Pathways and booster of Pterygoplichthys pardalis invasion in the East Kolkata Wetlands, India and their impacts on native fish population or community, and ecosystem. (A) Sewage distribution canals- the major pathway of P. pardalis spread and entry to the water bodies, (B) dense Eichhornia crassipes mats (spread: 2–3 m) along the periphery of the water bodies- use by the species as shelter in weak stages (young / mature fishes) or as hide-outs, (C) abundance of plankton population including detritus in EKW water bodies- the principal food of P. pardalis, (D) self-sustaining breeding population of P. pardalis in EKW.