Sharks

Did you know that?

  1. Sharks are older than the dinosaurs - With fossil records dating back 455 million years, sharks have outlived the dinosaurs and many other forms of life currently on Earth.
  2. Whale sharks are the biggest fish in the ocean - They can grow to 12.2 meters and weigh as much as 11 metric tons.
  3. Sharks have a 6th sense - Not only can sharks see well in dark lighted areas, have fantastic night vision, and see colors they also have special electroreceptor organs (small black spots near the nose, eyes, and mouth, called the ampullae of Lorenzini) that allow sharks to sense electromagnetic fields and temperature shifts in the ocean. 
  4. Some sharks are pregnant for two years - The spiny dogfish shark can take two years to gestate before delivery, making it the longest gestation period of any vertebrate. And you thought nine months was a long pregnancy!!
  5. Shark skin feels like sandpaper - Shark skin is made up of tiny teeth-like structures called placoid scales, or dermal denticles. These scales point towards the tail and help reduce friction from surrounding water when the shark swims.
  6. Sharks can go into a trance - When you flip a shark upside down it can go into a trance-like state called tonic immobility. 
  7. Blue sharks are really blue - The blue shark displays a brilliant blue color on the upper portion of its body and is normally snowy white beneath. However, most sharks are brown, olive, or grayish.
  8. Some sharks have a “spiracle” - Located behind their eyes, the spiracle supplies oxygen directly to the shark's eyes and brain, when it’s immobile. Most sharks have to keep swimming to pump water over their gills.
  9. Sharks live in a huge variety of habitats - Sharks can be found from the coral reefs of the tropics, to the greatest depths of the oceans. Sharks live under the Arctic Sea ice and bull sharks have even been found in freshwater rivers.
  10. Most sharks are cold-blooded - Their body temperature is much like the temperature of the water they swim in. But great white sharks are partially warm-blooded, allowing them to move faster when hunting prey.  

Why are sharks endangered?

There are over 500 species of shark, 143 of these are under threat, listed by IUCN from vulnerable to critically endangered. Major threats include:
  • Overfishing - Some 100 million sharks are killed by humans each year. Sharks are caught for their fins (which are a delicacy in Asia) whilst others end up in your fish & chips. 
  • By-catch - Many sharks are accidentally caught in fishing gear.
  • Destruction of natural habitat - Shark’s homes have been severely impacted by climate change. 50% of the world’s coral reefs have been lost, and the rest could disappear completely by 2050 if climate change remains unchecked.  
  • Plastic pollution - Filter feeder sharks often ingest plastic, leading to ingestion issues and death. Also, sharks frequently become entangled in plastic waste.  

How can you help?

  • Purchase sustainable seafood - Pledge to buy seafood that's certified as being sustainable and urge stores and restaurants to carry certified fish.
  • Stop the illegal trade in shark products - Don’t eat shark fin soup. Boycott restaurants and hotels that have it on their menus. 
  • Reduce your plastic consumption - Use less plastic and recycleall your plastic waste.
  • Raise awareness about the effect of plastic pollution - Share the underwater impacts of pollution through data collection and reporting to influence policy.
  • Start a fundraiser - Do you know who makes the greatest impact for ocean protection? You do! When you become a fundraiser, you take the future of our ocean into your own hands.
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