Pakistan’s freshwater ecosystems are facing a serious threat due to the rapid spread of an alien fish species known as the Amazon sailfin catfish. Originally native to Latin America, this fish has now invaded rivers, canals, and lakes across Pakistan, raising strong concerns among environmental experts.
The Amazon sailfin catfish is easy to identify. Its body is covered with hard, bony plates and has a thick, armoured structure. It is widely sold as an aquarium fish around the world. However, once released into natural waters, it becomes highly aggressive and difficult to control. Experts say the species has spread so widely in Pakistan that complete removal or effective control is no longer possible.
This catfish feeds heavily on algae and bottom-dwelling organisms, which disrupts the natural food chain. As a result, native fish species struggle to survive. The invasive catfish also damages riverbeds and breeding grounds, further harming local aquatic life.
The sailfin catfish is not the only invasive species in Pakistan. At least 26 alien fish species have been introduced into the country over time, either intentionally for farming and sport or accidentally through aquariums. Many of these species later became invasive and caused long-term damage to freshwater ecosystems.
According to WWF Pakistan, there is no doubt that alien fish species have negatively affected aquatic ecosystems across the country. Conservationists warn that urgent awareness, strict regulation, and better management are needed to protect Pakistan’s rivers and native fish before more irreversible damage is done.