Cyclone Yasi impacts on the Great Barrier Reef assessed

Published: 20/07/2011

Great Barrier Reef Marine Park Authority (GBRMPA) and Queensland Parks and Wildlife Service marine specialists have returned from their initial surveys to assess the damage caused to the Great Barrier Reef by cyclone Yasi.

About 13 per cent of the Great Barrier Reef, from Cairns to Townsville, was exposed to Yasi's destructive winds. The scientists conducted rapid assessments of 36 reefs in this region to ascertain the extent of the damage.

The affected area represents a 300km stretch of the 2400km-long Reef, with serious damage in patches and minor or nil damage in other parts. An initial statement of findings will be released by GBRMPA shortly, with more detailed scientific assessments to be released in the coming months.

"The good news is that the damage to these reefs has been patchy," GBRMPA's assessment coordinator Dr Paul Marshall said. "In some instances, neighbouring reefs and coral structures have remained relatively unharmed.These surviving corals will help the damaged areas to rebuild.

"The areas that faced wind gusts of up to 285 km per hour were the most seriously damaged. Coral has been broken, and torn from the reef and tossed around.

"Branching corals have suffered the most, with the remnants being strewn across the seabed floor, while large plate corals have been snapped off and dumped into deeper water. Some corals that are hundreds of years old have been tipped on their sides."

The GBRMPA will be monitoring the recovery of these reefs closely as well as undertaking further research into the impact of the recent cyclones and floods on the Reef and the industries and communities that rely on it.

"Research conducted by James Cook University into the effects of cyclone Hamish, which tracked along the Queensland coast in 2009, shows that coral trout can go off the bite following a cyclone," Dr Marshall said. "We have received similar reports from fishers between Innisfail and Bowen after cyclone Yasi.

"However, the research also reported increased catch rates of red throat emperor. Other species that are expected to thrive due to improved breeding conditions include barramundi and mackerel.

"A couple of tourism operations in the path of the cyclone, particularly on Dunk and Bedarra Islands, have suffered quite severe damage to their facilities and we will be talking to those operators about their plans to recommence operations.

"However, cyclone Yasi tracked between the main tourism sites in Cairns, Port Douglas and the Whitsundays and we were very pleased to find that those areas are still healthy and thriving with marine life.

"For the time being, it is important to remember while parts of the Reef in the path of the cyclone have been damaged, most of the Great Barrier Reef remains unaffected."

The Great Barrier Reef Outlook Report 2009 identified climate change, and its associated impacts, including increased frequency of severe cyclones, as one of the Reef's greatest challenges.

"In light of this, the GBRMPA is working with its partners to build the resilience of the Great Barrier Reef ecosystem to aid the recovery of the Reef from climate-related events," Dr Marshall said.


Name: GBRMPA Media
Contact: (07) 4750 0846