t may not be
a major method of fishing like hook and line or the gill net, but explosive
fishing is widespread in the Philippines. According to one estimate, about
70,000 fishers - that's 12% of the total number of capture fishers in
the country - are suspected to engage in blast fishing. In every bay and
in every gulf, there are always blast fishers; for every fishing ground,
there is always a village known to be the residence of blast fishers;
and in every village, there is always at least one tale of misfortune,
of a blast fisher or another person maimed or killed because of the explosion.
The practice, of course, is illegal. Worldwide, underwater explosives
find their legitimate use in the demolition of abandoned oil platforms,
clearance of navigational obstruction, and conduct of military exercises.
In the past, the use of explosives to collect fish specimens was even
allowed. For example, in 1907-1910, the Philippine expedition of the United
States Bureau of Fisheries steamer Albatross used explosives to gather
reef fish samples. Two defunct fishery laws, Act No. 4003 (1932) and Presidential
Decree No. 704 (1975), allowed the use of explosives for research and
eradication of "whales, crocodiles, sharks or other large dangerous
But the use of explosives for fishing has never been sanctioned by law.
The current applicable law, Republic Act No. 8550 (the Philippine Fisheries
Code of 1998), penalizes the use of explosives with imprisonment of 5-10
years. In addition, the perpetrator forfeits his boat, equipment and catch
to the government, and if the explosion injures or kills people, he can
be charged with a separate criminal case. Also, the marketing of fish
caught by explosives is punishable with imprisonment of 6 months to 2
years, and so is the unauthorized possession of explosives.
The law, however, has not stopped blast fishing, whether in the past,
when penalty was harsher (20 years to life imprisonment) or in the present,
when penalty has been made humane because of the belief that all blast
fishers are poor. Enforcement has been a major issue. Only a few blast
fishers have been apprehended, and fewer still have been convicted. Often,
those unfortunate ones who are caught are mere followers or underlings
- the "big fish" usually gets away.
Profile of the blast fisher
Contrary to widespread belief, blast fishing is not practiced exclusively
by impoverished sustenance fishers. In fact, the blast fisher may be socio-economically
better off than a gill net user. He may be a ring net user or purse seiner,
who uses explosives to stun schools of fish attracted to floating fish
aggregating devices. He is a daring individual belonging to a tightly
knit group enjoying protection from apprehension and prosecution provided
by some higher-status persons who are in business, politics, government
and law enforcement. He is often feared in the community. He may even
be considered a community leader and benefactor who allows other fishers
and members of the community to gather the fish and so get a share of
the catch. The whole community, in fact, may be his accomplice. They warn
him about the arrival of law enforcers. They provide no information and
do not cooperate in the investigation.
Explosives are powerful and dangerous tools to use under any circumstances,
and blast fishers have lost limbs or even died because of defective explosives
or some miscalculation. Moreover, blast fishing has other hazards. Sometimes,
the blast fisher must dive great depths for his catch and thus face the
risk of getting the bends, or, when using a compressor, of breathing oil-contaminated
air. But, without fear of being apprehended or prosecuted, he is willing
to face the risks for the promise of a big catch.
Anatomy of blast fishing
Explosives assure bigger catches because they are used only when there
is a school of fish. When the blast fisher goes out to sea, he also brings
along other gear like hook and line, spear guns, air compressors, poisons,
fish pots and a variety of nets. It is only when he spots a school of
fish or a large fish that he throws or drops the explosive in the water
column. An underwater explosion makes a series of waves that spreads in
the water. An initial high-intensity shock wave is generated, followed
very closely by less severe pressure waves of diminishing intensity that
nonetheless add to the total impact.
The initial wave is produced by the explosive substance undergoing rapid
chemical decomposition, thereby violently creating sound and releasing
a large volume of gas, as a gas pocket, at high pressure and temperature.
Subsequent waves are created by the rapid gas expansion in the water,
causing a sequence of contractions and expansions as the gas pocket rises
to the surface. Meanwhile, the initial high-intensity shock wave travels
outward in all directions from the point of explosion, losing its intensity
The intensity of the waves depends on the particular circumstances (depth,
distance, water temperature, water layers) in which the explosion occurs,
and the type and size of the explosive used. The waves traveling to the
bottom may be reflected back, depending on the kind of sea floor; waves
moving towards the surface either bounce back or break through the surface.
Water turbulence and movement in the area also follow an explosion.
