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Tuesday 13 September 2016

About Sharks

Hi my name is luke and I am going to tell you, want I know about sharks
There are more than 465 known species of sharks living in our oceans today. Sharks are an apex predator at or near the top of their marine food chains, and they regulate the populations of species below them. Research has shown that massive depletion of sharks has cascading effects throughout the ocean’s ecosystems.
Shark, © Ridlon Kiphart
Sharks belong to a family of fish that have skeletons made of cartilage, a tissue more flexible and lighter than bone. They breathe through a series of five to seven gill slits located on either side of their bodies. All sharks have multiple rows of teeth, and while they lose teeth on a regular basis, new teeth continue to grow in and replace those they lose.


Shark ‘skin’ is made up of a series of scales that act as an outer skeleton for easy movement and for saving energy in the water. The upper side of a shark is generally dark to blend in with the water from above and their undersides are white or lighter colored to blend in with the lighter surface of the sea from below. This helps to camouflage them from predators and prey.

Most sharks are especially active in the evening and night when they hunt. Some sharks migrate over great distances to feed and breed. This can take them over entire ocean basins. While some shark species are solitary, others display social behavior at various levels. Hammerhead sharks, for instance, school during the mating season around seamounts and islands.
Some shark species, like the great white shark, attack, and surprise their prey, usually seals and sea lions, from below. Species that dwell on the ocean floor have developed the ability to bottom-feed. Others attack schooling fish in a feeding frenzy, while large sharks like the whale and basking sharks filter feed by swimming through the ocean with their mouths open wide, filtering large quantities of plankton and krill.


4 comments:

  1. Thank you for all this information about sharks, Luke. Where did you find out this stuff? It would be good to include in your post the places you went to to gather your information.

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  2. Hi Luke
    Thank you for posting about sharks. I also like sharks but I am scared of them. Have you seen a real shark?
    Kind Regards
    Mana

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  3. Hi Luke,

    It looks like you know a lot about sharks!

    Most sharks species will drown if they stop moving. Great white, mako and salmon sharks don't have the muscles they need to pump water through their mouth and over their gills. As long as they keep swimming, water keeps moving over their gills, keeping them alive.

    What sort of sharks are your favourite?
    Will you ever swim with sharks?

    Laura,
    Yaldhurst Model School

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  4. Hi Luke,

    I like the research you did on sharks, also for added information, include that the sharks are declining because of overfishing and they are caught for their fins so they can produce shark fin soup, which is both sad and bad.

    looking forward for next blog post
    Jacob,
    Yaldhurst model school

    ReplyDelete

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