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River Shark Facts

River Shark

River Shark Facts (View larger version)

  • Up to 73 million sharks are killed every year in support of the global shark fin industry.

  • 926,645 square miles (2.4 million square kilometers) of the ocean is off limits to shark fishing.

  • Losing sharks could have consequences that affect the entire ocean ecosystem.

  • Bull Sharks are the only shark species that frequent freshwater, and can remain for long periods of time.

  • Osmoregulation is the process that allows sharks to cellularly adapt their body fluids to cope with their environment.

  • Bull Sharks can tolerate hypersaline water as high as 53 parts per thousand.

  • 90% of a shark’s body secretion into the water is done by the gills, in order to balance internal pH.

  • The spiral valve intestine in sharks increases the surface area of digestion and conserves space within the body.

  • Some sharks will consume other sharks for food.

  • 80% of the 350 shark species grow to less than 5 feet are unable to hurt people and rarely encounter them.

  • Adult bull sharks are not known to have any natural predators, except humans.

  • The largest bull shark caught on rod and reel weighed 771 lb. 9 oz.

  • Humans are more at risk to die from a dog attack then a shark attack.

  • Bull Sharks get their name from having a blunt, round snout, and robust-body, which is used to head-butt their prey before biting.

  • Bull sharks can live up to 16 years.

joanne walker
joanne walker

correct me if I am wrong most shark attacks in fresh salt  water are done by bull sharks?