ERROR WARNING:
No GRTS Cell in this sample frame at this latitude and longitude
HOW TO RESOLVE:
Ensure each row has a valid location combination: 'GRTS Cell Id' alone, 'GRTS Cell Id' with 'Quadrant', or 'Latitude'/'Longitude'. Verify longitudes are negative and lat/long values aren't swapped. If both GRTS ID and coordinates are present but conflict, remove whichever you trust less—delete the 'GRTS Cell Id' value (keeping the column) if you trust coordinates, or omit lat/long to let the system match on 'GRTS Cell Id' and 'Site Name'. Ensure site names are unique to prevent ambiguity. For repeat visits to established sites, verify coordinates remain consistent—new coordinates within 55m of an existing site are ignored, coordinates 55–100m away create a new map point but maintain site association, but coordinates exceeding 100m generate an entirely new site record, breaking data continuity and preventing trend analyses. Mobile transect surveys operate under different logic that matches primarily on unique 'Site Name' values; see "ADDED EXPLANATION" for details.
ADDED EXPLANATION:
NABat requires at least a 'GRTS Cell Id' to assign surveys to a 10×10 km grid cell, but recommends providing additional granularity via 'Quadrant' or 'Latitude'/'Longitude'. Location errors occur when this information is missing, ambiguous, or internally conflicting. Ambiguity commonly arises when generic site names (e.g., "Bridge 1" or "Cave") are reused across multiple locations, or when provided coordinates fall outside the boundaries of the stated GRTS cell. For large datasets, load coordinates into GIS or mapping tools to verify placements and catch systematic issues such as swapped lat/long columns or missing negative signs. To avoid unintentional site splits when revisiting established sites, verify coordinates match prior uploads or omit coordinates entirely to let the system match on Site Name alone.
Mobile transect surveys can match solely on a unique 'Site Name' value, bypassing some ambiguity checks applied to other survey types. It is recommended that users draw a line object representing their route on the project map, named to exactly match the Site Name value(s) in the upload file. The portal can then estimate missing lat/long coordinates by combining route geometry with elapsed time during the survey. Without a defined line object, surveys traversing multiple GRTS cells with missing coordinates cannot be processed—users must estimate coordinates themselves or provide the 'GRTS Cell Id' for each record. Surveys occurring entirely within a single cell should still have their route drawn; however, users preferring coarser resolution can provide only the 'GRTS Cell Id'.