Save Our Seatrout is a campaign to restore healthy runs of sea trout to Irish rivers and lakes. Stocks of sea trout have been severely depleted, especially along the western seaboard of Ireland, by parasites emanating from sea-based salmon farms.

An explosion in the population of sea lice (lepeophtherius Salmonis), a natural parasite of salmon and trout, has turned the waters close to salmon farms into killing fields for sea trout when they migrate down from freshwater in the spring.

The lice attach themselves to the trout and eat away their protective coating or eat into their flesh, forcing the traumatised fish back prematurely into fresh water, where the lice cannot survive but where there is insufficient food to sustain the trout.

The sea trout is a biologically complex version of the brown trout that breeds in fresh water but, like the salmon, migrates down to sea to feed. Unless it can feed, it cannot mature and reproduce. Unlike the ocean-going salmon, it mainly feeds in or close to the estuary of its natal river.

Since 1988, hundreds of thousands of Irish sea trout have died through lice-induced starvation, osmoregulatory malfunction or secondary infection.

Salmon farming in Ireland

The marine salmon farming industry took off in Ireland in the mid-1980s and has been the subject of great controversy ever since. By holding millions of salmon captive in open cages, year-round and in warm inshore waters, the farms have unwittingly caused an epizootic or explosion of lice, increasing the parasite numbers by several orders of magnitude.

Since the farms are almost invariably located in sheltered western bays, which are also the estuaries of Ireland’s top sea trout river systems, the greatest ecological disaster of the past 150 years has occurred in otherwise pristine parts of Connemara, Mayo, Donegal and Kerry.

There are now over twenty major salmon farms in Ireland producing a total of over 15,000 tonnes of salmon each year. Almost all of these farms are located in or close to the estuary of a major sea trout river. And, ominously, the Irish salmon farming industry wants to double in size over the next few years.

The impact on wild salmon

There is now growing evidence from Norway, Scotland and Canada that the lice from farms are also affecting wild salmon populations, as well as sea trout.

Although migrating salmon smolts do not linger as long in the estuarine danger zone as sea trout smolts and adults, they can still pick up mortal levels of sea lice larvae at the start of their ocean journey. And, as the lice grow on the fish over subsequent weeks, fatal damage is inflicted out at sea and out of sight.

In Ireland this has almost certainly been the case in many locations when there have been very warm, dry springs that allow lice to proliferate. Serious and localised salmon run failures have undoubtedly occurred following such years in parts of Connemara and Kerry.

Why does it matter?

Quite apart from their ecological importance and their fascinating contribution to bio-diversity, the sea trout (and, to a lesser extent, the wild salmon) of western Ireland have sustained a world famous sport fishery for centuries. This industry is now in a state of near total collapse, with significant impacts on employment, tourist numbers and the quality of life of many local people.

The strikingly beautiful but otherwise underprivileged western edge of Europe had few natural advantages other than its lack of pollution and its hitherto bountiful fish stocks. The loss of the sea trout represents a catastrophic blow to the region.

What can be done?

Attempts by the farms to control their lice levels - and thus to prevent the release of juvenile lice larvae into nearby waters – have centred on the use of toxic chemicals. Unfortunately, these have proved ineffective. Mistakes in the timing of “treatments” are almost impossible to avoid, the chemicals are very costly (at a time when the farms’ profits are low) and, anyway, the fast-breeding lice rapidly develop immunity to the chemicals.

Government policing of the salmon farming industry has been almost completely spineless. While there has been extensive collection of lice data from the farms over the last ten years, there has yet to be a single instance where the State has used any of the wide array of powers given to it by recent legislation to punish offending farms. Not one farm has been fined, relocated or shut down.

Were the farms to move onshore, where their effluents could be filtered, or well offshore, where the lice dispersion would be more disparate, the problem would be greatly diminished and possibly eliminated. But the industry rejects such options on cost grounds at a time when salmon farming is scarcely profitable and fiercely competitive across the globe. Ireland is a relatively small player in the world salmon market, dwarfed by the likes of Norway, Chile, Canada and Scotland, who have few location restrictions.

A lousy product

Save Our Seatrout believes these relocation choices are the only long-term options. Prolonged use of heavy-duty chemicals in the open sea clearly offers no sustainable future and will inevitably have broader negative environmental and consumer health implications.

The industry could anyway self-destruct as an increasingly sophisticated consumer rejects a production system that is both ecologically unsound, fraught with pollution and disease difficulties, propped up by copious use of antibiotics and the fruit of which is seen as vastly inferior to the real thing. Indeed, some food scientists believe that current levels of consumption of farmed salmon are actually seriously bad for public health.

So what is the point of preserving a handful of financially insecure jobs (the Irish salmon farms scarcely sustain even 400 full-time-equivalent jobs) at the expense of a natural resource with otherwise unlimited prospects and a proven potential for tourist revenue generation and job maintenance into the foreseeable future?

Supporters

The Save Our Seatrout campaign is supported by many hundreds of Irish Anglers and the following organisations:

The Federation of Irish Salmon & Sea Trout Anglers
The National Anglers Representative Association
Save Clew Bay
Save the Swilly
The Southwestern Anglers' Council
The Trout Anglers Federation of Ireland
The Western Gamefishing Association

These organisations in turn represent many thousands of anglers, tourism businesses and concerned Irish citizens.