This publication presents a full scientific assessment of how a floating LNG terminal could affect the Pagasetic Gulf, a semi enclosed marine ecosystem in Greece. It explains the ecological risks linked to pollution, thermal changes, underwater noise, habitat disturbance, food web disruption, and potential accidents. Using field observations and species monitoring carried out by Merman Conservation, the ebook highlights the vulnerability of local biodiversity, including dolphins, seagrass meadows, fish nurseries, and seabird feeding areas. The goal of this work is to help protect the gulf through informed decision making and to support sustainable environmental policy based on evidence and conservation science.