In early 90s of last century when the Ministry of Environment and Forests were busy framing policy, laws, projects and committees for identification and conservation of Wetlands of India, this author had the opportunity to attend some of the meetings on preparing projects along with Bose Institute, Salim Ali Center for Ornithology and natural history and other experts. He founds almost all the members were simply ignorant of the monumental work done on Aquatic ecology by the Central Fisheries, this was also further exposed as no fishery experts were made a committee member. This author took over the task of preparing a treatise on Wetland Ecology, and resources and published a book in 1998, the title of which was “Wetland Ecology: Research, Resources and Conservation”. The present work has the foundation in that work, but many recent works have been added as enrichment. The author has pointed it out that the subject has not received proper attention in India. The precarious land use situation, human settlement, poaching, encroachment, over exploitation, pollution and many other causes have resulted in eradication of wetlands from this country. All chapters have put up salient features of wetland supported by adequate research data. Most of the chapters present research findings of various scientists. The role and importance of fish in wetland had been elaborately discussed.