applies to other fish as well)

3. What are baby sharks called?
Pups!

5. Are sharks endangered?
At least 143 species are on the IUCN red list with 210 more as data deficient (meaning we haven’t studied them closely enough to know how endangered the sharks are). But all sharks are in danger of becoming endangered due to overfishing, pollution, and other threats facing our oceans.

6. How many millions of years old are sharks?
The first sharks appeared 440 million years ago.

7. Which shark is the smallest? Which shark is the largest?
The smallest shark is the dwarf lantern shark, which grows to 7.9 inches (20 cm)
The largest shark is the whale shark, which can grow up to 60 feet (but is found to be 18-33 feet long on average)

8. Are sharks found in freshwater or saltwater?
Most sharks are found in the ocean in saltwater, but the river sharks are found in fresh and brackish water (slightly salty water) in Asia and Australia. The bull shark is unique in that it can live both in fresh and saltwater in tropical rivers worldwide.

9. Do sharks have swim bladders?
No, unlike the bony fishes, sharks don’t have swim bladders but the oil in their livers help them stay afloat.

And the final cool shark fact is:
10. How often do sharks eat?
It varies greatly between shark species. A great white shark can go a month without food after a full meal.

Also see: 10 Not-so-Scary Tiger Shark Facts

10 Interesting Great White Shark Facts

and Great White Shark’s Adventure at the Monterey Bay Aquarium

Fun quiz on sharks from NatGeoKids

The diversity of shark sizes graphic

Sharks on endangered species list

List of all sharks on Wikipedia

Review of documentary Sharkwater: Extinction by Rob Stewart

Rob Steward
Rob Stewart, award-winning biologist, photographer, conservationist, author and filmmaker

I just watched Sharkwater: Extinction (2018) a documentary that stars shark and ocean conservationist Rob Stewart. It’s the sequel to Sharkwater, which came out in 2007. According to the Sharkwater.com biography on Rob, his documentaries along with his activism, has saved 1/3 of the world’s sharks.

But sadly, I learned that 150 million sharks are killed a year, double the 73 million sharks a year number I heard many years ago. Sharks are killed not just for the shark fin trade anymore—shark can be found in cosmetics as squalene or squalane, in pet food or livestock feed and in the “fish” sold in stores and restaurants. Much of the fish in sold in stores is mislabeled, or in the case of shark intentionally mislabeled (maybe by the distributor or fisherman) so consumers will buy the product. It’s dangerous to eat shark because they are full of toxins like mercury. It’s recommended that pregnant women and children don’t eat shark because of that.

Rob and his cameraman got great footage of two sharks still alive in a gill net, but about to meet certain death. They were not able to save the sharks, but their footage helped convince legislators in California to ban gill nets in 2018. Gill nets can be miles long and are made of a clear monofilament that practically disappears underwater. Large animals such as sea turtles, sharks, whales and seabirds swim into the net and get stuck. All the above animals, except most sharks that need to keep swimming to get oxygen, need air to breathe. These caught animals drown before the fishermen pull the nets up.

Gill nets are used in target fisheries, such as for swordfish. Anything not a swordfish is considered bycatch. According to Oceana, an ocean conservation non-profit, up to 63 billion pounds of bycatch is caught every year and thrown back into the ocean. When Rob made Sharkwater: Extinction in 2016, it was only estimated to be 54 billion pounds. Sadly bycatch numbers are up. As is the sobering possibility that by 2050, there will be more plastic and trash in the ocean than fish.

It’s a sad documentary to watch in general, because much of the documentary is footage of shark fins or dead sharks. But there is enough footage of Rob swimming with sharks to be inspiring. The end is sad because Rob passed away before the documentary was complete, and his death completed it. He had been using a rebreather, which is advanced diving, while scuba diving off of Florida. He was looking to film a sawfish in the wild. A rebreather is great for filming wildlife because it produces no bubbles. Instead the carbon dioxide you breathe out is scrubbed out and you breathe in clean oxygen.

The ending montage made me cry, and not just because Rob had died. It’s his moving words that are inspiring. Thanks to his documentaries, his legacy will live on in shark conservationists worldwide. Please visit Sharkwater.com and read, 10 Easy Ways to Save Sharks and watch on Amazon Prime for free (if you’re a subscriber).

Meet Deep Blue—the Largest Great White Shark Ever Filmed

great white shark
Great White Shark Image by skeeze from Pixabay

The following is about Deep Blue, a Great White Shark most recently filmed in the Hawaiian Islands in January of 2019. She is estimated to be 20 feet long, weigh 2.5 tons, and to be 50 years old. She’ll keep growing throughout her long life. She was last filmed 2,400 miles away off of Guadalupe Island, which is off of Baja California, Mexico in 2013. She also was photographed in 1999.

Aha! I smell it—rotting whale flesh. There’s no smell quite like it. It gets my stomach rumbling, as I haven’t eaten in a month since the last whale carcass I feasted upon.

I can smell blood from miles away. This is necessary in the open ocean. Some dead whales sink and become food for the deep sea life. Thankfully others float, which is where I eat them.

There it is! I’ve found the dead whale. There is a feeding hierarchy, which means the biggest sharks eat first. That means the puny tiger sharks, who had been previously feeding on the whale, sensed me coming and are now gone. They have left me with my own personal banquet!

