The massive fishkills in Taal Lake, Batangas, and in parts of Pangasinan were caused by a five-letter word: G-R-E-E-D. The fish pen and fish cage operators were so greedy for profit that they overstocked their fish pens and cages with fingerlings.
There is so much profit from raising milkfish and tilapia in fish pens and cages that everybody within sight of a large body of water, including overseas Chinese with plenty of capital, went into the business using Filipino dummies. The greed also infected officials of local government units (LGUs) and government agencies supervising the development of the lakes.
Because each fish pen and fish cage applicant paid a fee to the LGU, the LGU officials approved the applications en masse to be able to collect the fees. Not only that; because violators of the rules were made to pay a fine to the LGU and agencies like the Laguna Lake Development Authority (LLDA), the officials themselves encouraged violations. The more violations, the bigger the fines collected. So that instead of discouraging violations, the fines encouraged government officials to tolerate violations.
In due time, because of greed, almost all the bodies of water were overpopulated with fish pens and fish cages so that the carrying capacities of the lakes were overloaded.
Unlike the standard fishponds of old that required plenty of capital and real estate (the ponds have to be dug or diked in foreshore areas), fish pens and cages require only some bamboo and netting in a small piece of lake. And for such a small investment, compared to the investment and work in the standard fishponds, the profits are so huge that the ever-greedy fish pen and fish cage operators, after the first harvest, seek to increase their profits by increasing the number of fingerlings in their pens and cages well beyond the carrying capacity of the lake.
At first, however, because the fingerlings are still small, they thrive. But as they grow bigger, there is overcrowding. Like humans and other animals on land, fish also breathe oxygen dissolved in water. But as in the case of overcrowding on land, the fish also breathe less oxygen in water and die. That’s the fishkill. The fish die of asphyxiation, lack of oxygen.
Fish pen operators make things worse by overfeeding the fingerlings. They think that by feeding the fingerlings more—with fish meals or chicken manure—they will grow faster and bigger, hence, more profit for them. Wrong.
The commercial feed and chicken manure not eaten by the fish merely sink to the bottom and decompose, consuming more of the oxygen dissolved in the water. Thus, the oxygen for the fish is reduced faster. When the oxygen is depleted, the fish die by the thousands.
In the old fishponds, the milkfish eat the moss or algae called lablab planted in the mud. As the fish grow, so do the lablab, so there is no shortage of food for them. There is no need to supplement their food supply with commercial feed or chicken manure. Better still, when there is an oversupply of lablab, they do not decompose like manure or fish meal. They just spread in the pond like grass on land and the fishpond owner simply harvests them and transplants them to ponds with a shortage of feed.
Also, in the ponds, the owner knows the carrying capacity of each pond, so he does not overstock them. There is rarely any fishkill in the standard fishponds.
Yes, there are sometimes fishkills in the fishponds (though never in the magnitude as the fishkills in the lakes) but they are rarely caused by overstocking but by a sudden and extreme change in the water temperature. Or by the failure of a worker to open or close the sluice gates of the fishponds that feed fresh river water into the fishponds.
Saline water in the ponds have to be changed regularly, or else the milkfish would die. This is done during the high tides and low tides. The sluice gates are opened during high tides so that water will come in from the river. During low tides, the water cannot flow out, the pond water is changed regularly. The high tides and low tides occur at different times depending on the phases of the moon, so workers sleep in huts beside the sluice gates and wake up when it is time to open or close the gates. If a worker oversleeps and forgets to open the gates to let fresh water in, the fish die and there is hell to pay.
The same situation does not exist among the fish pens and cages in the lakes. Because the water is free-flowing in the huge bodies of water, there is no need to open and close sluice gates. All the owner and his workers have to do is to keep feeding the fish and watch his investment grow. Which is how the pens and cages are easily overstocked.
Because the fingerlings—which start at the size of needles (they are caught in fine-meshed nets spread in rivers and foreshore areas)—grow fast, the fish pen owner gets greedy and increases the number of fingerlings in each pen or cage, hypnotized by the profits in his mind, not realizing that as the fingerlings grow bigger, they would need more space and more oxygen. By the time the owner notices the first fishes start dying and floating, it is too late. By the next morning, more fish die and there is little the owner and his workers can do to save them. That’s the massive fishkills that we just had.
So what should we do? Should we dismantle all the fish pens and cages in the lakes as former and present environment secretaries have recommended? No, but certainly the number of fish pens and cages must be reduced drastically, confined to the middle of the lakes and leaving the foreshore areas to the subsistence fishermen.
As we have seen, the fish pen industry did not benefit the small fishermen but only the rich businessmen and even foreigners because of Greed!
We should change all that.