Coles rejects bid to help avoid ancient fish extinction

Coles has rejected a shareholder push to abandon the sale of salmon from a remote harbour where an ancient species is at risk of extinction.

The supermarket giant is preparing for it's annual general meeting in November.

Earlier this month, more than 120 shareholders proposed a resolution in defence of the ancient Maugean skate, which has been hurt by the effects of salmon farming in Tasmania's Macquarie Harbour.

The harbour is the only place on earth where the skate exists and recent estimates have suggested there could be just 40 to 120 adults left in the wild.

Shareholders warned Coles "faces material risks through association with a likely extinction event of the Maugean skate" and that the ongoing sale of salmon from the harbour threatens the animal's existence.

But the retailer says the board will not be supporting a resolution to dump Macquarie Harbour salmon from Coles own-brand products by April.

In a notice about its AGM, published on Thursday, Coles says only a portion of its own-brand salmon comes from Macquarie Harbour.

It says it would be inappropriate to act while there is a federal government review underway into salmon farming in the harbour, and while other work is pending including a fresh look at population projections.

"Coles is monitoring these government processes closely. We will consider any recommendations and adapt to any regulatory changes as they arise as part of our regular reviews of our procurement policies," it said.

AAP was aware the notice was imminent and earlier this week asked about statements made by Coles Group chairman James Graham and CEO Leah Weckert in the organisation's 2024 sustainability report.

"We have been steadily reducing the volume of salmon we source from Macquarie Harbour, with plans to continue this transition in the coming year," they wrote.

But Coles has not answered questions including how much less salmon has been sourced from the harbour, or what its reduced target is for the year ahead.

Salmon Tasmania is an umbrella group for Tasmania's three big producers: Tassal, Huon and Petuna, which all farm salmon in Macquarie Harbour.

CEO Luke Martin says he's not aware of Coles reducing or cancelling any supply contracts affecting Salmon Tasmania's three member companies.

But he also says that's commercially sensitive information and he wouldn't expect to have that degree of oversight.

A range of factors have contributed to the precarious state of the skate, a species that dates back 60 million years.

Macquarie Harbour is naturally a low oxygen environment and for periods of time, human activities have worsened that situation.

Federal conservation advice ranks salmon farming as the main human contributor to the poor water quality but other activities including the production of hydro-electricity also have an impact.

Salmon Tasmania is currently funding a pilot program to artificially oxygenate the bottom waters of Macquarie Harbour, where the skate lives.

There are early signs of success but it's not yet at the point where it could account for big picture improvements.

If things continue to go well, the industry hopes to scale up its oxygenation replacement work to the point where it offsets what farmed salmon suck out.

Scientists who monitor the health of the harbour recently said conditions had improved thanks to naturally occurring processes that replenish dissolved oxygen.