The South Western Regional Fisheries Board has written to the Broadcasting Complaints Commission claiming that an RTÉ Prime Time programme on commercial salmon fishing was "biased and grossly inaccurate".
The programme broadcast on February 8th claimed there was poaching in Kerry.
Footage showed two men in boats in daylight setting illegal fixed nets to poach salmon in Castlemaine harbour.
The men had their faces blanked out.
The board wants the release of the film clip used in the Prime Time programme, which RTÉ said it no longer had.
The fisheries board has told the commission that the one-minute footage of alleged salmon poaching in the harbour was "in all probability false".
The board said it conducted "an extensive investigation" into the allegations made on the Prime Time broadcast.
Following the programme the fishermen in the film contacted the draft net fishermen's association in the harbour and the board to say they were in fact fishing for ray and were doing so legally.
Aidan Barry, chief executive of the South Western Regional Fisheries Board, told a board meeting this week that RTÉ had refused to hand over the full footage, and had in correspondence said it did not film the piece itself.
The Prime Time programme had damaged the board's credibility as the body charged with the protection and conservation of fisheries in the area.
In a letter to the board, Colm Magee, executive producer of Prime Time, said they had been offered the material during preparation for the programme and had checked its bona fides.
After the programme they had returned the material to the owner, the letter said.
The film was obtained "for transmission only" and not for the purposes of any other organisation, said Mr Magee.
In a statement issued yesterday, RTÉ said Prime Time wholeheartedly stood over its report on the decline of salmon stocks in Irish waters and what experts believed to be the primary cause of their decline.
"The claims made in the report were presented in a fair manner, with both those opposed to drift net fishing and those supporting it afforded the opportunity to put their cases and respond to points made to them."
It added: "RTÉ believes that a one-minute film section of the report did in fact illustrate poaching and that the bona fides and provenance of the material had been thoroughly verified before transmission."