Threats to the Reef

The Great Barrier Reef is a vast interlinking web of life. All the plants and animals on the Reef play a part in keeping this web healthy and strong, and the relationships between different organisms on the Reef have been built and maintained over many thousands of years. Humans are relative newcomers to the Reef, and we've brought some big changes. Many things that we do on the Reef and on land have the potential to threaten the Reef's fragile ecosystem.

On the Great Barrier Reef, careful management has made sure that most of our activities don't threaten the long-term health of the ecosystem.

Research has shown that tourism doesn't exert much pressure on the Great Barrier Reef because it is thinly spread over such a vast area. In addition, tourism operators have a vested interest in the health of the Reef, and act as watchdogs, alerting management authorities early if they see something going wrong.

Fishing on the Reef is carefully managed by the Great Barrier Reef Marine Park Authority and Queensland Department of Primary Industries, to ensure that it will be sustainable for many generations to come.

Ironically, the biggest threats to the Reef come from human activities on land.

Water quality and run-off

Sediments and nutrients, fertilisers, pesticides, toxic chemicals, sewage, rubbish, detergents, heavy metals and oil run into rivers and out to the Great Barrier Reef lagoon, where they can threaten plants and animals on the Reef. Land users and governments are now working together to improve the quality of water flowing onto the Great Barrier Reef as part of the Reef Water Quality Protection Plan.

Climate change

The Earth is getting warmer, and is now higher than it has been for 2000 years. A large body of research suggests that this is due to greenhouse gases being released into the atmosphere by human activities such as burning fossil fuels and deforestation. Even small changes in temperature can have a devastating effect on the natural environment. Sea temperature rises of just 1 or 2 degrees centigrade can cause coral bleaching and death on a worldwide scale.