The cold waters of the Pacific ocean have been an important part of the Australian economy since its earliest days.

For centuries, Australia’s fishing industry depended on the supply of fish, as well as the abundance of fresh water, which in turn made Australia a vital trade partner to the rest of the world.

But in recent decades, the water quality in the Pacific has drastically changed, and the impact of this on the fish trade is felt worldwide.

Dr John McAllister, a researcher at the University of Tasmania’s Fisheries and Aquaculture Research Centre (FASRC), told News.co.au that Australia’s fisheries are facing a “challenge of unprecedented proportions”.

“The cold water has altered our trade in fish and we are losing our global market position,” he said.

The Pacific Ocean has a rich diversity of fish species, and many of them are threatened with extinction by climate change.

“For example, there are over 70 species of whitefish in Australia, some of which are already under threat of extinction, as are many species of carp and carp-like fish in the northern Pacific, like tuna, mackerel, salmon and sardines,” Dr McAllisters said.

Dr McAllisters research team also found that the global trade in freshwater fish, which includes trout, had plummeted by 75 per cent since the 1970s, with Australia losing about one-third of its fish exports.

Dr McNulty said that while the Pacific’s warming waters were impacting on Australia’s fishery, the impacts on Australian fish were much more pronounced.

“Our fish stocks are still recovering and growing well.

But if the ocean is warming up to a level that threatens our fishery in any way, that is going to have a big impact on fish stocks and on the species that are being traded,” he explained.

Dr McLaughlin said the trade in seafood in Australia was “one of the largest in the world”, with about 10 per cent of the country’s annual catch being exported.

“Australia is one of the countries where we export the most fish, and so it is going through a time of significant change in its fisheries,” he added.

“There are very few fish that we can sell on the market that are sustainable, and we need to work very hard to help them survive in the coming decades.”

Dr McNaughts team found that if the Pacific had warmed by just 3 degrees Celsius, its temperature would drop by 1.5 degrees Celsius.