Great white sharks don’t travel in packs, but occasionally we’ll meet one another at opportunistic feedings such as this. I’ve swum past 2 other large female great white sharks in the area. I’m sure they’ll show up later if they haven’t already eaten.

Mmm, yummy. I open my mouth full of triangular, serrated and sharp teeth and close down on the squishy fat and meat of the dead whale. Blood fills the water around me. Wow, it feels good to have some food in my belly.

I take several more bites, closing my eyes right before I strike. Fortunately this whale can’t bite back and hurt my eyes!

Then some strange creatures show up. They jump off a boat and swim down alongside me. Humans are not on my menu. Not enough fat to even bother with!

Lights flash all around me from the humans. They stay out of my way as I continue to feed. Soon, I’ve gotten my fill of whale flesh. I’ll come back tomorrow when I’ve had time to digest some of the meat.

My belly is so big that I feel like I’m going to burst! I look pregnant, but I’m not right now. I had my dozen pups while I was off the coastal waters. I swim off into the deep blue ocean to digest my huge meal.

10 Tiger Shark Not-So-Scary Facts

notice the beautiful tiger-like stripes on the Tiger Shark photo by Edwar Herrano
notice the beautiful tiger-like stripes on the Tiger Shark photo by Edwar Herrano via Undersea Hunter Group

10 Tiger Shark Facts

1. A tiger shark’s stripes fade as he gets older.

2. Tiger sharks are the second most dangerous sharks to humans (after great white sharks)

3. Tiger sharks eat a variety of animals, including sea turtles (their teeth can crack their shells), seabirds, stingrays, sea snakes, fish, mollusks, crustaceans, small sharks and dead whales.

4. Tiger sharks will eat literally anything. They have been found with garbage, plastic bags, license plates and old tires in their stomachs.

5. Tiger sharks on average grow to 10-14 feet long(3-4.3m) (but can grow up to 20-25 feet long [6.1m-7.6m]) and weigh 850-1400 pounds (386-635 kg)(up to 1900 pounds [862kg]).

6. The only sharks larger than the tiger sharks are whale sharks, basking sharks and great white sharks.

7. Tiger sharks generally live alone, but when they do come together in groups they have a social hierarchy based on size. The larger sharks get first dibs on the food source, such as a dead whale.

8. Tiger sharks are killed for their fins, skin and meat. Their liver has high levels of vitamin A and are used in supplements. Their fins are used in the dish, shark fin soup.

9. Tiger sharks are considered “near threatened” (to extinction) on the IUCN Red List. They are just one spot above of “least concern.”

And the final tiger shark fact is:
10. A female tiger shark’s gestation period is 14-16 months, and she can give birth to 10-82 pups.
Also see:
Meet Deep Blue-The Largest Great White Shark Ever Filmed

Great White Shark’s Adventure at the Monterey Bay Aquarium

For more information: National Geographic’s Tiger Sharks
Shark’s World Information on Tiger Sharks
Tiger Shark Facts

Great White Shark’s Adventure at the Monterey Bay Aquarium

great white shark, Monterey Bay Aquarium
Great White Shark photo by: Cherilyn Chin

Hello, I’m a Great White Shark. My ancestors and I have been roaming the oceans since before there were dinosaurs on earth. We have been the kings and queens of the sea…until now. Humans have made the oceans unsafe for me and my fellow sharks. Not only is the water we swim in dirty with garbage and chemical pollutants, but we are being fished and killed nearly to extinction because of shark finning.

And unlike most fish that are fully utilized, just our fins are cut off. This is because our fins are used in Asia for a delicacy called shark fin soup. To add insult to injury, finned sharks are most often thrown back in to ocean alive to die a slow, agonizing death. What hurts another shark hurts me too, as it is almost unbearable to see a fellow shark alive for days on end, and unable to swim due to missing fins.

Recently, I went on an exciting adventure. I was accidentally caught in a fishing net and taken on board a fishing boat. I was sure I was going to die like many of my friends before me. But I was lucky, and I was taken alive! I first went to a very large outdoor ocean pen where I could swim freely. I was fed fish off a stick. It was quite a treat to not have to catch my own food! How long will this luxury last, I kept wondering to myself.

I was later transported in a large tanker truck to the Monterey Bay Aquarium where I was put into the Open Sea tank. While the fat tuna in the tank looked tantalizing enough to eat, I enjoyed being fed salmon by a pole. I would have preferred to catch my own meals, but it was fun being lazy! I saw many people each day through the aquarium window. I loved the transfixed looks of awe on their faces when I swam past. The flashes were annoying, but luckily they didn’t happen very often (thank you docents!).

I felt myself growing larger each day. One day I sensed one of the yellowfin tuna getting weaker from sickness. Once I smell blood in the water, my primitive instincts kick in and chomp! I bit hard into that tuna. That got many of the marine biologists at the Monterey Bay Aquarium worried that I was getting too big for my britches, as well as too large for the tank.

Before I knew it, I was in a stretcher on my way back to the tanker transport truck. They stuck a satellite tag onto my back so they could track where I traveled in the ocean. The tag eventually popped off and sent information back to the marine biologists that told of my travels. But before the tag popped off, each time I felt the tag as I swam through the open ocean I remembered my great adventure to and from the Monterey Bay Aquarium!

Also see 10 Cool Shark Facts: Your Questions Answered!

For more on sharks at the Monterey Bay Aquarium click here