Spotlight: Identifiable Features of Juvenile Salmon

1. Identifiable Features of a Juvenile Salmon

Diagram-Identifiable-Features-of-a-Juvenile-Chinook-1100px

How this Chinook Compares with Other Juveniles

The following physical characteristics apply while these juveniles are rearing in freshwater.**

Chinook Gallery

  • Parr marks are oval and wider than the spaces in between.
  • Dark spotting on both lobes of tail.
  • Migrate out to sea after one year (yearlings) or after a few months (sub-yearlings).

Coho Gallery

  • Parr marks are oval but narrower than the spaces in between.
  • Little or no spotting in lower lobe of tail.
  • Leading edge of both the dorsal and anal fin are white with a black line behind that.
  • The first rays of the anal fin are exceptionally long, giving the fin a sickle shape.
  • Migrate to sea as yearlings (after one year).

Sockeye Gallery

  • Faint parr marks extend well below lateral line.
  • No spots on back
  • Adipose fin is clear, not pigmented
  • Can migrate to sea after a few months (if they have grown very quickly) but most migrate out after a year.
  • Unlike other salmon, sockeye rear in lakes before going to sea.

Pink Gallery

  • No parr marks
  • No spots on their back
  • Back may be greenish, but not below lateral line.
  • Migrate to sea as fry, as do chum.

Chum Gallery

  • Faint parr marks generally above the lateral line.
  • Greenish color on the back extends below the lateral line.
  • Migrate to sea as fry, as do pink.

** Once these juveniles begin migrating to the estuary and to sea, they develop an opaque, silver layer that covers up their juvenile markings, making the species much more difficult to tell apart.

Take the Juvenile Salmon Identification Quiz

Using the galleries above, study the “tiny” differences between the five Pacific Northwest salmon in their juvenile phase. When you are ready, click this image to take our Juvenile Salmon Identification Quiz> > >