When viewed from the shore the ocean may seem like a boundless resource with plenty of space, but the reality is quite different.  Coastal areas are home to shipping lanes used by commercial vessels, attractive fish habitat that supports commercial and recreational fisheries,  underground utility cables connecting people with essential services, and a variety of animals that fly and swim.  In the midst of all this activity MarineCadastre.Gov was born.  Originally designed to provide technical support for renewable energy siting in the ocean, MarineCadastre.Gov now serves up a wealth of data used to inform ocean and Great Lakes planning.  A variety of federal agencies act as data providers for MarineCadastre.Gov, including science, regulatory, and law enforcement offices.  Users can find pre-made maps on topics such as renewable energy, offshore shipwrecks, and fishing vessel density, or they can make custom maps with the free online map viewer.  Many of the maritime datasets used to make online maps through MarineCadastre.Gov are also available for free download through Data.Gov, including datasets related to marine transportation such as:

2013 Tanker Vessel Density from Department of Commerce: https://catalog.data.gov/dataset/2013-tanker-vessel-density

Offshore Wind Resources from the Department of Energy: https://catalog.data.gov/dataset/offshore-wind-resource-10517

BOEM Wind Planning Areas from the Bureau of Ocean Energy Management, Department of the Interior: https://catalog.data.gov/dataset/boem-wind-planning-areas