Fish with air or swim bladders - that is, most bony fishes - are the most
vulnerable. The waves of the blast increase the pressure within their
bladder, more so when the fish are near the water's surface. Fish without
bladders (sharks and rays), shrimp, lobsters, crabs and oysters are relatively
Fish taken by blast fishers are both pelagic and reef species, including
anchovies, sardines, scads, mackerels, jacks, mullets, fusiliers, rabbitfish,
surgeonfish, groupers and snappers. They show ruptured bladders and blood
vessels, broken bones and mutilated bodies (especially those very near
Fish encircled by nets are also sometimes blasted before they are hauled
up. The blast exerts tremendous pressure that kills, injures or stuns
the fish outright, making it easier for fishers to hand-pick, scoop or
spear them. Ordinarily, however, fishers are not able to collect all the
fish hit by the explosion. The fish affected by the blast may be distributed
over a wide area, some are carried away by currents, and others may have
sunk to the bottom, too deep for diving even with the use of compressed
air. Or the fishers, suddenly interrupted by the approach of law enforcers,
are forced to flee. In areas outside their influence, blast fishers disappear
quickly from the scene of the explosion, leaving behind a marker which
will guide them later when they return to the site to gather the catch.
Within its relative effective range, the explosion upsets the established
community of organisms, as well as their food webs, as the blast also
strikes non-targeted, non-commercial species, juvenile fish, plankton,
corals, shellfish and other invertebrates, sea mammals, turtles and birds.
An explosion on or near a coral reef physically alters the reef, leveling
and creating a crater, breaking the corals into rubble, reducing its relief
and complexity as a habitat and lessening its aesthetic appeal. Blasted
reefs support fewer fish species and lower fish biomass, thus resulting
in lower fishery production. They also take a long time to recover.
A tradition of destruction
Some blast fishers refuse to believe that the cumulative effect of explosive
fishing is responsible for declining fish catches. Instead, they blame
the government's failure to control commercial trawlers and commercial
fishing using powerful lights. In their view, blast fishing improves their
chances in resource competition. They thus have no qualms about bombing
coral reefs, or even artificial reefs made of tires, concrete and bamboo
that are deployed by the government, non-governmental organizations and
fishers associations as habitat enhancement.
Indeed, in many coastal villages, blast fishing is deeply rooted in tradition.
The practice already existed before World War II, becoming extensive and
rampant after the War when the ammunition, bombs and other explosives
left behind in dumps and wrecks were salvaged and turned into fish bombs.
Glass bottles of various sizes, weighted by sinkers made of iron or stone,
served as casing. The bombs were detonated by home-made or commercial
When war ammunition was exhausted, the fishers began using miner's dynamite,
and then agricultural fertilizers (ammonium nitrate, potassium nitrate
and sodium nitrate) mixed with kerosene, now the most common source. Blast
fishers have also learned to use battery-operated pipe bombs which explode
sideways and suppress the sound of the explosion.
Every year, especially in October, the government conducts a nationwide
public information campaign about the destructive effects of blast fishing.
The national government has also been giving patrol boats (mostly outrigger
boats with inboard motors) to the local governments who, alas, often fail
to maintain them. Furthermore, the national government has trained public
market inspectors and fish traders in how to detect blasted fish.
But still blast fishing continues, partly because of resource depletion
and the deepening poverty in many coastal communities, but largely because
law enforcement has been weak, or at best erratic. Enforcers are poorly
motivated, or else are poorly equipped and ill-trained in taking evidence.
Those who seriously enforce the law can be harassed or even killed. More
perversely, some law enforcers are the blast fishers' protectors.
Clearly, these issues must be addressed and soon. Some say it will take
at least one generation to stop a practice that is rooted in tradition.
That may be so, but however long it takes, the process must begin now.
We must start breaking the blast fishers' tradition of destruction, before
it's too late.
Alcala, A.C. and E.D. Gomez. 1987. Dynamiting coral reefs for fish: a
resource destructive fishing method, p.51-60. In B. Salvat (ed.)
Human impacts on coral reefs: facts and recommendations. Antenne Museum
EPHE, French Polynesia.
Generoso, Ernesto. 1998. Is the gov't helpless vs. 70,000 blast fishers?
The Freeman (October 7, 1998), p.25.
Saila, S.B., V.L. Kocic and J.W. McManus. 1993. Modelling the effects
of destructive fishing practices on tropical coral reefs. Mar. Ecol. (Prog.