This Google Map product indicates the positions of vessels equipped with radio transmitters (generally large ships). Ship positions are determined by a series of receiver stations along the California coast. Each vessel's unique signal allows its name and type as well as speed and direction to be reported on our website. The red balloon marker shows the most recent position of the ship, with the previous trackline indicated by a line extending from marker. The map updates on every hour and at 20 minutes past each hour, showing the location of ships for the nearshore marine area from Pt. Arena to Pt. Conception as of those times. See further instructions below map if needed.

    To use this map:

• Narrow down the ship types shown on the map by clicking one (or more) checkboxes next to ship types at top of page (default is all ship types)
• Click on red map markers do view information on ship of interest
• Or scroll down vessel information column on right and click vessel of interest to be taken to the ship location on the map
• The trackline color corresponds to the type of ship being tracked, defined by the text color of the vessel type in the checkbox menu
• Use map zoom bar to view more or less of the region, and change level of detail for ship tracks
• The National Marine Sanctuary borders are shown in bright green, click within a border to view the sanctuary name.

    AIS data courtesy of the Naval Postgraduate School, Department of Oceanography