Ocean of Hope

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

10 Cool Facts about Narwhals

Rare narwhal with two tusks!
Rare narwhal with two tusks!

1. Narwhals are often called the “Unicorns of the Sea” because of their tusk, which is actually a long tooth.

2. Most male narwhals have a tusk, while only some females have one. Some narwhals even have two tusks! Their tusks have over 10 million nerves in them and can be up to 9 feet long.

3. The narwhal’s scientific name Monodon monoceras means “one tooth, one horn.” Males have been seen crossing tusks and it is assumed that they are fighting for females or trying to impress them.

4. The narwhals’ tusks can be used for hunting. They use their tusks to slap and stun fish before eating them. Check out video footage of narwhals hunting with their tusks

5. Narwhals live in pods of 10-100 individuals in the Arctic, but have been seen in pods up to 1000.

6. Narwhals mainly hang out at the surface, but can dive down to 5,000 feet deep (1,524 m)

7. Narwhals feed on fish, shrimp and squid. They are suction feeders that swallow their food whole.

8. Predators include killer whales, polar bears, walruses and native Inuit hunters.

9. Narwhals can grow up to 17 feet long (5.2m) and weigh 4,200 pounds (1,905 kg).

10. Defenders.org says, “Narwhals might be more sensitive to impacts of climate change than the polar bear.” Threats to Narwhals include oil and gas development of the Arctic, climate change, and shipping vessels that cause collisions and noise pollution.

Children’s Book Review: On Kiki’s Reef by Carol L. Malnor and illustrated by Trina L. Hunner

Children's book On KIki's Reef by Carol L. Malnor and illustrated by Trina L. Hunner
On KIki’s Reef by Carol L. Malnor and illustrated by Trina L. Hunner

On Kiki’s Reef (Dawn Publications, 2014) is a delightful children’s picture book about the life cycle of a sea turtle.

Along the way, Kiki meets animals on a coral reef. This book is aimed at lower elementary school grades (4-8 years old). Its ample backmatter will appeal to older children, and to parents who can explain it to their young child.

This book is considered fiction, probably because Kiki has a name and the story is told from her point-of-view in the third person. I would consider it informational fiction because real facts are scattered throughout the 755 word book.

Kiki starts off as a hatchling scurrying to the ocean after hatching on the beach. A page later she is already six years old! This is okay because sea turtles’ life cycles are long (she won’t lay eggs until she’s older than 20 years old) and this is just a picture book!

She “meets” coral, clownfish and the colorful fish (tangs and wrasses) that clean her shell of algae. I won’t give away all the animals she meets, which by the way she never talks to, but she even meets a human diver.

Then the book is over when she lays her eggs on the beach where she was born.

The backmatter includes more information on all the creatures mentioned or pictured in the book, and “Carol’s Teaching Treasures,” which includes the author’s activities for kids, web links and book suggestions.

The backmatter invites repeated readings, as children will be searching for all the critters mentioned.

Overall I recommend this book to all elementary school aged children who want to be introduced to not only sea turtles, but to the other denizens of the coral reef.

Prochlorococcus (Blue-Green Bacteria) are the Earth’s Most Abundant Photosynthesizing Biomass

Prochlorococcus, Prochlorococcus marinus
Prochlorococcus is the most plentiful photosynthesizing biomass on Earth Photo by: Anne Thompson, Chisholm Lab, MIT

That’s right, a bacterium called Prochlorococcus marinus, is the most plentiful photosynthesizing biomass on Earth.

There are a billion billion billion (or trillion trillion) Prochlorococci in all the world’s oceans. They’re not a plant (though they have chlorophyll like plants). They’re definitely not terrestrial.

Prochlorococcus is so small that you could lay 100 of them end-to-end and they would be the width of a human hair!

This important organism was first described by scientists in 1992.

Prochlorococcus is very important to the Earth’s ecosystem. It makes up the base of the food chain in the oceans.

They may account for 20% of the global production of oxygen (1 out of every 5 breaths you take are from Prochlorococci), and they take up to 25% of the carbon dioxide from the atmosphere.

Prochlorococcus is the smallest of the photosynthetic organisms on Earth. It is also “possibly (the) most plentiful genus on Earth,” meaning that there are more Procholorococci than any other organism on Earth.

Photosynthesis is when organisms with chlorophyll (green pigments) take the sun’s energy and produce food for themselves. Usually you think of plants photosynthesizing, but in this case it’s bacteria. In the process oxygen is released as a waste product. In the case of the ocean, oxygen is released from a water molecule.

Procholorococci live in subtropical waters (between 40 degrees N and 40 degrees S) that are nutrient poor (called oligotrophic). They are mainly found in the sunlit surface waters (euphotic zone) of the ocean, which goes down to 656 feet (200 m).

Procholorococci have been around for 3.5 billion years!

Not bad for an organism you probably never heard of until today!

For more information on Procholorococcus visit these websites:

Encyclopedia of Life article on Procholorococcus

PBS article on “Without These Ancient Cells, You Wouldn’t Be Here”

Also see “Krill: The Most Abundant Animal on Earth”

European Eel Life Cycle

European eel by: Felice Supino, Wikimedia Commons
European eel by: Felice Supino, Wikimedia Commons

Hi, I’m a European eel. I was born in the Sargasso Sea. The Sargasso Sea is located in the North Atlantic Ocean, due east of Bermuda. I use the Earth’s magnetic field to navigate, a sixth sense of sorts. When I swim, I sense subtle differences in the Earth’s electromagnetic field so I can sense where I am as a youngster and find the Gulf Stream and other currents. This way I can use the currents to hitch a ride to the west coast of Europe and North Africa.

Eel Life Cycle by: Salvor Gissuradottir, Wikimedia Commons
Eel Life Cycle by: Salvor Gissuradottir, Wikimedia Commons

As a youngster (leptocephali) I’m part of the plankton, the small plants and animals that make up the bottom of the food chain in the ocean. After 7-11 months (up to 3 years) I will become a glass eel. Then I will enter freshwater (or brackish, a combination of salty and freshwater) rivers and become an elver. Then as a yellow eel I will mature into an adult. I’ll spend 6-20 years here. Then I become a silver eel that will make the long journey of 3,107-3728 miles (5,000-6,000 km) back to the Sargasso Sea to breed.

In freshwater streams, yellow eels will eat invertebrates such as mollusks, crustaceans, and even slugs and worms from land! The yellow eels also eat fish, which they can scavenge.

Eels have been kept for 85-115 years in aquariums! Scientists estimate eels average 10-20 years in the wild.

Eels’ blood is poisonous, but their poison is killed by cooking.

American eels are also born in the Sargasso Sea, but they ride the currents to the east coast of North America.