Fig. 4. Influence of ashfall on fish biomass. (Redrawn from data by D.C. Ochavlllo,
H. Hernandez and P. Allho)
The heavily-silted Daan-Bapor River in Sasmuan, Pampanga. This river used
to be 20-feet deep. (Photo courtesy of PCAMRD-DOST),
Inland Fisheries and
Aquaculture
Dr. Rafacl Gucrcrro IIIof the PCAMRD-
DOST visited sites in Zambales, Bataan
and Pampanga. The findings confirm
what the UPMSI has reported?
According to Dr. Guererro, river systems
in the three provinces suffered heavy
Sillation (photo) and change of flow
pattern, affecting fresh- and Brackishwatcr
fishes and invertebrates. About 6,000
ha of freshwater and 26,000 ha of
brackishwater fishponds experienced
siltation, cut-offs from irrigation∕tidal
waler,poor drainage, and became prone
to flooding, threatening culture operations
in Nile tilapia, carp, milkfish and shrimps/
prawns. Municipal fishers reported a
sulfuric flavor in fish catch. In general,
there were no fish kills directly caused
by the ashfall, but fish catch declined
due to the effects on fish habitat.
PCAMRD recommended short- and
long-term rehabilitation measures such
as dredging, introducing seafarming and
installing temporary artificial reefs.
What Next?
The story is far from over. Various
agencies arc continuing studies on the
effect of volcanic materials on plankton,
seagrass, mangrove, giant clams and on
marine chemistry.
With these initial findings alone, the
Philippine government, already saddled
with the restructuring of agriculture and
infrastructure, has much more work to
do.
New Ecosystem
Mt. PinatubolSeruption has also brought
forth new ecosystems, PC AMRD reports.4
One of these is a 1 ,OOO-ha "lake" in San
Marcelino, Zambales1 created out of a
small river tributary whose outlet has
been blocked by lahar. Pinatubo Lake,
as it is now called, averages 3.5 m deep
but reaches up to 8-10 m in some portions.
PCAMRD has assessed the lake and
found it to be suitable for fish cage
culture. Plans for a pilot project for
tilapia culture are now underway.
Acknowledgements
Acknowledgement is hereby extended
to the authors of the studies cited for
unselfishly sharing with∕√αgα the initial
reports of their studies, before their
presentation at international symposia.
Further Reading
1Atrigcnio, M., P. Alino and R. Bina. 1991. Assess-
ing the damage caused by the Mt. Pinatubo1S
eruption on the nearby reefs using remotely
sensed data. Paper submitted to the First The-
matic Conference: Remote Sensing for Marine
and Coastal Environments, 15-17 June 1992,
New Orleans, Louisiana, USA.
2Ochavillo1D.,11. HemandezandD. Alino. 1991.Tlte
effects of the Mt. Pinatubo eruption on the coral
reef fish communities of Zambalcs. Paperto be
presented at the ASEAN-Australia Coastal Liv-
ing Resources Second Regional Symposium,
21-23 September 1992, Singapore.
2Gucrcrro, R.D. 111. 1991. Executive summary of
the impact of Ml. Pinatubo1S eruption on the
rivers, fishponds and municipal fisheries of
Zambalcs, Bataan, and Pampanga. Philippine
Council for Aquatic and Marine Resources
Development, Department of Science and Tech-
nology, Manila, Philippines.
4PCAMRD. 1991. PCAMRD recommends tilapia
fish culture in 11Pinatubo Lake". PCAMRD Waves
4(4):1-5.
C. Infante-Guevara is Editorial
Assislantfor ICLARM'sInformation Program.
10
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