10 Questions About Sharks Answered

1. 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!

4. How many shark species are there?
There are 512 described and 23 un-described shark species (according to Wikipedia)

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.

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.

Fun quiz on sharks from NatGeoKids

The diversity of shark sizes graphic

Sharks on endangered species list

List of all sharks on Wikipedia

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Book Review: Escape Galápagos by Ellen Prager

Escape Galapagos book cover

Escape Galapagos by Ellen Prager

Escape Galápagos by Ellen Prager is a middle grade adventure novel. It’ll appeal to most nature and animal lovers, but because the protagonist is fearful of wild animals and being in nature, it also has a wider appeal.

It’s like taking a virtual trip to the Galápagos Islands, which are located west of Ecuador in South America. These are the islands made famous by the naturalist Charles Darwin, who came up with the theory of evolution.

The protagonist, Ezzy, is afraid of wildlife and dislikes being in nature. Her dad (never named) and her younger brother, Luke, are the total opposite. Ezzy and Luke’s mother (an adventurous woman) passed away and their family is on a quest to complete her “wonder list,” a bucket list of places she always wanted to travel to. The Galápagos Islands were first on that list.

Ezzy’s fears of wild animal poop, and of being attacked by wildlife are addressed with humor realistically. A major portion of the book is a hike through one of the smaller islands, Española. It was like I was on the hot and sweaty hike through the island. Animals I had heard of, like blue-footed boobies and Galápagos tortoises, were mentioned as well as those I never thought of being there like locusts (described as huge grasshoppers).

The excitement in the books starts about halfway in when the small cruise ship Ezzy’s family is on gets hijacked. I’ll leave it a surprise why they were hijacked, but it’s for plausible reasons.

It leads up to the climax where Ezzy, Luke and Aiden (a boy Ezzy’s age), are in a race against time to cross one of the islands. Their father is stuck on the boat with the hijackers, and to boot, a volcano on the island has just erupted.

The ending was exciting and a good end to a great middle grade novel. I would recommend this book to any lower middle grader (grades 4-6), especially those that like adventures and/or natural wonders.

Will the Galápagos Islands be on your bucket list after reading this book? They are still on mine!

Ellen Prager has also written another series of books called, “Tristan Hunt and the Sea Guardians.” The first book is called The Shark Whisperer, which is about a boy who can “talk” to sharks. He ends up at a camp for those with special sea abilities (like camouflaging). I will review that book in a future post!

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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).

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Meet the Pink Manta Ray!

pink manta ray, manta ray Australia

Pink Manta Ray from Australia photo by Kristian Lane/Instagram

Yes, I’m really pink. My belly is pink, whereas in “normal” manta rays their belly is white with black spots and splotches on it. I’ve been nicknamed “Inspector Clouseau” from the movies and tv program called the Pink Panther. You clever humans!

Why am I pink? I don’t know, I think I was just born that way. You intelligent humans have ruled out stress. From a small skin sample (a biopsy) they have ruled out a diet full of red food, it’s not an infection or genetic mutation.

So now you humans guess that it’s a “unique expression of melanin” or my pigments in my skin are just “off”. Duh, I could’ve told you that! After all there are “strawberry blonde leopards,” and “fuchsia grasshoppers,” due to something called erythrism. That causes animals to appear reddish or pinkish.

I was first seen in 2015 off of Australia’s Lady Elliot Island. I’m now 11 feet wide (wingtip to wingtip) and yes, I’m a boy. I was last seen as part of a courting train, which is when a line of males (in this case 8) chases a female to try and mate with her. Her pheromones are quite irresistible! If she’s looking for unique, I’ve got all the other boys beat!

Even though I stand out in a crowd of manta rays, I’m relatively safe from killer whales and great white sharks due to my size. In fact, my biggest potential predator is you humans!

Yes, all manta rays are at risk at being targeted and hunted by humans. Fishermen nicknamed us devil rays because our curled up head fins look like devil horns. We would often get tangled in their fishing nets and ruin them. They really didn’t like that or us.

Now us manta rays are being targeted for our gill rakers. They are thin, comb-like strings on our gills that capture all the yummy plankton from the water I strain through my gills. In other words, my gill rakers keep me alive!

Unfortunately, a new not-so-traditional controversial formula of Traditional Chinese Medicine utilizes gill rakers and humans now target us gentle and giant beings. We manta rays have the largest brain-to-body ratio of any fish, but alas, even our intelligence can keep us from being hunted, possibly someday to the point of extinction. Coupled with our lack of defense (we have no stingers) we have little hope of surviving unless humans stop targeting and killing us faster than we can reproduce. Its no wonder females have a train of males trying to court them—they only mate every two years and have pups every 2-5 years.

For more on how you can help manta rays, visit these conservation non-profits:

Manta Pacific Research Foundation

Manta Trust

Marine Megafauna Foundation

Wild Aid’s Manta Ray Program

Articles used in this blog post:

Rare pink manta ray spotted near Australia’s Lady Elliot Island

How manta rays gill rakers filter water without clogging

Manta ray reproduction

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Duffy the Sea Turtle: Children’s Picture Book Review

Duffy's Lucky Escape children's book

Duffy’s Lucky Escape children’s picture book

“Duffy’s Lucky Escape,” by Ellie Jackson and Liz Oldmeadow, is a children’s picture book about a sea turtle. She lives on a colorful coral reef. Duffy was minding her own business when a storm came and washed her out to sea. There her adventure with trash in the ocean began…unknown to her she eats some plastic (sea turtles often mistake plastic bags for jellies). Fortunately she is rescued, rehabilitated, and eventually released back where she belongs.

“Duffy’s Lucky Escape” is based on real events. It is a charming children’s book that gently teaches kids about garbage in the oceans and the dangers that it poses to wildlife.

The illustrations are beautiful and colorful. They are realistic, but still cartoony as you’d expect from a children’s picture book. There are facts about sea turtles at the end as well as ways children can help ocean wildlife such as Duffy. For instance, everyone can use less plastic by using a reusable water bottle instead of single use water bottles and also not use plastic straws.

I highly recommend this book for any school-aged child—it would make a great addition to any library. It teaches in a gentle way, and it has actionable tips so children feel empowered to help ocean wildlife.

There are other Wild Tribe Heroes books. “Marli’s Tangled Tale” is about a puffin who gets tangled in a balloon from a balloon release. Another is “Nelson’s Dangerous Dive” about a whale who gets trapped in fishing nets. A newly released book is “Buddy’s Rainforest Rescue” about an orangutan and palm oil.

For more information, visit Wild Tribe Heroes

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