Fig. 2

Examples of differences in GPE3 track reconstructions between partial data sets (from transmitted data, yellow) and complete data sets (physically downloaded from tags, blue) for two tags (one per row), one that completed a full deployment and one that released prematurely. Maps show the 99% likelihood surfaces and reconstructed locations for the same tag. Columns show the resultant track if only 5%, 10%, 20%, 30% or 40% of the data are received in comparison with the complete data set. Scatterplots show spatial similarity (τ) between partial and complete data sets for all sampled fish for short range (top row), and long-range (bottom row) groups. Corresponding spatial similarity values are also stated on each map. For long-range tags that entered the Mediterranean Sea, the orange vertical line represents the minimum data volume at which ABT (all individuals pooled) were first placed in the region. “EC”—“the Channel” and “BoB”—Bay of Biscay