Wednesday, October 26, 2011

The Ray

Let me start by saying that sharks, skates, and ray are known as cartilaginous fish because their skeletons are made of cartilage.  You may be wondering what is cartilage.  Well cartilage is the rubbery substance which lines our joints and gives our ears and nose its shape.  Although cartilage is weaker than bone it is strong enough to support some of the largest animals in the ocean.


Cartilaginous fish have many things in common.  Their bodies are covered with rough, sand papery skin and stiff fins that do not fold.  Their jaws are powerful with countless biting or crushing teeth.  Most of these fish are predators, but the largest species are filter feeders.  There are about 600 species of cartilaginous fish living in the sea.  Some lay eggs but many give birth to live young.


What is a Ray? 
I thought this was interesting when I read it.  Did you know that another name for a Ray is a "flat shark"? I read that scientist believe that rays evolved from sharks.  There are more than 150 species of rays, most of which live in the sea. Rays have been around for a really long time, let's say about a 150 million years. They were around when the dinosaurs roamed the earth.  Rays have flattened bodies and wing like fins. They sort of  look like kites. Many live on the seabed camouflaged, but a few spend most of their lives near the surface, flapping through the sea like underwater birds. Unlike sharks, these fish crush their food with blunt teeth. Their mouths and gill openings are on the undersides of their bodies. They have breathing holes on their upper surfaces, just behind their eyes.


Rays are all carnivores. That means that they are meat eaters. They eat fish, crustaceans, mollusks, and worms. Rays mostly hunt on or near the bottom of the ocean. Some are filter feeders, filtering small prey like plankton, small fish, and small crustaceans as they swim. Some rays are also hunters who find prey on the ocean floor.

Now let's talk about defense.  The ray has a super deadly defense against predators.  Many have poisonous spines on their tail which can poison other animals when they are stung. Some rays have long, whip-like tails and others have short tails. Some rays even have thorns on their body to protect it against predators. Rays come in many colors and the colors are different among species and males and females.


Rays come in many different sizes.  They can be a few inches wide to over 23 feet wide. The Short-nose electric ray is the smallest ray and it is the size of a pancake. The biggest ray is the Manta ray and it is 22 feet wide and weighs many tons.

 
 This is the Short-Nose Electric ray.  It really looks like a pancake.



Rays live in the Atlantic, Pacific and Indian Oceans. They are found in both cold and temperate waters and live between 8 meters and 3000 meters below the surface of the ocean. Did you know that it is almost impossible to tell the difference between a skate and a ray because they look so much alike? They are sort of like identical twins, just very hard to tell them apart.

Can you tell which is the ray and which is the skate?  See, I told you that it is almost impossible to tell.

 ray and skate
This is the Skate!                                                This is the Ray!
This is an interesting fact:  Rays were smarter than sharks and are very curious animals.


Differences Between Skates and Rays 

There are a few differences between skates and rays.  These are the major differences.


  • The number one difference is size. Rays can grow to a very large size. For example the manta ray can reach a width of 22 feet and weigh several tons. However, skates range from 16 inches to 5 feet. It is sort of like King Kong and Jane.
  • The second difference is defense.  Well defense is how they protect themselves.  Rays and skates defend themselves differently.  The ray tail has a stinging spine with venom, which it uses as a weapon against predators. However, the skates have large thorns on their backs and tails to defend itself against predators.
  • The final big difference is how they make their young.  All skates lay eggs  however, rays give birth to live young.


My favorite cartilaginous fish is the Manta ray. Also, today I am going to talk about the Manta ray.  It has been very interesting learning about this gigantic sea creature.  I have learned a lot in doing research on the Manta Ray.  Man Ray has given me a picture of himself, for you to get an idea of what a Manta ray looks like. Thanks Man Ray.



                           But that is probably not good enough right, so here is an actual Manta Ray. 



The Manta ray looks like a bird soaring with its wings spread out wide.


The Manta ray has been a part of many legends about sea monsters, but they are totally harmless.  The fact that Manta rays are harmless, is the number one reason that I like it the best out of all the cartilaginous fish in the ocean.  The Manta ray has a wingspan of about 23 feet and it is the largest ray in the world.  Manta rays a huge.  Like many of the largest sea animals, it feeds on plankton.  It scoops up the plankton as it swims.  It has a fleshy paddle on each side of its head to help it funnel food into its mouth.


Check out this Manta ray swimming around and filter feeding.  Look at the open mouth.



Now it is time to talk about sharks and rays.  Sharks and rays are related and belong to the same class.  By just looking at them it is hard to see that they are related but they have a lot of similarities.


This is a shark.                                                 This is a ray.


Similarities and Differences Between Sharks and Rays 

Let's start with the similarities.

