Pacific Bonito
Sarda chiliensis

Physical Description

• Large fish with compressed, tuna-shaped body and a pointed, conical head with downward-slanting mouth.
• Blue to violet coloration on back, with ten or eleven silver-blue stripes on back running obliquely from the back fin forward.
• Short, long, black dorsal (tail) fin that runs almost whole length of fish.
• Can be up to 40 inches long, and weighing up to 25 pounds.

Range

• From Alaska to tip of Baja California, Mexico.
• Not common north of Point Conception.

Habitat

• Found anywhere from inshore to about 100 miles offshore.
• Can be in depths of 300-600 feet.

Reproduction

• They reach sexual maturity at age 2.
• Spawning generally from late January to May.
• Eggs float freely in top 300 feet of water.
• Eggs usually hatch within 4-5 days after spawning.

Diet

• Small schooling fishes, such as sardines and anchovies, squid, shrimp.

Predators

• Larger fish such as tuna, as well as other bonito.
• Humans (fished for sport and for seafood).

Interesting Facts

• Bonito populations heavily fluctuate with warm and cold water, which often fluctuates with atmospheric fluctuations like the Pacific Decadal Oscillation.
• Unlike most fishes, they have no swim bladder.
• They often swim in large schools.

Sources: California Sea Grant; FishBase; California Department of Fish and Wildlife

Photo: Paula Selby