Widespread loss of the Mediterranean’s dominant seagrass species, Posidonia oceanica, have been documented over the past two decades and are expected to increase under imminent aquaculture expansion plans. This study aims to investigate historic and current impacts of fish farming on P. oceanica meadows around the island of Poros, Greece, aiming to quantify the magnitude, spatial extent, and persistence of potential health declines, to establish baseline conditions for future monitoring and to anticipate future impacts. By Emily Jones. Supervised by Dr. Gwilym Rowlands, Dr. Nancy Burrell & Dr. Katrina Davis.