Another most impactful projects done by the WCSG is the Island-wide Survey conducted from 2008 to 2015. This significant effort led to the publication of a comprehensive book on Sri Lankan Freshwater Fish after a quarter-century. Notably, the society successfully photographed 91 out of 92 freshwater fish species, showcasing an impressive documentation of the aquatic biodiversity.
Furthermore, the survey resulted in the discovery of two new Rasborides species and four new species of Devario. Also, three species previously considered extinct in the wild were re-recorded, shedding light on their continued existence. This project stands as a milestone in the society’s history, highlighting WCSG’s commitment to biodiversity conservation and its remarkable contributions to understanding and documenting Sri Lanka’s freshwater ecosystems.