Salmon Life Cycle

The River Wye is famous for its salmon. Record catches have been made on the river and the salmon's life cycle is a fascinating, amazing tale of endurance

Spawning
Salmon lay large numbers of eggs upstream in the river Wye and in the smaller rivers that run into the Wye. Where the river bed is suitable in autumn to winter the female will make a space in the gravel with her strong tail and lay her eggs. The male fish will then release sperm over the eggs to fertilize them and the eggs are then covered with gravel to a depth of several centimetres by the female. The eggs are then left alone in this gravely watery nest called a ‘redd.’

Eggs
The eggs are about the size of a pea and begin to grow. By January to February to black dots appear, the eyes, but it will not be until March to April before the eggs are ready to hatch.

Alevins
The just-hatched fish are called alevins, and still have a yolk sac attached to their bodies, with the remains of food supplied from the egg. When most of the the yolk sac has been eaten, the alevins begin to move through the gravel. They soon grow all eight fins, which will be used to maintain their position in fast flowing streams and manoeuvre about in the water. 

Fry
Once the young fish begin to swim freely (three to six weeks after hatching), they are called fry. Their survival depends on the water temperature and if they manage to find enough food and escape being eaten themselves.

Parr
Fry quickly develop into parr with vertical stripes and spots for camouflage. They feed on insects that live in the river and grow for one to three years in the same part of the river from which they hatched. Once the parr have grown to 10–24 cm in body length, they undergo a change inside their bodies which will help them to survive in salt water. This is called smolting.

Smolts
The fish begin to look different their bodies are now silvery and change from swimming against the current to moving with it. This change prepares the smolt for its journey to the ocean. The smolts will leave the river in spring to the Atlantic where they will feed on herring and sand eels, until finally reaching adulthood and returning to the river.

Adult Salmon
It takes salmon two or more years to mature and return to the river. This amazing ability to locate their ‘home river’ is achieved through using the earth’s magnetic field and through sensing a chemical trail left in the river called pheromones. The Salmon no longer feed once entering the river they are now heading for the spawning grounds to begin the cycle again. A journey of up to 5000km makes salmon "the king of fish".

Kelts
Having spawned, the salmon are referred to as "kelts". Now they are weak, having not eaten any food since their arrival in freshwater and losing energy in a bid to reproduce successfully they can become ill or be caught by predators. Many die especially males but some do survive and commence their epic journey again.