I realized last night that I might have a harder time than I expected getting together a complete list of all 375 shark species. I know enough of them to keep me busy for a while though, and give me a chance to put together a list. There are several web sites that already have a number of them listed, so I will probably have to compile my own list based on the pieces of lists already available.
Today I will start with my favorite shark, and probably the most feared shark: The Great White.
Statistics:
• Males reach maturity at 11-13 feet
• Females reach maturity at 15-16 feet
• Their adult weight averages anywhere between 1,500 and 2,400 lbs
• The largest of the White sharks tend to be around 20 feet in length, weighing up to 4,200 lbs
• They are primarily solitary hunters
• They usually prefer colder water
• Found in every major ocean
Hunting:
All sharks are good hunters. It’s what they do. But I am fascinated by what I’ve learned about the White shark’s hunting techniques and abilities. Their hunting is anything but random and mindless. There is a process involved. They are stealthy. They are smart. They hunt using many senses. It is commonly known that sharks can smell blood, but that is only part of it. One of my favorite episodes of shark week was one where I was first introduced to the ampullae of Lorenzini. The ampullae of Lorenzini are located in the nose or front of the face. They are special sensing organs called electroreceptors, forming a network of jelly-filled canals. They help the shark to sense electricity fields in the water. Prey gives off electricity. The sharks can sense that electricity, in combination with the smell of dead fish or blood. They also use their eyesight. Their eyesight is so keen that they can even hunt by moonlight. They can detect sound waves in the water using a sense organ called the lateral line. The lateral line runs down the sides of the shark, on either side of the dorsal fin from the gills to the tail.
A shark will stalk its prey. It will sense it from quite a ways off, and watch it to see what it is and what it might do. If it decides the prey is worthy of a closer look, and potentially becoming a meal, the shark will drop down to the ocean floor, and ambush its prey at speeds of up to 20 miles per hour. It hits its prey from the bottom, with such great force that sometimes the shark (and the prey) will breach the water, making itself visible to anyone around.
Sharks don’t have hands, so they test things out with their mouths. On humans, they usually inflict what is called an exploratory bite. They are checking it out to see what it is, and if it’s food. I believe that a White shark could consume pretty much anything it wanted to, but they are actually more picky eaters. Due to their large size and constant activity, they prefer to eat high-fat meals, such as seals. When they bite a human and realize it’s not a food item, they usually let go. I don’t believe a human could survive a Great White attack if the shark’s intent was to eat.
Gentle Giants
Yes, a shark can kill you. Yes, it can eat you. I don’t believe it prefers to. I believe that, given the right circumstances, sharks will tolerate humans in the water. Below is a clip from an episode of Shark Week, called The Sharkman. Here, Mike Rutzen free dives with a 15 foot female Great White shark, and even hitches a ride on her back. I would suggest you watch it with the sound off, because the music that has been put with the video is menacing, and instead of seeing the beauty of what is happening, might cause some to be dissuaded.
Mike Rutzen taking a ride on a shark
What he was originally trying to attempt is to put the sharks into a trance-like state called Tonic Immobility. A shark’s nose area is so sensitive that the lightest touch from a human hand can cause the shark to go catatonic. It's thought that this is due to the ampullae of Lorenzini. When touched, its body will go limp and it will become completely docile. Once the touch has been removed, the shark will continue on as if nothing happened, and swim on its way.
Sharks Killed
This quote is taken directly from news.mongobay.com:
Between 26 million and 73 million sharks are killed each year for their fins according to a new paper published in the October 2006 edition of Ecology Letters.
Shark fins are used primarily in Asian dishes, such as Shark Fin Soup. These animals are being killed, dismembered, and their bodies thrown back in the ocean, for nothing more than their fins. I am personally disgusted by this fact.
So, there you have it; my first shark blog. I hope you have enjoyed it, and I hope you learned something about these amazing animals.
