Since the end of the Second World War, coral reefs of the Indo Pacific and especially the South China Sea have been subjected to dynamite or blast fishing.
Originally, blast fishing used commercial dynamite or other explosives but in recent years the trend has been for fishers to make their own bombs using artificial fertilizer.
The bombs are usually on 5-second fuses and are dropped into the centre of an area judged to have many fish. After the bomb has exploded, the fishers use dip-nets to collect the stunned and dying fish, either from the boat or underwater.
The fishers do not blast at random but choose the site carefully for maximum catch.
Blast fishers hunt by preference for schooling fish, so larger fish such as sweetlips and groupers which aggregate in groups and hide under large coral heads are specific targets.
Schools of fish visible in open areas are also targeted; butterfly fish and schools of fusiliers which stream along just above the reef slope or parrot fish and surgeon fish schools grazing on the reef crest are actively sought.
|In both Sabah and Indonesia, fishing boats can be divided into three main types:|
|one-man, one-boat operations which operate over a very small area|
|medium scale operations that have larger boats with a crew of 3-5 but are still restricted to reefs within a one-day radius|
|large-scale operations that have boats with living and sleeping facilities and with up to 20 fishers per boat; they make trips lasting several days and cover large areas|
Many larger boats collect the fish using “hookah” compressors with long air hoses supplied to divers working underwater. Banning the compressor has been suggested as a simple regulation to reduce destructive fishing.
Fishing boats preparing for sea and loading with fertilizer are common in villages close to Kota Kinabalu, Sabah. Fishers from the Philippines purchase fertilizer, diesel and kerosene in Kudat, North Sabah, en route to their blast fishing sites in the Philippine Spratley Islands. From Zamboanga City in the southern Philippines, boats travel on 4-6 week trips blasting at all reefs with sufficient fish .
Boats from all the coastal towns in Sabah do the same! Blast fishers from Sandakan were watched as they systematically destroyed a remote offshore reef at a rate of 15 bombs per hour. Not surprisingly, there was only a large rubble pile left instead of a coral reef after this attack.
As they floated to the surface, the dead fish were collected by 12 small boats equipped only with dip nets. Most often, dead fish that sink to the bottom and are out of reach of the dip nets are simply left to rot on the seabed.
Observations like this reinforce the views of the local fishers who believe they have no option but to continue to blast when their reefs are subject to severe damage from wide ranging, larger boats.
Reefcheck Malaysia reports blastfishing in 2011
TRACC completed a lot of Coral reef surveys – learn more