The often illegal but prevailing method of dynamite fishing is sending shock waves through the conservation and outdoor sports communities.
A common problem in impoverished parts of the world, dynamite, or blast fishing occurs when locals detonate underwater explosives to kill or stun fish in large numbers. In areas where food is scarce but explosives are plentiful, blast fishing is an effective means of harvesting several fish with minimal effort.
However, the method is causing irreparable damage to natural environments worldwide. It can destroy large sections of coral reefs and kill far more fish than can be harvested. The explosives rupture fish bladders and internal organs, causing them to sink to the bottom. Many fish are not killed outright, but left disoriented and flopping around in shock.
Because of the indiscriminate nature of these explosions, other species not targeted by fisherman are often caught in the crossfire. Species with dwindling numbers that are crucial to the ecosystem are often killed along with the more plentiful fish.
Fishermen can obtain explosives from all kinds of sources, including local mining and construction projects. Often the explosives are cheaply made, consisting of nothing more than a glass bottle filled with powdered potassium nitrate and pebbles and dropped overboard. Locals’ crude explosives often literally blow up in their face, causing injury or death.
The sounds of blast fishing can alarm tourists. Visitors to places like Lebanon and Tanzania often report hearing the loud explosions from locals seeking out a meal. In some cases, scuba divers and swimmers can even feel the shock waves from nearby blast fishermen.
Concerns over the impact to their environment and their tourism industry are motivating governments to crack down on blast fishing, although enforcement can be difficult. While the source of explosions is usually easy to to hear, it is more difficult to locate along miles of coastline. Some perpetrators have also taken to fishing only at night and dropping explosives at deep depths to avoid detection.
Authorities and conservationists are employing underwater microphones to help zero in on where blast fishing occurs. Tanzania, Indonesia and the Philippines have begun patrolling waterways to catch or deter blast fishermen. Cambodia has also educating locals on why blast fishing can threaten their livelihood. Some conservationists have also proposed banning or regulating the sale of the materials used to make underwater explosives. While all these methods have seen some success, the harmful fishing technique remains common in in parts of Southeast Asia
Like many conservation issues, the problem is driven not as much by locals’ greed or selfishness, but desperation. The challenge going forward will be convincing blast fishermen that their method may mean food on the table in the short-term, but in the long run could starve their communities.