Aquaculture for all

Oil rigs could become coral farms

Australia - Decommissioned oil rigs off Australia's coastline could become hubs for marine-based businesses such as coral harvesting for aquariums, a fish expert says.

We may soon be harvesting coral for equariums that has been grown on the remains of old oil rigs, say researchers
(Image: iStockphoto)
Professor David Booth, of the Sydney Institute of Marine Science and University of Technology, Sydney, says there are up to 60 oil rigs in Australian waters that are due to be decommissioned in the next decade. Most are in the Bass Strait between Tasmania and mainland Australia.

Last year Booth was involved in Federal Department of Industry, Tourism and Resources (DITR) talks on the decommissioning of oil rigs. The future of Australia's ageing oil rigs is due to be on the agenda again with the DITR to release a discussion paper in the next two months.

Booth says the options for decommissioning oil rigs include: leaving them intact and in place; towing them away for dismantling; removing the platform and using explosives to topple the remaining shell; and removing the platform and leaving the remaining shell in place. In the last two cases, the shell of the oil rig forms an artificial reef. Booth says in some cases keeping part of the rig in place could benefit the marine environment.

Case-by-case approach
"There is no easy answer ... you can't just say take them all away," he says.

For example, the removal and towing of the rig to Singapore or India for dismantling could have a negative impact on the environment due to the carbon cost of towing the rig and the risk of oil spills. "If you did all the sums it might not be an environmentally friendly thing to do," he says.

The marine ecologist says one of the programs he highlighted in last year's government talks was the "rigs to reefs" project in the southern US state of Louisiana. He says there are about 3000 oil rigs in shallow waters off Louisiana's Gulf of Mexico coastline. Under the program, some decommissioned oil rigs have been used for marine-based industries including fish and oyster farming, dive tourism and growing coral for aquariums.

"It has brought amazing economic benefits to the place," he says.

Study
Booth is part of the SEA SERPENT project, jointly funded by the federal government and oil companies, which allows scientists to use oil rigs and their facilities to study marine life.

SEA SERPENT coordinator Dr Adele Pile of the University of Sydney, says one of the project's missions is to examine the impact of oil rigs and drilling on underwater biodiversity.

"Around the world this is an understudied issue," says the deep sea ecologist, adding that more information is needed before decommissioning rigs.

"We have to understand how they've changed the ecosystem. Just because we've changed something it doesn't necessarily mean it is wrong. It could be oil rigs improve biodiversity and become oases for organisms that would otherwise be rare or endangered."

Pile says the team will be analysing whether the artificial reefs formed around rigs are sustainable. "If it is sustainable then maybe we are better off leaving them in place, but we won't know until we ask the question."

Source: ABC Science Online
Create an account now to keep reading

It'll only take a second and we'll take you right back to what you were reading. The best part? It's free.

Already have an account? Sign in here