Jun 24, 2008

What happens to reef life when fishing is banned?

Here's a montage of extracts of various reports.
Full reports on the wildsingapore news blog.

A controversial decision to halt commercial and recreational fishing across vast areas of the Great Barrier Reef has proven remarkably effective for reviving numbers of coral trout.

On 1 July 2004 the Australian Government threw a protective net over the Great Barrier Reef by banning fishing in about a third of the marine park.

The move, which locked fishermen out of 100,000 square kilometres of the reef, created intense community debate, with the Government offering compensation packages to those affected by the ban.

This sweeping approach to conservation was the first of its kind--such a large-scale ban on fishing was unprecedented.

Surveys following the ban show that numbers of coral trout "have increased by over 60% in no-take areas around two groups of inshore islands – Palm Island and the Whitsundays – 18 months to two years after rezoning. By contrast, coral trout numbers in nearby fished areas did not change.".

A second team found that coral trout numbers had increased in no-take zones around reefs from 32 to 200 kilometres off-shore. "In four of these offshore regions, numbers of coral trout were between 31 and 64% higher compared to unprotected regions nearby, just two years after the zoning took place."

The two teams are monitoring 160 different species of fish, but so far only numbers of coral trout have changed since the rezoning.

Comments by scientists include:

"It's a very positive start, but full recovery of coral trout will take 10 to 15 years of really effective protection"

"Our results provide an encouraging message that bold political steps to protect biodiversity can produce rapid, positive results for exploited species at ecosystem scales"

"The study is encouraging, but no-take areas are only part of the solution. The risk is that this may not be adequate, in the long run, to sustain the ecosystem as a whole. Pollution, climate change, and water quality can also drive down fish numbers".

What is coral trout?
Coral trout is a term used for various kinds of groupers, among the favourite seafood in our part of the world.

from the CRC Reef Research Centre website

The term coral trout actually describes a number of different species belonging to Family Serranidae (Groupers) including:

  • Common coral trout or Leopard trout: Plectropomus leopardus
  • Blue-spot trout: Plectropomus laevis
  • Footballer trout: Plectropomus laevis (a different colour morph of blue spot trout)
  • Bar-cheeked trout or Island trout: Plectropomus maculatus
  • Passionfruit trout or Leopard trout: Plectropomus areolatus
Coral trout are the favourite target fish for all sectors of the fishery because they are a good eating fish and command high market prices locally and overseas. The total commercial catch of coral trout was reported at over 1500 tonnes in 1998.

1 comment:

Jeffrey said...

The only controversy here is the political will to implement the ban .. it has been "proven" that having no-take zones will increase fish stocks in the surrounding waters due to spill over effects from the fish within the protected area. The model in this type of management is Apo Island in the Philippines, where such a system has been in place since the 1990s.