Fisheries Officers began investigating at first light on Monday and estimated 2000 to 3000 salmon were found strewn along Tathra Beach and Nelsons Beach.

A spokesman said all of the fish were in an advanced state of decomposition, indicating that they may have been dead for at least three to four days.

The fact that this fish mortality is restricted to one species indicates that there is nothing wrong with the water.

It appears that this fish mortality is related to a specific isolated event.

A commercial fishing vessel targeting salmon was active near Tathra during the week preceding this fish kill.

The fishers however report no abnormal occurrences during their fishing operation that may have resulted in fish being washed up on the beach.

There is currently no evidence to link the commercial fishers with the fish kill.

Tests on the fish unlikely to provide a cause of death, due to the stage of decomposition of the fish.

Salmon are a very abundant, successful species and there is no concern about the health of the East Coast stock.

Esma Hodges of Dalmeny called in to the ABC radio as news broke about a similar event on Brou beach probably around 16 years ago when she was walking the dog.

She saw dead salmon all the way up the beach with their stomachs broken open and she thought it may have been dolphins, but the event in Tathra sounds much more extensive.

Investigations into the fish kill are continuing and anyone with information can call the Eden Fisheries office at 6496 1377.