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Table 2 Indices for each species-size category and FAD array

From: Effects of habitat modifications on the movement behavior of animals: the case study of Fish Aggregating Devices (FADs) and tropical tunas

  YFT-70 YFT-50 SKJ-50
Mauritius Hawaii Mauritius Hawaii Maldives Mauritius Maldives
Ntuna 14 56 11 9 19 15 22
CRT (days) 7.8 (8.8) 5.7 (11) 15 (15) 5.8 (7.5) 2.5 (4.4) 2.5 (4.4) 1.4 (2.6)
CATreturn (days) 2.6 (2.9) 9.8 (22) 1.7 (0.53) 3.9 (3.6) 3.0 (2.6)
CATdiff (days) 0.79 (0.98) 3.9 (6.7) 0.64 (0.11) 11 (15) 2.8 (8.9)
NCRT 3.2 (2.5) 2.1 (2.3) 1.5 (0.52) 1.7 (0.87) 1 (0) 2.9 (2.2) 1 (0)
NCATreturn 0.77 (1.0) 0.48 (1.1) 0.40 (0.70) 0.11 (0.33) 0 (0) 0.87 (1.5) 0 (0)
NCATdiff 1.5 (1.9) 0.7 (2.1) 0.20 (0.42) 0.67 (1.1) 0 (0) 1.1 (1.3) 0 (0)
  1. Mean values (standard deviation). Number of tuna (Ntuna), number and mean duration (in days) per individual for each species-size category and FAD array. A CRT corresponds to the residence time at one FAD, a CATdiff corresponds to the time between two consecutives visits at two different FADs and a CATreturn corresponds to the time between two visits to the same FAD with an absence longer than 24 h. The mean number of CRTs, CATreturn and CATdiff were calculated for the first 38 days of tracking of each tuna, while the mean duration of CRT, CATreturn and CATdiff were calculated over the entire observation time. The inter-FAD distances increase in order of Mauritius-Hawaii-Maldives