Tidal power can have effects on marine life. The turbines can accidentally kill swimming sea life with the rotating blades, although projects such as the one in Strangford feature a safety mechanism that turns off the turbine when marine animals approach. However, this feature causes a major loss in energy because of the amount of marine life that passes through the turbines. Some fish may no longer utilize the area if threatened with a constant rotating or noise-making object. Marine life is a huge factor when placing tidal power energy generators in the water and precautions are made to ensure that as many marine animals as possible will not be affected by it. The Tethys database provides access to scientific literature and general information on the potential environmental effects of tidal energy. In terms of Global Warming Potential (i.e. carbon footprint), the impact of tidal power generation technologies ranges between 15 and 37 gCO2-eq/kWhe, with a median value of 23.8 gCO2-eq/kWhe. This is in-line with the impact of other renewables like wind and solar power, and significantly better than fossil-based technologies.