The Coast Guard is the maritime service that makes boating safer for everyone and acts as a steward of the marine environment. Coast Guard search and rescue operations locate people in danger and return them to safety. The Coast Guard protects marine ecosystems, fisheries, and endangered species. The Coast Guard prepares for and responds to marine pollution, from beach clean-ups to oil spills. The Coast Guard acts as a waterway manager and operates the national Marine Transportation System to support access to navigable waterways for mariners. The Coast Guard is a disaster response agency that works to mitigate and respond to weather emergencies (such as hurricanes and floods) and mass casualties. It conducts emergency management, evacuation, and rescue as well providing humanitarian assistance in the US and to other nations.