Climate change will damage Australian fish stocks

Laura Anderson, Adelaide Now 6 Oct 08;

CONSUMERS will find it harder to buy salmon, king prawns and barramundi in coming years with a report showing climate change is threatening the nation's fish stocks.

Rising temperatures, ocean currents, rainfall and extreme weather will have negative impacts on the $2.1 billion fish industry and will also upset marine ecosystems, the Federal Government report to be released today warns.

Compiled by the Department of Climate Change, the report says the Tasmanian salmon, rock lobster and abalone industries, and barramundi, prawns and mudcrab fisheries in the north of Australia are most at risk.

The report did not specify any impact on South Australia's major fisheries, which has an export value of about $519 million.

Major industries include southern bluefin tuna and Spencer Gulf prawns out of Port Lincoln and southern rock lobster out of Eyre Peninsula and the South-East.

It says coral reefs will also be affected, with coral bleaching likely to have flow-on effects for species such as the coral trout and red emperor.

Climate Change Minister Penny Wong said the report found climate change "is likely to affect not only the fishing industry itself, but also the regional and coastal communities the industry supports".

In relation to aquaculture production, South Australia's most profitable species are tuna and oysters.

The report says climate change is expected to have "direct and indirect impacts on all Australian aquaculture production environments". Meanwhile, the South Australian Government has warned that climate change is posing a "considerable" threat to the state's coastal homes.

The State Government has sounded the warning to a federal parliamentary committee, which will head to Adelaide on Wednesday to investigate the impact of climate change on coastal communities.

The State Government has called for a review of existing coastal communities to determine those most at risk, and a high-resolution digital elevation model of the coast, to evaluate the potential impacts of climate change.

Fish stock at risk in climate change
Mark Metherell, Sydney Morning Herald 6 Oct 08;

CLIMATE change is likely to hit supplies of many of Australia's favourite eating fish, including barramundi, salmon, rock lobster and prawns, the most extensive study on the subject yet undertaken by the Federal Government has warned.

The CSIRO study, commissioned by the Department of Climate Change and to be released today, reports the overall impact of global change "will pose some very significant risks to the sustainability of fisheries and aquaculture in Australia".

Projected changes in temperature, ocean currents, rainfall and extreme weather events due to climate change are all likely to significantly influence fish stocks and marine ecosystems in the $2.1 billion Australia fishery and aquaculture industry, the report finds.

It predicts that in the cooler southern waters, adverse impacts will hit the $220 million-plus Tasmanian salmon industry, which represents a third of the country's aquaculture production.

The spread of the long-spined sea urchin south along the east coast of Tasmania, holds "serious implications" for the Tasmanian rock lobster and abalone fisheries, which are together worth more than $150 million.

"Considerable impacts" would also hit the northern prawn fisheries. Impacts on coral reefs, such as an increased incidence of coral bleaching, would have flow-on effects for fisheries based on reef-associated species, such as coral trout and red emperor.

Changes in rainfall patterns would endanger catches of prawns, barramundi and mud crabs in the northern fisheries.

The Climate Change Minister, Penny Wong, said the report, a preliminary assessment of the challenges posed by climate change, found it was likely to affect the fishing industry, as well as the regional and coastal communities the industry supports.

Climate change impacts would vary by region, and some data suggests that effects may have already occurred.

Senator Wong said the report was another reminder of the need to tackle climate change through reducing carbon pollution.

The Rudd Government is working on the final design of its Carbon Pollution Reduction Scheme, to be released in a white paper by the end of the year.

The study says there is "little consolidated knowledge of the potential impact of climate change".

Fisheries in south-eastern Australia were most likely to be affected by changes in water temperature, northern fisheries by changes in rainfall and fisheries in Western Australia by changes in the Leeuwin Current.

Global warming set to shake our eating habits
Paul Maley, The Australian 6 Oct 08;

CLIMATE change is likely to deprive us of the pleasures of eating beef and lamb, instead forcing us to contemplate platefuls of kangaroo meat and threatening another Australian table staple -- seafood.

A report to be released by the CSIRO today says changes in temperature, ocean currents, rainfall and extreme weather events could cost Australian fisheries tens of million of dollars.

Hardest hit could be stocks of Tasmanian salmon, estimated to be worth $221million in 2005-06 and representing 30 per cent of the total national aquaculture production.

The report says projected ocean warming of 2-3 degrees by 2070 could render salmon farming unviable, leaving open the possibility of salmon farmers having to shift their operations offshore to deeper, cooler waters.

