How is the Great Barrier Reef under threat?

• The different threats to the Great Barrier Reef:

  • Unsustainable fishing
  • Aquarium trade
  • Coastal Development
  • Climate change (causes Coral Bleaching)
  • Tourism
  • Crown of Thorns Starfish
• What is Commercial fishing?

  Where fish are caught in large amounts and sold for profit.
• Unsustainable fishing:

  Commercial fishing uses large nets that can accidentally catch animals like dolphins, whales, dugongs, sawfish, sea snakes, turtles, and sharks.
• Unsustainable fishing:

  Companies make money by taking tourists on fishing trips, but some do this illegally, leading tourists to catch and kill large predators in the reef.
• How does unsustainable fishing threaten the reef?

  Both types of fishing can harm the food chain and reduce biodiversity.
• Aquarium trade:

  Fish and coral are taken from their habitat to be sold in the aquarium trade.
• Aquarium trade:

  Some people in the trade argue that only sustainable amounts of fish and coral are taken.
• How does aquarium trade threaten the reef?

  Many species are declining because of this, which could lead to extinction.
• What is Coastal development?

  Coral development is any growth or change within the Great Barrier Reef catchment.
• Coastal development:

  This development makes water flow too fast, not giving it time to clean before reaching the reef.
• Coastal development:

  Development in these areas can also cause noise pollution.
• How does coastal development threaten the reef?

  It damages the reef, which needs specific fresh water and nutrients, and disrupts wildlife.
• What is Coral bleaching?

  Corals get stressed when conditions change, like:

  • Sea temperatures rising (for example, because of climate change). Even a small increase of 1-2°C can cause bleaching.
  • More acid in the water, also caused by climate change (this is called ocean acidification).
  • Pollution.
• Climate change (causes Coral bleaching)

  The stress makes the coral polyps expel the algae in their tissues, which causes them to turn completely white.
• How does climate change threaten the reef?

  Bleaching can kill coral reefs and take away homes for other animals. Fish disappear, and animals can't hide anymore.
• Tourism

  Divers take pieces of coral home, which harms it. Boat propellers and anchors can also damage the coral.
• How does tourism threaten the reef?

  This destroys the reef and disrupts the animals living there.
• Crown of Thorns Starfish

  This type of starfish eats coral and grows in number when the water is very polluted.
• How does Crown of Thorns Starfish threaten the reef?

  Some reefs have been completely destroyed by these animals.