The Great Barrier Reef is an incredibly valuable resource, providing habitat for all sorts of marine life and a source of recreation and tourism for scuba divers, snorkelers and reef walkers. Coral reefs constitute an entire ecosystem to themselves, serving as protection for young fish and a food source for all their denizens. It’s important to realize, though, that reefs are a finite resource; without proper management and protection, we’re likely to find out just how finite and fragile reefs really are.
Researchers have discovered that over the last 27 years, the coral cover of the Great Barrier Reef has dropped by more than half. At the present rate, the coral cover could be down by half again inside of a decade. There are a few reasons behind this startling decline; increased storms, bleaching, and a population explosion of a predatory starfish that depletes the nutrients in the coral. The trend has accelerated since 1998, with two-thirds of the present coral loss happening since then.
Tropical cyclones have been accountable for about half of the loss of coral reef structure, with the reef being hit by six major cyclones in just the last seven years. Cyclone Hamish ran for over 900 miles, leaving a wake of devastation much worse than most cyclones; it also ran parallel to the Australian coast, when most cyclones cross the reef at an angle. The crown-of-thorns starfish (cots) has also been a huge contributor to the degraded condition of the reef. First documented in 1962, the Cots population has shot to a level where they eat 90% of the reef’s coral in infested areas. Evidence suggests that the Cots outbreaks start after major floods in rivers that flow into the sea. Overfishing and collecting of coral for aquariums and other marine-biology projects have also contributed to the reef’s problems.
To help restore the health of the Great Barrier Reef, scientists point to taking on the crown-of-thorns starfish, managing fishing operations, and working globally to cut carbon dioxide emissions and global warming. It’s believed that global warming may be one of the biggest culprits, contributing to the severe storms and acidification of ocean water that have been so detrimental to the reef’s structure and ecosystem. As fragile as the coral reefs are, they can also be resilient and regenerate themselves – given the proper measures and care.