The Invasive Amazon Sailfin Catfish (Pterygoplichthys spp.) as a Potential Biomonitor of Polluted River Ecosystems in Malaysia: An Ecotoxicological Reflection

Abstract

Biomonitoring is a fundamental component of ecotoxicology, providing insights into environmental quality through the responses of living organisms to pollution and habitat degradation. Traditionally, biomonitoring programmes have focused on species that accumulate contaminants or exhibit measurable physiological responses to environmental stress. In Malaysia, the invasive Amazon sailfin catfish (Pterygoplichthys spp.), commonly known as ikan bandaraya, has become widespread in urban and disturbed freshwater ecosystems. While the species is generally regarded as an invasive alien fish threatening native biodiversity, its ecological distribution may also provide valuable information regarding environmental quality. This reflection paper proposes a novel ecotoxicological perspective in which Pterygoplichthys spp. may function as a biomonitor of degraded river ecosystems. The concept emerged from field observations, student reflections noting that the species appears to thrive in polluted waters, and public statements by Prof. Mohammad Noor Noor Amal indicating that increasing populations of ikan bandaraya may reflect deteriorating river conditions. By integrating invasion ecology, freshwater biomonitoring principles, and published studies from Malaysia, this paper explores the potential use of Pterygoplichthys occurrence, abundance, and population dominance as indicators of ecosystem disturbance. The paper argues that while the species remains an invasive organism requiring management attention, its ecological success may simultaneously provide valuable information regarding pollution, habitat modification, and declining ecosystem health. This perspective broadens the traditional scope of ecotoxicological biomonitoring and highlights the potential role of invasive species as indicators of environmental degradation in tropical freshwater ecosystems.

Keywords: Biomonitoring; Ecotoxicology; Invasive Species; Pterygoplichthys; Freshwater Pollution; River Ecosystem Health

Citation

Kong Yap C, Noor Amal Azmai M, Anak Chengai Z, Amirul Faiz Zulkiply M, Hezrey Eldridge H, Muhamad Daniel Sayed Shamsul Effendi S. The Invasive Amazon Sailfin Catfish (Pterygoplichthys spp.) as a Potential Biomonitor of Polluted River Ecosystems in Malaysia: An Ecotoxicological Reflection. WebLog J Environ Sci. wjets.2026.h1203. https://doi.org/10.5281/zenodo.22168094