Pacific Chub Mackerel (Scomber japonicus) — identification, habitat & look-alikes

Pacific chub mackerel is a schooling saltwater fish of the U.S. West Coast, with dark wavy stripes on its back and a silvery belly. Along the U.S. West Coast, Pacific chub mackerel is also widely called Pacific mackerel.

Appearance

Appearance: It has a pointed head, dark blue back with wavy lines, and a silver green underside. Small line the body just before the tail.

Look-alikes

Pacific jack mackerelTrachurus symmetricus

Pacific chub mackerel has dark wavy stripes across its back. Pacific jack mackerel lacks that pattern and has a line of large, rough scales along its side toward the tail.

Why they get mixed upBoth are silvery schooling fish that occur together off California.

Where it lives

Typical habitats: coastal open water
shallow banks
bays for young fish
Range: It lives off the U.S. West Coast, especially California, and moves north toward Washington in summer.
Preferred conditions: Off California, it is often found within 20 mi (32 km) of shore in water around 50–72°F (10–22°C).
Migration: Adults move north in summer and south toward Baja California in winter.
Seasons: In California
Breeding Apr–Sep

Behavior

Diet: Off California it eats plankton and young fish, including anchovies and sardines.
Social life: It gathers in schools, sometimes alongside Pacific jack mackerel (Trachurus symmetricus) and sardines.

Life cycle

Breeding season: Off California, spawning runs from late April through September.
Reproduction: A female can release several batches of eggs in a year.

Conservation

IUCN Red List: LCLeast ConcernLow risk of extinction

10 sources