The illustrations depict the four steps of biological life cycle that occur in massive fish called salmon.
Overall, these aquatic baby animals hatch in safer areas of the river and live in the sea as the adults before returning to the shore to lay eggs again.
In the first phase, the eggs are placed between tiny stones, protected by long reeds above them. This lasts about 5 to 6 months for the pupa to come out from the shell, which can be up to 8 cm long. Then, these young fish relocate to the bottom part of the river where water flow is speeding up, staying here for nearly 4 years until these become smolt.
After this phase, the salmons change their habitat again to move to the open sea, and spend about 5 years in the ocean to transform their size that can reach 76 cm at most. Finally, this group of aquatic animals go back to the shallow stream to give birth to their children and for several times, the cycle repeats itself.