Alien fish invading Pakistani waters, endangering native biodiversity

WWF-Pakistan has warned that an alien fish species has been sighted in Sindh and Lower Punjab, thereby threatening biodiversity as well as the economy based on fish resources.

The environmental group stated in a statement that an unusual fish was also observed to be brought to the Karachi Fish Harbor on January 4 from the nearby dhand in Sukkur, which was declared as an “alien species,” since no one could identify the fish.

Later, it was identified as an Amazon Sailfin Catfish. According to the information, a kind of fish that has a thick and armored body and is covered with bone-like structures is an exotic species of fish that entered water resources accidentally or deliberately and is found in the province of Sindh and Lower Punjab.

Amazon sailfin catfish is native to Latin America and is widely popular as an aquarium fish in the world. It is a highly successful invading species, and since the species is now wide-spread in Pakistan, its eradication and control is impossible,” the statement read.

The organization said that this species is included among the 26 invasive fish species that have been accidentally or intentionally introduced into Pakistan, have become invasive, are causing a pernicious impact on the aquatic biodiversity of Pakistan, and have threatened the sensitive balance and functioning of the ecosystem.

Invasive fish species can causally affect aquatic biodiversity by competing with the existing fish species for food and space, preying on them, transferring fish diseases, and modifying habitats; this not only causes the extinction of fish species but can lead to the depletion of the fishery resource in terms of reduced fishing revenue, according to WWF-Pakistan.

According to the report, the spread of invasive species is also regarded as “a serious threat to the sensitive aquatic ecosystem in natural water bodies like rivers, streams, and lakes in Pakistan.”