How much do you know about The Great Barrier Reef?
For starters, can you guess its size? This travel bucket list favourite is so big that it can be seen from space!
The reef – which is the largest in the world – covers a massive area of approximately 133,000 square miles or 344,400 square kilometres! To put that in perspective, imagine an area the size of Greece, Switzerland, Belgium, Norway, Holland and Ireland ALL put together, floating off Australia’s Queensland coast!
The reef isn’t just impressive for its size, but for the innumerable species that live on it. Indo-pacific humpback dolphins, dwarf minke whales, bottlenose dolphins, pan-tropical spotted dolphins, killer whales, turtles, sea snakes, sharks, saltwater crocodiles, molluscs, seagrass – not to mention about 10% of all the world fish – all live on the reef! Among the 1,500 fish species which called the reef, home are snapper, coral trout, red bass, clownfish, and red-throat emperor fish. The living coral which supports all this life is one of the planet’s extraordinary natural wonders.
The reef’s rich biodiversity, warm clear waters and superior accessibility all come together to make it a popular tourist destination. Millions of people from all over the world are enticed by cruise, glass-bottom dinghy and yacht trips – as well as scuba diving and snorkelling opportunities – around the reef. While Australia’s thriving tourism industry creates massive employment opportunities, generates billions of dollars annually, and brings unforgettable joy to visitors, it also creates some problems.
For some years now, people have been raising concerns about excessive tourism affecting the Great Barrier Reef. Some of the issues they note are:
- Human activities linked to (or driven by) the tourism industry cause massive marine pollution: overfishing, coastal development through the digging of canals, logging, dredging and run-off from agriculture can all put the corals under stress. This can lead to coral bleaching, a process already occurring due to climate change. Just a 1 °C rise in water temperature above average can cause coral bleaching: as of 2018, 50% of the coral on the Great Barrier Reef has died.
- People can deposit dirt and debris (both organic and non-organic) into the ocean, polluting marine ecosystems and blocking the sunlight algae need for photosynthesis to survive. Some of the most harmful debris is plastic waste (e.g. plastic bags, balloons, hard hats, abandoned fishing nets) which can entangle and kill reef organisms and damage the reef.
- Tourists can accidentally touch or break off fragile corals while swimming or snorkelling over parts of the reef, putting the corals under stress. This can lead to coral bleaching or even coral death, which in turn impacts the whole biodiversity of the reef community since the disruption of one ocean system impacts all the others.
- Sunscreen – a tourist essential, particularly in Australia – is also damaging to reefs as it contains oxybenzone, a chemical that can harm marine fauna and cause coral bleaching. Did you know that about 4,000-6,000 tons of sunscreen end up in reef areas alone (double that ends up in the wider ocean!) each year, washing off from swimmers and divers? As a popular reef attracting many tourists, the Great Barrier Reef is especially vulnerable to sunscreen exposure.