The salmon is more than a fish- it is a symbol of the bounty of nature and of the quality of the environment. Its continued survival depends on two factors: first that the fishermen control their catches so that there will always be enough salmon to provide for the next generation. Secondly, our rivers and lakes must be kept free from pollution. The existence of the salmon is a clear indication that conservation are winning the struggle for a healthy environment.
Eight thousand years ago the Mesolithic people, the first settlers in Ireland, made their dwellings on the banks of the Bann where they could easily catch salmon. Ever since, this species has held a position in the centre of the stage of Ireland's fishing industry.
Apart altogether from the supreme food value of the salmon its importance comes from its unusual life cycle. It is an "anadromes" fish: one which breeds in freshwater but goes on sea to find the greater part of its food and to grow big enough to return to freshwater to breed. This means that it must travel through rivers in which it may be caught much more easily then any other large species of fish. This way of life also subjects the salmon to far more risks than are faced by other species of fish.
In midwinter the adults form pairs in small streams where the water is clear and flows over a gravel bed. The female excavates a pit in the bed of the stream and deposits thousands of eggs, known as "spawn": a five-pound female lays about 2,500 ; a ten-pounder twice as many. The male fertilises the eggs as they are laid and then the female covers them up with gravel, forming a heap of stones on top of them. This nest is known as a "redd" and in the safe cover provided by the stones,the eggs begin to develop. Early in March, about two months after the eggs were laid, the young salmon on an aggressive life in the open stream.
From the very first, the salmon is a territorial fish: each individual striving to find a favourite patch on the stream bed and driving its companions away to a safe distance. In the course of the next two years, the young salmon grows, moving downstream to deeper waters and occupying more and more living space. In the month of April, at the beginning of its third year of life, it is called a "smolt" and swims downstream to make its way to the ocean. There it will stay for more then a year, feeding on smaller fishes and growing at a much faster rate than was possible in freshwater. It took two years to attain a weight of 50 grams but the next year sees an increase to 2,500 grams.
Early in the summer of the year following its descent to the ocean the salmon, called a "grilse" , stops growing and begins a return journey which will bring it to the stream in which it was born. Back in the river it eats no food, although it will now and again snap at a passing insect or fish from force of habit. It swims gradually upstream and after a fasting period of several months mates and spawns. Exhausted by the long fast and efforts of spawning, the majority of salmon will not survive to spawn again.
Spring Salmon
Although the majority of fish salmon spend fourteen or fifteen months at sea, returning to the coast in summer proportion stay away longer and come back any time between Christmas and the month of may. They are much bigger than the grilse and are known as 'Spring fish". The earliest off these to arrive in freshwater will have to fast for a year before before spawning time comes. These, above all, are the fish which were a vital source of food for our ancestors. The point is that they could be caught in the early months of the year when most other kinds of food were unobtainable. So it may be said that the early existence of the people of Ireland was made possible only by the presence of the salmon.
Salmon Fishing - Legal and Illegal
As soon as the salmon approach the coast on their journey home from the ocean, they come under threat from fishermen. In the open sea they are caught in 'drift nets', long curtains of netting hanging form the surface in which the migrating salmon become enmeshed. In the estuaries fishermen surround them with 'draft nets' which are hauled in to the shore. Near the mouths of some of the best rivers salmon traps, fixed cages which the salmon swim into have been used for centuries. Finally there are the sport fishermen with rod and line. These are just the legitimate methods. There are also endless ways of netting, spearing and poisoning which are well known to many illicit fisher folk.
Threats to the Salmon.
Then there are the man-made hazards which can prevent the salmon from reaching their spawning grounds or which can kill the young fish. Dams made for electricity or for water supply effectively block the passage of the fish trying to reach their spawning streams. Pollution of rivers at its worst kills all the fish, but at a lower level can make life almost impossible for them by killing the food organisms or covering the gravel where the eggs should be laid. Major drainage operations in many cases cover the gravel of the stream bed with silt, making the habitat unsuitable for young salmon.
Finally there is the important factor of the struggle for existence between the salmon themselves. Each young salmon must have a minimum area of stream bed for its exclusive use if it is to grow to be a smolt. This means that there is an upper limit to the number of smolts which can develop in the rivers of Ireland.
Of all these factors, only two could bring about the total destruction of our salmon stocks. The first is the damming of rivers. Laws which make sure that fish passes are built wherever they are needed have overcome this problem so far. The second and more serious problem is pollution. Again, there are good laws to cover the problems but in this case enforcement of the law is much more difficult. To date, no lasting damage has been done to fish stocks but the threat will never go away.
The key factor in maintaining our salmon fisheries is control of the ways of fishing. The law restricts the numbers of nets which may be used in our coastal waters and completely forbids netting in fresh water. The nets must be kept below certain dimensions and no netting at all is allowed at weekends. No salmon fishing is allowed between 13th October and the end of December. This nationwide 'close season' is enforced so that the salmon are left in peace all through the spawning season. The 'open season' begins in some rivers on New Year's Day but in others not until later in the year.
If fishermen would obey the regulations and if pollution and interference with rivers could be controlled, then the future of the salmon would be assured. At present the laws are adequate for the protection of the stocks. The most intractable problem is a psychological one: many fishermen do not yet accept the fact that the laws have been drafted above all things to protect their livelihood.
Development
There is a positive side to management, concerned with increasing the numbers of salmon rather than with simply maintaining the natural stocks. This is based mainly on operating salmon rearing stations in which the young fish are fed artificially and then released to grow in the sea. This development side of the fishery is controlled by the Central Fisheries Board.
At the base of all effective management of the stocks lies scientific knowledge. Scientists working for the Department of the Marine are carrying out many studies on the stocks of Irish salmon. One of the most important developments in recent years had been a system for injecting microscopic metal tags into the young fish. Recapture of adult salmon carrying these tags gives vital information on how successful the various methods for rearing and releasing the young have been. Ultimately, the scientific information shows how the existing regulations may be improved so that more salmon will be available for the fishermen.
For more than a century salmon culture in Ireland had been confined to the freshwater part of the life cycle. The 1970's saw the introduction of the system of transferring smolts to cages in the sea and feeding the salmon until they had grown to market size. In the course of the 1980's cage rearing developed into a substantial industry, employing more than one thousand workers.
Salmon farming has had a major impact on small rural communities by providing new jobs and also on the welfare of wild salmon by reducing the profitability of illegal fishing. It has also met with controversy since the food and medicaments used may be seen as pollutants. Because of these risks, salmon farming is stringently controlled by licensing. The fact is that salmon, above all fish, require a clean and healthy environment. Therefore any deterioration will affect the salmon farms themselves before it causes damage elsewhere. This, more than any system of regulations, will ensure that the cage farming industry will develop without any serious adverse impact.
