Rizal Province directory, Volume I.

BANGOS INDUSTRY
* The Bangos culture, to which the towns of Malabon and Navotas
owe much of their prosperity and which has been a source of considerable income to the government was originated by Sr. Domingo Coronel.
About 1863 this pioneer constructed the first bangos pond in Concepcion,
Malabon. After some years the industry spread to the neighboring towns
bordering Manila Bay.
The reasons for its confinement along the coastal towns are not difficult to seek. The mangrove and nipa swamps along the coasts are very
favorable to moss growth (spyrogyra) on which the fish feed. Besides
there is mud suitable for dike construction and water for the ponds from
the rivers that empty into the bay is available throughout the year. The
sea water raises the salinity of the pond sufficiently to discourage the
growth of the "dalag" fish which preys on the growing fry.
A typical fish pond covers an area of several acres. High and strong
dikes surround it to retain water, withstand inundation, and avoid overflowing of the ponds during rainy season. The pond is divided into several
compartments by dikes and are provided with small sluice gates for water
communications. At the mouth of the river or estero there is a main
sluice gate with which the caretaker regulates the in and out flow of
water. The square or rectangular compartment immediate to this gate
is the "Kulungan". Smaller sluice gates constructed along its dikes connect it with the other compartments ralled the "IKuluangan" which are
the ponds proper where the bangos are raised to marketable size. One
compartment is called the "impitan" where the fry are detained
until the "Kaluangans" have grown sufficient "Lumot." The "Impitan"
may serve as "Bansutan" where the fry are returned due to the shortage
of "lumot" in the "Kaluangan." A canal runs from each sluice gate diagonally or in the longest distance possible to every compartment. The
floor of the compartments are so sloped gradually down the canal as tc
insure complete drainage whenever necessary, to provide a cooler depth
of water for fish to retreat during hot hours of the day, and to serve as
collector during catching time.
The fry are imported from the coasts of Bataan, Batangas, Mindoro,
Tayabas, Zambales and the Ilocos. From March to the latter part of
May, the' spawners or female bangos discharge their eggs along the
shores and are fertilized by the milters or male. Shore conditions are
very favorable to propagation. The fry are called "KIawagkawag" and
are caught by means of sagap, seive like devise of coarse sinamay or by
saplad a V shaped bamboo device to which the fry are forced to retreat.
The fry are sorted, counted and sold in earthen jars.
The transplanting and the rearing of the "Kawagkawag" until they
become "hatirin" or fingerlings of two to three months old and require
the most careful attention. The fry are so weakened materially during
the transportation that an abrupt change of conditions may prove fatal
to them. When the fry nursery has grown sufficient "lablab" already
and the weather promises to be fair, the fry are carefully poured into the
pond while a free circulation of water takes place through the pipes es* Excerpts talen from the Phil. Journal of Science.
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