The illustrations indicate how salmon are born and their physical development after a few years to become adult ones. In general, the life cycle of salmon happens at various places in the water as they grow up, which contributes to different changes in their body size.
As can be seen from the illustrations, the first step occurs in the upper river where the water flow is quite slow and there are various reeds. This stage lasts for roughly five to six months when salmon eggs are laid in small stones under the reeds. This will probably help to protect the eggs from predators until they are born until these eggs become fry, which is tiny salmon sizing from around three to eight centimetres.
The next phase of salmon’s growth takes place in the lower river where the flow was much faster; besides, this phase may last for around four years. After this period, those salmon fry may turn into smolt whose length is about 12 to 15 centimetres. Then, these smolts may swim to the open sea and continuously improve their physical size to 70 to 76 centimetres. These adult salmon may swim back to the upper river to give birth to their offspring and this natural process recurs.