Sources:
http://en.wikipedia.org/wiki/Great_white_shark#Size
http://www.jawshark.com/great_white_recorded_sizes.html
http://en.wikipedia.org/wiki/Ampullae_of_Lorenzini
http://news.mongabay.com/2006/1003-sharks.html
Today I will start with my favorite shark, and probably the most feared shark: The Great White.
Statistics:
• Males reach maturity at 11-13 feet
• Females reach maturity at 15-16 feet
• Their adult weight averages anywhere between 1,500 and 2,400 lbs
• The largest of the White sharks tend to be around 20 feet in length, weighing up to 4,200 lbs
• They are primarily solitary hunters
• They usually prefer colder water
• Found in every major ocean
Hunting:
All sharks are good hunters. It’s what they do. But I am fascinated by what I’ve learned about the White shark’s hunting techniques and abilities. Their hunting is anything but random and mindless. There is a process involved. They are stealthy. They are smart. They hunt using many senses. It is commonly known that sharks can smell blood, but that is only part of it. One of my favorite episodes of shark week was one where I was first introduced to the ampullae of Lorenzini. The ampullae of Lorenzini are located in the nose or front of the face. They are special sensing organs called electroreceptors, forming a network of jelly-filled canals. They help the shark to sense electricity fields in the water. Prey gives off electricity. The sharks can sense that electricity, in combination with the smell of dead fish or blood. They also use their eyesight. Their eyesight is so keen that they can even hunt by moonlight. They can detect sound waves in the water using a sense organ called the lateral line. The lateral line runs down the sides of the shark, on either side of the dorsal fin from the gills to the tail.
A shark will stalk its prey. It will sense it from quite a ways off, and watch it to see what it is and what it might do. If it decides the prey is worthy of a closer look, and potentially becoming a meal, the shark will drop down to the ocean floor, and ambush its prey at speeds of up to 20 miles per hour. It hits its prey from the bottom, with such great force that sometimes the shark (and the prey) will breach the water, making itself visible to anyone around.
Sharks don’t have hands, so they test things out with their mouths. On humans, they usually inflict what is called an exploratory bite. They are checking it out to see what it is, and if it’s food. I believe that a White shark could consume pretty much anything it wanted to, but they are actually more picky eaters. Due to their large size and constant activity, they prefer to eat high-fat meals, such as seals. When they bite a human and realize it’s not a food item, they usually let go. I don’t believe a human could survive a Great White attack if the shark’s intent was to eat.
Gentle Giants
Yes, a shark can kill you. Yes, it can eat you. I don’t believe it prefers to. I believe that, given the right circumstances, sharks will tolerate humans in the water. Below is a clip from an episode of Shark Week, called The Sharkman. Here, Mike Rutzen free dives with a 15 foot female Great White shark, and even hitches a ride on her back. I would suggest you watch it with the sound off, because the music that has been put with the video is menacing, and instead of seeing the beauty of what is happening, might cause some to be dissuaded.
Mike Rutzen taking a ride on a shark
What he was originally trying to attempt is to put the sharks into a trance-like state called Tonic Immobility. A shark’s nose area is so sensitive that the lightest touch from a human hand can cause the shark to go catatonic. It's thought that this is due to the ampullae of Lorenzini. When touched, its body will go limp and it will become completely docile. Once the touch has been removed, the shark will continue on as if nothing happened, and swim on its way.
Sharks Killed
This quote is taken directly from news.mongobay.com:
Between 26 million and 73 million sharks are killed each year for their fins according to a new paper published in the October 2006 edition of Ecology Letters.
Shark fins are used primarily in Asian dishes, such as Shark Fin Soup. These animals are being killed, dismembered, and their bodies thrown back in the ocean, for nothing more than their fins. I am personally disgusted by this fact.
So, there you have it; my first shark blog. I hope you have enjoyed it, and I hope you learned something about these amazing animals.
Sources:
http://en.wikipedia.org/wiki/Great_white_shark#Size
http://www.jawshark.com/great_white_recorded_sizes.html
http://en.wikipedia.org/wiki/Ampullae_of_Lorenzini
http://news.mongabay.com/2006/1003-sharks.html
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