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Importing BAS/Biotrack solar geolocator data

From your study, select Upload data > Import data > Processed solar geolocator data > BAS trajectory data. This upload channel accepts .trj files output by the BirdTracker software used to process data from archival solar (light-level) geolocators developed by the British Antarctic Survey (BAS) and Biotrack*. It also accepts other comma-delimited files with the same format. If you have changed the format of BirdTracker output data, you should select Import data > Other location data and follow the instructions for uploading custom data. For more information on .trj files please see the BAS user manual.

To complete the upload, you will only need to define the animal and/or tag associated with the data file.

Currently, Movebank maps the BirdTracker attribute "stationary latitude" to the Movebank Latitude (decimal degree) attribute. In addition, Movebank imports both the stationary and compensated latitudes calculated by BirdTracker as separate attributes. If you are interested in a more dynamic method of assigning these two latitude estimates to the Movebank Latitude (decimal degree) attribute, and would be willing to work with us to define such a method, please contact us at

We recognize that in the case of solar geolocators, location estimates can vary widely, depending on the processing methods used, and thus the raw light-level data can be as or more important than the derived location estimates. We are working on building support for the storage and documentation of raw light-level files. If you work with light-level geolocator data and want to provide comments about how such a feature could be most helpful to you, please contact us at

*The solar geolocators designed and developed by the British Antarctic Survey are now under license to the company Biotrack. As of December 2011, we know of no differences in data collection or file formats due to this change.