Sockeye Salmon

• biologíaIt changes colour dramatically, from silver to deep red, as it nears the end of its life on the spawning migration, after which it dies.
• It returns to spawn in the very stretch of river where it hatched, navigating first by the Earth's magnetic field in the open sea and then by smell, which lets it recognise the chemical signature of its natal stream.
• It is semelparous: it breeds once and dies. The carcasses bring the river nutrients of marine origin that feed bears, birds and the riverside forest itself.
• Before spawning it changes appearance completely: the body turns deep red, the head green, and the male develops a hump and a hooked jaw.
• Populations that stay in lakes and never go down to the sea are called kokanee, and they are much smaller.
• It is the salmon most dependent on plankton: it feeds mainly on zooplankton, not fish, which makes it especially sensitive to changes in the productivity of lake and sea.

Skeleton type

Vertebrate - internal bony skeleton (bony fish)

Habitat and environment

Anadromous: it hatches in rivers and lakes of the North Pacific, migrates to sea and returns to its river of origin to spawn and die; there are non-migratory populations that spend their whole lives in lakes

Sexual maturity

2 years

Sources consulted: Wikipedia (es): Oncorhynchus nerka

The pins mark the parks and dive sites where its presence is documented.