Pasig River Rehabilitation Commission (PRRC) personnel got a huge surprise when they caught a giant tilapia from Manila’s Estero de San Miguel (San Miguel estuary) yesterday morning.

A photo of the fish posted by the PRRC on Facebook shows that it was almost as long as the top half of a woman’s body. According to the commission, the tilapia was 20.5 inches (52.07) in length and weighed 3 kilos.

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The PRRC said that this is a sign of positive change in Manila’s polluted rivers.

“We really are already seeing a positive change in our rivers because we’ve come together to revive and take care of them. Let us continue these good works and surely we will be blessed by the environment,” it said in Filipino.

The 27-kilometer Pasig River is notorious for being very polluted and was even declared biologically dead in the 1990s.

However, Sonny Batungbacal, regional oceans research coordinator for Greenpeace Southeast Asia, told Coconuts Manila in a phone interview that seeing one giant fish is not enough indication of a clean river.

He said that this might have just happened by chance and that the fish could have just escaped from a nearby fish pen. For a better read of how the river is doing, Batungbacal said that we must know how much fish is in the water.

He said the best way to measure the health of the Pasig River is to check its water clarity. It should be transparent and there should be minimal floating plastic garbage.

Batungbacal believes the PRRC is doing its best to improve the river’s quality. “In fairness, the cleanliness of Pasig River has improved,” he said.

In 2018, the PRRC’s rehabilitation project was even given the Asia River Prize Award by the International River Foundation for successfully reviving the water body.

Batungbacal said the commission can only do so much so it is important for communities near the river to help keep it clean as well.

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This article, BIG FISH: Giant tilapia caught in Manila’s Estero de San Miguel , originally appeared on Coconuts, Asia's leading alternative media company. Want more Coconuts? Sign up for our newsletters!