Portugal is a maritime nation having the largest exclusive economic zone (EEZ) of Europe. Upon acceptance of the proposal submitted to the United Nations (UN), the Portuguese EEZ will be extended to an area larger than 2 million square kilometres. In addition, Portugal is known as a specialist in maritime matters not only by historical reasons but also due to its contemporary activities on the sea. It is crucial for Portugal to maintain the safety of human life at sea, maintain the safety of its maritime area, and protect the sea and coastline natural environments. The SEAGULL project consists on the use of unmanned air vehicles (UAV’s) as a not only viable but also cheaper solution to help with these difficult tasks on such a large area. The objective is to develop an intelligent system that couples the UAV with sensors like visual, infra-red and hyperspectral cameras along with GPS receivers and other sensors. Its purpose is to fly autonomously over the sea while scanning it to automatically detect, identify, report and follow targets like boats, shipwrecks, lifeboats, boats with suspicious behaviour, and also hydrocarbyls and other chemical pollutants.