9 Things You Need To Know About The Hidden Stars Of Shark Week

This Shark Week we will see plenty of the “big three”: the great white, tiger and bull sharks. As important as these are, they are just three members of the shark group, which includes over 400 species — and some of the most amazing sharks in our ocean don’t get as much notice. Tuesday at 9 p.m., “Alien Sharks: Return to the Abyss,” the sequel to “Alien Sharks of the Deep” will shed some light on the mysterious life of these lesser known sharks. This year, the show will Paul Clerkin as he investigates the ocean’s depths to better understand these mysterious fish. Here are just a few things you should know about these hidden stars of Shark Week.

1. Some are not easy to observe.

©Olive Andrews / Via whalesalive.org.au

Deep-sea sharks seem almost alien to us because they’re so deep in the ocean that it’s hard to get there and observe them. The pressure is extremely high, temperatures are very low and only in the last several decades have we had underwater vehicles, robots and submarines that can get down into these depths.

2. Some of them really do look like aliens.

©Dianne Bray / Museum Victoria / Via commons.wikimedia.org

The goblin shark is one of the strangest-looking fish in the ocean — very few specimens have been caught and studied. This species was first found in Japan, but is probably widely distributed in the deep sea. It actually feeds by quickly extending its jaw forward and sucking fish into its mouth.

3. No really, some of them have a saw for a face.

© Elyse Booth/Shutter Fotos / Via shutter-fotos.com

There are several species of shark that have evolved this highly specialized saw-like structure. It is covered in electrosensitive pores that these sharks use to detect prey. All species of sawfish are listed as endangered or critically endangered. They are also listed on Appendix 1 of the Convention on International Trade in Endangered Species (CITES), which prevents their international trade. These unique sharks are at risk from habitat destruction, bycatch in fishing nets and the illegal wildlife trade because their “saw” or rostra, as well as their fins, are highly valued and easily get entangled in fishing nets.

4. In the deep you might come across a “living fossil.”

© Citron / http://CC-BY-SA-3.0 / Via commons.wikimedia.org

The frill shark is very similar to prehistoric sharks and is sometimes referred to as “living fossil.” It is typically never found in shallow water; when it is, it’s usually in distress. Eel-like in shape, and up to 6 feet [1.8 meters] long, these sharks can distend their mouths open and eat things that are more than half their body length.

5. You might see a bonus gill.

© Dan Hershman / Via commons.wikimedia.org

At a glance, the bluntnose sixgill shark looks like other more familiar species. But when you look closer, you see that extra gill, which is a primitive trait in sharks. The sixgill can grow up to 16 feet [5 meters] long and 1,300 pounds and can attack like a great white shark, but with a stronger bite. Though primarily a deep-sea species, some make trips to the shallows at night.

6. Some sharks like it cold.

© One World One Ocean / Via oneworldoneocean.com

The Greenland shark is one of the largest sharks in the world, reaching up to 24 feet [7.3 meters] in length. It is probably the most northern-ranging of shark species, living mainly in deep, very cold water of the high North Atlantic and Arctic oceans.

The species has been found at a depth of more than 7,000 feet [2,130 meters], yet stomachs of some specimens have contained polar bear, pieces of horse and even an entire reindeer. Whether those animals were eaten at the surface or scavenged from the bottom is not known. Though it has a propensity for the icy waters of the north, one specimen was caught last August at a depth of 6,000 feet in the Gulf of Mexico.

7. Some sharks walk.

© Conservation International/ by Mark Erdmann / Via blog.conservation.org

There are nine species of sharks that are known to use their fins to “walk” across the sea floor. Six of those species occur in Indonesian waters, which has made them a source of pride for the local people. The shark above was the most recent one discovered, off the island of Halmahera. The local government and dive tourism industry there are eager to promote and protect it as they see that the species has greater value alive than dead.

8. Some sharks are fancy.

© Jon Hanson / Via Flickr: 61952179@N00

Wobbegong sharks belong to the carpet shark family. Their coloration and unique shape is an example of highly specialized evolutionary camouflage. The lobes on the front of the fish resemble seaweed, allowing it to blend in to its surroundings while hunting.

9. Sharks all over the world are under threat.

© Conservation International / Via conservation.org

Hidden stars or not, we know that all sharks are important to human well-being. They keep the food web in check and are a vital part of healthy fisheries. They boost local economies through ecotourism, have the potential to cure a variety of diseases, are a vital part of the carbon cycle and inspire smart design in items ranging from swimsuits to mechanisms that harness wave energy. People benefit from their presence, and we need to keep studying them in order to conserve them.