Authorities in Jakarta have launched a coordinated operation to remove invasive “janitor fish,” locally known as sapu-sapu, from rivers across the capital. The initiative seeks to restore aquatic ecosystems that have been severely disrupted by the rapid spread of the species.
A City-Wide Mobilization
Ordered by Governor Pramono Anung, the clean-up drive was carried out simultaneously on Friday across all five administrative cities of Jakarta. The effort involved hundreds of personnel and local residents working together to clear the waterways.
In East Jakarta, Mayor Munjirin led a team of approximately 150 personnel, including local officials, firefighters, and disaster mitigation officers. This team focused on the Ciliwung River in Kramat Jati as part of a broader operation targeting 10 locations across the city’s districts.
At the Ciliwung site alone, authorities collected about 200 kilograms of the invasive fish. Following collection, the fish were buried near the riverbank, and officials stated that the operation would be repeated regularly.
Incentives and Local Impact
Similar efforts took place in West Jakarta, specifically within the waterways of Cengkareng. Joint teams utilized nets to capture both adult fish and eggs, collecting around 20 kilograms of fish measuring between 20 and 30 centimeters in less than two hours.
To boost community participation, West Jakarta Mayor Iin Mutmainnah introduced financial incentives. The city offered Rp 25,000 ($1.50) per kilogram of fish collected, alongside rewards for the most successful teams.
The Ecological and Infrastructure Threat
The campaign follows growing concerns over the explosion of janitor fish populations. While popular in aquariums for their ability to consume algae, these armored catfish become invasive once released into the wild, often by pet owners.
Officials warn that the fish outcompete native species by feeding on them and their eggs. Beyond the ecological impact, the fish damage riverbanks and embankments, which may worsen erosion and threaten critical flood control infrastructure.
Future Outlook
City officials have indicated that this coordinated operation is the beginning of a sustained effort to control the species. Future steps may include regular monitoring and consistent removal programs to prevent further ecological damage.
Such measures could be essential for improving river health across the capital, including in areas like Setu Babakan and Kelapa Gading, where Governor Pramono has noted ongoing environmental clean-up efforts.
Frequently Asked Questions
What is a “janitor fish”?
The janitor fish, known scientifically as plecostomus or suckermouth catfish, is an armored catfish native to South America. This proves often kept in aquariums due to its ability to eat algae but is considered invasive when released into local waterways.
Why are these fish considered harmful to Jakarta?
They are opportunistic omnivores that feed on native species and their eggs, destabilizing the freshwater ecosystem. They damage embankments and riverbanks, which can lead to increased erosion and threaten flood control infrastructure.
How did West Jakarta encourage residents to join the effort?
Mayor Iin Mutmainnah introduced incentives including a payment of Rp 25,000 ($1.50) per kilogram of fish collected, as well as rewards for the most successful teams.
Do you believe financial incentives are an effective way to manage invasive species in urban environments?