Wednesday, January 2, 2013

Greenland Shark

Life of Sea | Greenland Shark | Greenland Shark, Although Greenland sharks are not typically aggressive, they are most definitely some of the largest sharks on the planet. While quite a bit of mystery remains regarding this enormous and elusive fish, we have still been able to learn some interesting facts. To give you an idea of just how large they are, Greenland sharks usually grow up to 21 feet (6.5 meters), and they weigh approximately 2,000 lbs (900 kilos)! These usually sluggish sharks have very unique physical characteristics including their varying coloration, interesting fins, and dissimilar teeth. 
An adult can be one or more of a few different colors. These sharks can be slate gray, purplish gray, violet, brown, or black. In addition, the sides of Greenland sharks usually have a purple tint, white spots, or dark bands. In other words these sharks can be great inspiration for designers and artists!Despite the massive sizes of these sharks, they ironically have small fins. Their little dorsal fins are equal in size, situated in the middle of the shark's trunk, and are completely spineless. The Greenland shark's caudal fin is asymmetrical, and although they do not own anal fins, their short, wide tails aid in short acceleration bursts.
Another exceedingly interesting physical attribute unique to these sharks is their eyes. The eyes are very small, and they contain spiracles behind and above them. Unexpectedly, the majority of these sharks are blind due to the fact that they have parasites hanging from their eyes. These pinkish-white parasites are called copepods, and they attach themselves to the Greenland sharks' cornea.
Greenland sharks inhabit freezing waters with temperatures between -2 and 7 degrees Celsius. Interestingly enough, Greenland sharks are the only species that consistently live in these arctic and sub-arctic temperature waters. During the summer months, Greenland sharks spend the majority of their time in extremely deep waters of the ocean; they can be found anywhere from 600 to 2,400 feet (180 to 730 meters) in the depths of the ocean. Contrarily, during the winter months, these sharks enjoy swimming near the water's surface, and can often be found near the edge of ice flows.

Fortunately, this particular species of sharks are no longer commercially harvested. In the past, these sharks were commonly hunted for their livers in Greenland, Norway, and Iceland, however this is not nearly as customary today. Inuit hunters do eat these sharks, but their meat is not a widespread delicacy for a few reasons: they are almost always in freezing waters, and their meat has to be prepared a certain way due to the fact that it is poisonous when fresh. When the sharks travel to rivers such as those in Canada, Canadian fishermen who are harvesting halibut, or other types of fish sometimes catch them. However, we can be grateful for the fact that humans have not caused the population of Greenland sharks to almost completely deplete, which is the case for so many other shark species.

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