This website makes heavy use of google earth plugins to display tracking and other data. This technology may not be supported on mobile phones, pads or tablets.   


About Satellite Tag Tracks

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Species/Country Results

How is the data generated?

For Researchers

When an IGMR tag pops up, either because it has released prematurely or because it has reached the end of its programmed deployment period, it begins transmitting a summary of its stored data through the Argos satellite system. The location of the tag when it begins transmitting is measured very precisely (within about a 50 m radius), and is used to determine the winner of each race. Each tag transmits data until it exhausts its battery – typically about 7-10 days after it reaches the surface.

Once all the data are received from a tag, a series of plots are generated to visualize temperature and depth preferences, diving behavior, and water column conditions. Researchers at Stanford University also use the light-based geo-location data from the tag to construct an initial track for the animal. This is accomplished by using sunrise/sunset data to estimate longitude, combined with satellite-derived sea surface temperature data to estimate latitude. This track is further refined using a state-space model, which uses a sophisticated algorithm to draw a statistically robust, “best fit” track through the light-based geo-location points. This final track is finally processed to create the interactive, Google Earth views you see on this website.

Learn more about the science behind the IGFA Great Marlin Race on our About page.