Animal Profiles
Fish

Trout

Living

Living individuals or members of this group exist today. This does not mean they are safe from extinction.

Trout is a familiar name for several related fishes. This account describes rainbow trout, including the sea-going steelhead form, which shares the same species name rather than being a separate species.

Rainbow trout (Oncorhynchus mykiss), the representative described here.

Rainbow trout (Oncorhynchus mykiss), the representative described here.

At a glance

Location
The representative is Oncorhynchus mykiss. Native populations occur around the northern Pacific, including western North America and Kamchatka. Sea-going forms connect freshwater habitats with coastal waters. Introductions have spread the species widely beyond that region.
Habitat
Rivers and lakes, Coast, Open ocean
Diet
Carnivore
Food
Aquatic insects and other invertebrates feed young and resident fish, while larger fish also take fish prey.

Classification

Common name
Trout
Browse group
Fish
Scientific name or taxon
Not specified in the source index
Source classification
Actinopterygii

Three things to know

  • Steelhead and rainbow trout are one species.
  • Eggs develop in gravel.
  • Sea-going fish become more silvery.

Habitat and range

The representative is Oncorhynchus mykiss. Native populations occur around the northern Pacific, including western North America and Kamchatka. Sea-going forms connect freshwater habitats with coastal waters. Introductions have spread the species widely beyond that region.

Appearance and adaptations

Dark spots and a pinkish side stripe are common in freshwater fish. Sea-going steelhead are more silvery. Colour varies with age, sex and habitat rather than following one fixed pattern.

Diet and behaviour

Aquatic insects and other invertebrates feed young and resident fish, while larger fish also take fish prey. Eggs develop in gravel nests. Steelhead return to freshwater spawning areas after growing at sea.

Sources

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