Bonito, Pacific (lat. Sarda chiliensis)
The Pacific bonito is an important gamefish, valued more
for sport than for food, as is the Atlantic bonito.
OTHER NAMES:
California bonito, eastern
Pacific bonito, bonehead,
Laguna tuna, striped tuna,
ocean bonito; French:
bonite du Pacifique; Japanese:
hagatsuo;
Spanish:
bonito del PacĂfico.
Similar in size and pigmentation to the
Atlantic bonito, the Pacific bonito is distinguished from
most other bonito by the lack of teeth on its tongue and the
possession of a straight intestine without a fold in the middle.
The Pacific bonito has 17 to 19 spines on its first dorsal
fin and is the only tunalike fish on the California coast that
has slanted dark stripes on its back. Like other bonito, its
body is cigar shaped and somewhat compressed, with a
pointed and conical head and a large mouth. It is dark blue
above, and its dusky sides become silvery below.
Pacific bonito can grow to 25 pounds and 40
inches, although they are usually much smaller. The alltackle
world record is 14 pounds, 2 ounces. Fast-growing
fish, bonito will be 6 to 10 inches long by the early part of
their first summer, weighing 3 pounds by that fall and 6 to
7 pounds the following spring.
Pacific bonito form schools by
size; at 2 years old, they reach sexual maturity. Spawning
occurs sometime between September and February.
Although spawning is usually successful each year in the
southern part of their range, it may not be successful each
year farther north. The free-floating eggs require about 3
days to hatch at average spring water temperatures.
Pacific bonito prey on smaller
pelagic fish, as well as on squid and shrimp, generally in surface
waters. Anchovies and sardines appear to be their preferred
foods.
Pacific
bonito occur discontinuously
from Chile to the Gulf of
Alaska. Their greatest area
of abundance occurs in the
Northern Hemisphere in
warm waters between Magdalena
Bay, Baja California,
and Point Conception, California.
Bonito live in surface
to middle depths in the
open sea and are migratory.
Older fish usually range farther
from the coast than do
juveniles. Bonito may arrive
off the coast in the spring as
ocean waters warm, but
they may not show up at all
if oceanic conditions produce
colder than normal
temperatures.