There is not enough research into the effects of hydroelectric schemes on wild fish. And fishery boards faced with "a rash" of applications by private companies to harness rivers for electricity have no firm policies to look to for direction, this month's meeting of the South Western Regional Fisheries Board (SWRFB) heard in Macroom, Co Cork.
The mountainous regions are increasingly attractive for such schemes. There have been a number of applications for hydro schemes in Kerry, many of them opposed by the board.
At the moment, an application by one company, Hal Hydro Ltd, to harness the important Roughty River in south Kerry is being vigorously opposed by the SWRFB.
The 19-mile long Roughty is an important salmonid fishery, stretching from the mountains of west Cork to Kenmare Bay. Several hundred salmon are caught on the river annually. In the lower reaches there is a sea trout run. The river drains a catchment area of almost 80 square miles.
"The proposed scheme near Morley's Bridge outside Kilgarvan provides a serious threat to the sustainability of the Roughty fishery," Mr Michael McPartland, the SWRFB's senior environmental officer, has written to the planning office of Kerry Co Council.
Mr Jerry Keating, the Inland Fisheries Board representative on the board, is working on a discussion paper on hydro schemes.
He warned against these schemes developing at the same pace as fish farms, and said international research indicated they did huge damage to wild fish.
Rivers in the US had been destroyed and it was costing vast sums to try to get them back.
"There isn't enough research into the damage done by hydro schemes," Mr Keating said.
Hydro schemes can interrupt the passage of salmon, damage salmon on their way to spawning grounds and reduce flows of water significantly, disturbing salmon and trout in the spawning and nursery grounds of the upper reaches of rivers.
However, other members on the board said hydro schemes represented clean energy and a way would have to be found to accommodate the schemes without damaging fish.
"Anglers are opposed to hydro-electric schemes. There is another constituency out there as well. I have no doubt that with modern technology it must be possible to protect the natural resource," said Mr James Doyle, the IFA representative on the board.
He was joined by Mr John Harrington, the aquaculture representative, who said the board was opposing applications without having any firm policy drawn up.
Mr Harrington said mountainous regions with high drops and fast flows were attractive for small schemes. While the large schemes had by and large been negative on fisheries, the smaller schemes might not be damaging if properly planned.
"We have had very many hydro schemes. We have had problems with some, not with others," Mr Aidan Barry chief executive of the board said.
Alternative energy was not a matter for the board to promote. Their main function was to protect the fishery.
The SWFRB was now trying to come up with guidelines for both the developers and the board.