Jakarta scoops tons of invasive fish from its dirty rivers

Jakarta has launched a campaign to pull tons of an invasive fish out of its rivers and reservoirs, a small window into the city's water problems. As the Associated Press reports, the city governor, Pramono Anung, ordered the removal of at least 10 tons of "janitor fish," known locally as sapu-sapu, and more than 7 tons were scooped out within a week.

The fish are not just a nuisance. An ecologist, Dian Rosleine, called them "biological indicators," meaning their presence signals poor water quality in Jakarta's heavily polluted Ciliwung River. Officials also say the bottom-feeding fish damage the banks and walls that hold rivers in place. Even the cleanup sparked debate: the Indonesian Ulema Council objected to burying the fish alive, so the rules were changed to require the fish be dead first.

The city is now looking at what to do with the huge catch, from turning it into animal feed or fertiliser to making charcoal. Behind the odd story of a fish hunt is a bigger truth: Jakarta's waterways are unhealthy, and the invasive fish are a symptom of years of pollution.

Why it matters

For people who live near Jakarta's rivers, the health of that water affects flooding, smell, and disease, so a cleanup is welcome even if the fish are only a symptom. The real fix is cleaner water, not just removing what thrives in dirty rivers. Watch whether the city tackles the pollution behind the problem, or just the fish.