Similarities     
  • Rays and sharks both have gills.
  • Rays and sharks both have a skeleton made of cartilage.
  • Rays and sharks both have fins.
  • Rays and sharks have 5-7 gill slits on the sides of their heads and a mouth that usually opens downwards.
  • They have specialized jaws and teeth for different types of feeding.
  • Sharks and rays reproduce by laying eggs or live births.  

Differences
  • Rays are shark do not have the same physical appearance. What I am trying to say is that they look different.
  • Most sharks have long slender bodies but rays have flattened bodies.
  • Sharks use their pectoral fins to lift and steer. However, rays use their pectoral fins to swim.
  • Sharks swim by sweeping their tails from side to side. Rays use their tail for balance or steering.
  • Many ray tails have a sharp barb for protection but shark’s tails do not.
  • Sharks' gill openings are on their sides but rays' gill openings are found on the underside of their head.


I hope you enjoyed reading this post and learned just as much as I did about Sharks, Rays and Skate. Come back to visit my blog.  Hasta la vista!




Monday, October 3, 2011

My Three Favorite Sharks

Today you are going to learn about my three favorite sharks. These are very different and interesting sharks.  They are the Tiger Shark, Thresher Shark and the Blue Shark.   
                                
TIGER SHARK
The first shark I am going to talk about is the Tiger Shark and believe me when I say that it looks nothing like a tiger.  It may have some markings but I would not have called it a Tiger Shark.  So you are probably waiting to see what the Tiger Shark looks like.

Tiger_Shark_1.JPG
These are Tiger Sharks.


  Now this is a tiger.  Do they look alike? 

The Tiger Shark is responsible for more attacks on humans than any other species including the terrible Great White Shark.  The Tiger Shark is a hunter.  The Tiger Shark can be found in tropical and subtropical oceans. They live both inshore and in the open sea.  This shark also has a nickname.  It is called the garbage-can shark, because it is known to eat anything it can swallow.  This is a very greedy shark.  Tiger Sharks have very sharp teeth and very powerful jaws.  It will attack and eat turtles, other sharks, lobsters and even old oil drums.  Tiger Sharks have a striped pattern when they are young but it fades away as they grow.  The Tiger Shark's teeth can go through bone and shell. The Tiger Shark gives birth to live young.  Tiger Sharks can grow up to 25 feet in length and weigh more than 1,900 pounds.

This Tiger Shark was shot at Tiger Beach in the Bahamas having a little afternoon snack. Image credi
Check out how big it opens its mouth!


  
   This is the Tiger Shark's jaw bone.
So you probably have a vision of how aggressive this shark captures its prey. 



Check out this video of a Tiger Shark!






THRESHER SHARK
My second favorite shark is the Thresher Shark.  A Thresher Shark's tail is almost as long as the rest of its body.  The lower part of the tail is small but the upper part is large with a pointed tip.  This is a super powerful long tail which is very dangerous.  They thrash their tails from side to side to round up and wound their prey.  They will even use their tails to hit low flying birds out of the air.  I know that you can't wait to see what that tails look like.  The tail reminds me of a boomerang.  The Thresher Shark is a very good swimmer and can leap clear out of the water.

The Thresher Shark with its long tail.         The Thresher Shark is leaping out of the water.

The Thresher Shark has a short snout and large eyes.  They have small jaws with curved sharp teeth. They come in colors from brown to black with white markings underneath. They can grow up to 20 feet long.  The Thresher Shark eats herring, mackerel and squid. You can find them in coastal waters in warm and temperate areas of the world.  Thresher Sharks give birth up to four live young at one time.  The eggs are hatched inside the mother.  They produce more young but some of its young will eat others while inside their mother's body.  These sharks will eat their own family members.  You would call this cannibalism. 

 
From the front this Thresher Shark looks like a plane that is about to land.

Check out this Thresher Shark feeding.  Look at how it rounds up its prey. 


BLUE SHARK
Now on to my last favorite shark.  This blue fish is one of the most popular sharks in the world.  It is even more popular as a dish.  My mother loves eating fried Blue Shark and I have even tried it myself.  Let me say that I have eaten a lot of better dishes than fried Blue Shark.  There is something about eating shark meat that does not seem right to me.   
This is a Blue Shark.                     Do you want this plate of fried Blue Shark? 

Blue Sharks are easily recognized because of its color, which is blue.  They have very large pectoral fins and are long and skinny looking.  They can grow up to 13 feet long.  They also have sharp triangular shaped teeth.  They feed both inshore and in the open ocean.  They eat many types of fish like herring, cod, haddock, pollock, mackerel, butterfish, tuna and swordfish.   The Blue Shark gives birth to live pups. The litters are about 25 to 50 pups.  The Blue Shark can be found in temperate waters and tropical waters.  They live in the Atlantic, Pacific and Indian Oceans in both inshore and offshore waters.

 Check out this baby Blue Shark being hand feed.

 





 I hope you enjoyed my post and learned a lot.  Until next time.  Adios!!!!