Salmon fishing was practised in Iceland from its earliest history.  Official involvement started with the law on salmon, char, and trout fishing from 1932.  This law prohibited salmon fishing in the ocean, and since then, the salmon has been considered a fresh water fish although it spends a long part of its life in the sea.  The law also limits the fishing of running fishes to a certain season, the type of fishing gear, and the number of fishing rods.

The office of the Administrator of fresh water fisheries in 1946 immediately started the documentation and registration of information on the catch, and research has increased continuously.  The state operated the first salmon rearing facility in Kollafjordur until private enterprise started developing in the field.

Iceland boasts of about 250 rivers, and eighty of them count as salmon rivers.  As a rule the salmon does not run far upriver because of obstacles in the form of rapids and waterfalls.  The greatest distance it runs is close to 100 kilometres.

The Icelandic rivers are usually divided into three categories, depending on their origin:

Glacial rivers, which cause the greatest sedimentation the freighting of land.  They are very dependant on temperature fluctuations.  During winter their volume is smallest, but it increases gradually with the longer days, especially after spring equinox.  They peak in July and August.  Other forces of nature, i.e. subglacial eruptions, the emptying of glacial lagoons etc., are also important factors.  The temperature of the glacial water is close to 0°C at its source.  It rises considerably over long distances, especially in the lowland areas.  During winter these rivers usually freeze over.
Run off rivers are based on the precipitation, mostly in the least permeable areas, where the water runs off on the surface.  Usually the spring and autumn are their peak seasons.  Their water temperatures are usually mostly influenced by the air temperature.  During sub zero temperatures the ice developes from the bottom up and blowing snow reduces their flow considerably.
Spring fed rivers have constant volume and temperatures the whole year round.  As a rule, their temperature at the sources is 3-5°C, but sometimes rises during summer the further away it is measured.  They never freeze over at the source.

This classification usually does not apply to a whole river from its source to the estuaries.  Most rivers are a mixture of two or all above.

The country's mayor salmon rivers are located to the west of glacial river Thjorsa, to the north along the west coast, and in the north to river Laxa in Adaldalur.  In the northwest (Westfjords), the northeast, east (Eastfjords), southeast, and in the greatest part of the south are few mentionable salmon rivers.  The main reason is too cold water.

The salmon is mostly netted (three glacial rivers in Iceland) and angled.  In spite of the ban on ocean fishing, there are exceptions.

Records of salmon catch are available since 1897, and some vague information from earlier times about a few rivers.  The average yearly catch has increased tremendously:  1897-1909 = 5168; 1910-1950 = 15,000; 1970-1975 = 65,000.  This increase can be traced to more reliable records, better management, the opening of new areas of rivers with ladders, and increased release.

The knowledge about the salmon's behaviour in the North Atlantic is relatively limited, but a long experience of tagging should reveal increased information with time.  The main purpose of tagging has, however, mainly been the return research of reared salmon.

The fisheries around the country have revealed very limited bycatches of salmon.  The greatest occurrances are of the south and west coasts during spring and autumn.

The salmon runs upriver from May to October, mostly during the middle of the period.  The time limit is narrower in many areas, where natural circumstances deviate, i.e. lack of water and low temperatures.  Hight tides and floods sometimes increase salmon runs.  Some rivers have automatic counters.

The salmon's spawning depth is 15-120 centimetres.  Gravel bottom, 60 cm, and minimal current are the most advantageous circumstances.  The hatching speed depends on the water temperature and is measured in °/days.  The size of the roes of the Icelandic salmon is best explained by the quantity of one litre per spawner, which is 7000-9000, depending on its body size.

The number of fries in Icelandic salmon rivers has been research widely and eminently exceeds rivers of other countries.  After the fries have finished the feeding pouch, they feed on larvae and chrysalis of insects.

The productivity of Icelandic rivers depends on their volume, temperature and stability.  Therefore one might think, that many of them were limiting because of floods or lack of water, which limits access to food.  Birds, minks, foxes and seals also take their toll, and other living creatures compete with the salmon, when it comes to feeding.

The age of the fries is usually three years, when they turn to sea, but can reach 5 years, when their size is 11-14 cm.  The salmon stays 1-3 years in the ocean, or until it reaches puberty.  The number of salmon spawning more often than once is various, depending on rivers, between 0%-18,4%.  Their weight after one year in the ocean is between 1,5 and 3,5 kilogrammes, but 4-6 kilogrammes after two years.  Larger salmon have spent more time in the ocean.  The theory, that the strength of each generation does have something to do with this, is widely spread.

The first hatching station in Iceland was built on river Laxa in Kjos in 1885.  More followed, but were not successful because of lack of knowledge and shortage of man power.  The Alvidra station was built in 1922 and continured for four decades.  The Ellidaar station started in 1932 and is still in operation.

The first attempt at rearing salmon was carried out in the northeast during world war II, but was discontinued.  In 1944 it was attempted in Borgarfjordur, and in other places without any mentionable results.  In 1952 an open air rearing was added to the Ellidaar project to produce one summer old fries for realease.  In 1964 indoor rearing was started there.

The Kollafjordur station started in 1961.  Since then, many have began with different results, and many went bankrupt.  The following were among the first:  Ellidaar (1966), Laxamyri (1972), Tunga (1965), and Oxnalaekur (1971).  In addition there were others, which concentrated on hatching (Laugarbakki near Selfoss; 2.000.000 roes yearly).  In Laros (Snaefellsnes), fries were released and left to thermselves until they swam to sea.  Fry releases were and are considerable, and gradually tagging has revealed the returns.