And the retreat of mangrove forests and seagrass beds could leave commercially farmed banana prawns, mud crabs and barramundi without their habitats, the study found.

Climate Change Minister Penny Wong said the report was a preliminary assessment of the effect climate change could have on Australia's commercial fishing and aquaculture industry, worth about $2.1 billion.

"The report finds climate change is likely to affect not only the fishing industry but also the regional and coastal communities the industry supports," Senator Wong said.

"It finds climate change impacts will vary by region and that many impacts are expected to be negative, with some data suggesting that effects may have already occurred."

The CSIRO assessment comes on the back of a similar warning issued by the Rudd Government's climate adviser, Ross Garnaut, who warned that sheep and cattle farming was "highly vulnerable" to climate change.

Professor Garnaut backed kangaroo meat as an alternative, on the grounds that kangaroos emit "negligible" levels of methane gas.

"For most of Australia's human history -- around 60,000 years -- kangaroo was the main source of meat. It could again become important," the CSIRO report says.

However, the report says climate change may have positive impacts on some fish stocks.

The CSIRO's Richard Matear, who helped write the report, said some species could benefit from expanded habitats.

"There are other fisheries that will benefit from having expanded range because temperatures are warning and they can move further south," Dr Matear told The Australian.

But he said that given the long lead time with some aquaculture facilities such as salmon farms, the industry needed to start thinking about the potentially destructive effects.

"When people put these aquaculture facilities in place they're looking at investments for 10-20 years, so people need to start thinking about the potential effects now," he said.

Dr Matear said it was not certain all of the changes documented in the report were attributable to climate change.

The infestation of long-spined sea urchin that threatened Tasmanian rock lobster and abalone fisheries was not necessarily the product of climate change, he said. "Is that a climate change signal or is it more likely a human impact of fishing? I don't think it's certain."

Climate Change Threatens Australian Fisheries
Michael Perry, PlanetArk 7 Oct 08;

SYDNEY - Climate change threatens Australia's A$2.1 billion (US$1.6 billion) commercial fishing and aquaculture industry, but may create new wild fisheries as tropical marine species move south as sea temperatures rise.

Changes in sea temperatures, currents, winds, rainfall, sea levels and extreme weather events threaten to adversely affect fish and shellfish numbers, said a report by the Commonwealth Scientific & Industrial Research Organisation (CSIRO).

"It is apparent that climate change will impact the biological, economic and social aspects of many fisheries," said the CSIRO report released on Monday.

"South-east fisheries are most likely to be affected by changes in water temperature, northern fisheries by changes in precipitation, and western fisheries by changes in the Leeuwin Current (a warm southerly current), said the report.

It said many marine species "may be lost as the climate continues to warm" and alters the island nation's two main ocean currents, the East Australian Current and the Leeuwin Current, which support several commercially important species like rock lobsters, scallops, sardines, whitebait and tropical tuna.

Australia's A$220 million salmon industry off the southern island state of Tasmania could be the hardest hit as salmon are already cultivated close to their upper thermal limit.

By 2030 sea surface temperatures in the South Tasman Sea are expected to rise by 0.6 to 0.9 degrees Celsius and along the northwest coast of Australia between 0.3 and 0.6 degrees Celsius, says Australia's Bureau of Meteorology.

The CSIRO report said a changes in rainfall could reduce catches of barramundi, prawns and mud crabs in northern fisheries of Queensland and the Northern Territory. Rainfall patterns affect nutrient levels and algal blooms containing toxins

Coral bleaching as a result of higher sea temperatures could have flow-on effects for reef-associated species, such as coral trout and red emperor.

"This report is yet another reminder that climate change imposes costs on this nation -- costs not only in terms of our way of life, but in terms of the economic costs to our industries and to our communities," said Climate Change Minister Penny Wong.

"Climate change impacts will vary by region and that many impacts are expected to be negative, with some data suggesting that effects may have already occurred," Wong said.

"The report finds there may be new opportunities for some wild fisheries where tropical species shift southward."

Australia's aquaculture industries would have to adapt to climate change through selective breeding and by regulating their marine environments, said the CSIRO report.

"Australian fisheries and aquaculture management policies do not currently incorporate the effects of climate variability or climate change in setting harvest levels or developing future strategies," said the report. (US$1=A$1.32) (Editing by Sanjeev Miglani)