334 Fish as feed inputs for aquaculture – Practices, sustainability and implications
- Between Callao and San Juan, the distribution of the Chilean jack mackerel is very
limited; they are mainly found off the coasts of Pucusana, Cerro Azul, Tambo de
Mora, Punta Paracas, Punta Caballas and San Nicolás, at a distance of between 3
and 60 nautical miles. - Between San Juan and Tacna, their distribution is very limited, Chilean jack
mackerel being mainly found in Lomas – Punta Chala, Quilca, Matarani – Punta
Bombón and Punta Coles between 2 and 6 nautical miles.
South American pilchard or sardine, which were previously an important commercial
species, are mostly found in the north from Sechura Bay and the Galapagos Islands to
Valparaiso, Chile, in the south, and up to 200 nautical miles off the coast. The areas
of higher concentration are located south of Paita, from 60 to 70 nautical miles off the
coast; in Pimentel, Eten, Salaverry and Huarmey between 6° and 10°S latitude; and in
Punta Caballas and San Juan between 15° and 16°S latitude. They are found in waters
with temperatures ranging between 14 and 25°C and salinity between 34.8 and 35.3
ppt, ranges that are wider than those of the anchoveta. Juveniles of this species can have
a maximum total average length of 21 cm. This species tends to dwell in areas similar
to those inhabited by the anchoveta.
Another species is the chub mackerel, for which there is limited fishing information
in relation to its biological behaviour. This species is mainly used for direct human
consumption and is distributed from Manta, Ecuador and the Galapagos Islands to
Valparaiso, Chile.
2.4.2 Fishing seasons
October is the month of final spawning for anchoveta and is when the fishing season
normally starts. Although the spawning season of the anchoveta runs from August
through March, the peak months are August–September and February–March;
therefore, these months are normally declared as a closed season. A similar annual
cycle occurs in the case of sardine. Their capture is restricted during the same months
as those of the anchoveta. The other small pelagics – Chilean jack mackerel and chub
mackerel – generally have no fishing restrictions, as these fisheries are regarded as
underexploited.
The largest catches of these resources (except the anchoveta) are made in the months
of January through March, unless there are favourable oceanographic conditions in
other months of the year. However, in general the fishing season is quite consistent
from year to year.
The distribution of anchoveta biomass is coastal between depths of 0 and 60 m
(Ñiquen and Bouchon 1991). In spring and summer, anchoveta occur mostly within
the 30 mile limit, while in autumn and winter they are widely dispersed, reaching up
to 100–120 miles from the coast when the cold waters prevail and homothermic and
homohaline conditions exist. The main fishing areas are located between 7–8°S and
11–12°S latitude and are associated with temperatures of 16–20°C and salinities of
34.9–35.1 ppt. Anchoveta are highly gregarious, forming large and extensive shoals that
facilitate their capture. The El Niño drastically affects stock distribution, with stocks
moving closer to the coast, into deeper waters and finally southward to 10°S latitude
(Ñiquen and Bouchon, 2004).
Anchoveta live to 3 to 4 years of age, but are usually captured when they are 1
to 2 years old. The size structure of individuals in the north-central stock fluctuates
between 10 and 18 cm. Sexual maturity is reached at a length of 11–12 cm and an age
of one year. The main spawning areas are located between Chicama and Chimbote and
between Callao and Pisco. Spawning occurs throughout the entire year, with peaks in
August–September and February–March. The largest spawning stock is observed from
December to April.