threats to the great barrier reef
27% of the world's reef are lost by 2000! Half of the coral in the Great Barrier Reef is dead!
coral bleaching
Coral can only stand a certain temperature. If it is too warm it Bleaches.
crown Of THORNS starfish (acanthaster planci)
The Crown Of Thorns Star Fish is a massive threat to The Great Barrier Reef. It is named this because of its spines. The problem with this star fish is that is eats the Coral! Thats right is eats the Coral! Their spines are actually venomous. In just a single year a single Starfish can destroy 13m of reef and in just a single night it can eat its length of coral. On average a female will lay 60 million eggs but it can be up to 250 million eggs! When they are three years old they will start eating coral. Adult males can grow to 1m across. Unlike most starfishes that have five arms this one can have 14-20! Two of the Starfishes few predators is the Humbhead Wrasse and Triton (Charonia Tritonis). It is a type of snail. The Crown Of Thorns Starfish threatens many reefs. It eats the coral by letting its stomach go through its mouth then its digestive enzymes allow it to eat the coral. The terrible thing is that they eat so fast that the coral can't reproduce. The only threats to the Great Barrier Reef that are worse than this starfish is Bleaching and Cyclones.
dredging
Dredging is a massive threat to the crystal clear waters of the Great Barrier Reef. Over 52 million tons of seabed have alredy been dumped! Isn't that horrible. Seabed and rock is dug up and dumped into the pristine waters of the Reef! The seabed and rock can travel for miles . This means it severely damages the water quality, seagrass and coral! Many dead Dugongs, Marine Turtles and violently sick fish and much, much more have been found. Their death would of been caused because of the dredging. More terrible dredging is planned!
fossil fuels
Fossil Fuels helps create more extreme weather like cyclones and storms which damage the Great Barrier Reef. It also causes ocean acidification. This is like having a cordial drink but with no water if it gets too strong it will kill the coral! This means it turns white and dies.
cyclones and storms
You can see in the picture the damage done to the Great Barrier Reef by Cyclone Yasi. They strip it and make it a desert!
over fishing
As well as taking a ridiculous amount of marine life it also damages the coral and the bottom of the reef.
POLLUTION
Chemicals from farms is having a major impact on the Great Barrier Reef. This causes pollution and makes the water quality poor. This is good for the Crown Of Thorns Starfish babies and helps them be healthy.
image credits
http://www.scienceinpublic.com.au/marine/mediarelease
http://www.abbotpointactiongroup.org/dredging-impacts.html
http://blogs.toorakcollege.vic.edu.au/katec1/2012/09/22/cyclone-yasi/
http://gbrthreats.blogspot.com.au/2010_03_01_archive.html
http://www.abbotpointactiongroup.org/dredging-impacts.html
http://blogs.toorakcollege.vic.edu.au/katec1/2012/09/22/cyclone-yasi/
http://gbrthreats.blogspot.com.au/2010_03_01_archive.html