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Table 3 Median values (M) of untransformed kinematic dive variables (interquartile ranges, IQR, shown in parentheses) by dive type, recorded for 30 northern resident killer whales carrying Dtags (31 deployments)

From: Fine-scale foraging movements by fish-eating killer whales (Orcinus orca) relate to the vertical distributions and escape responses of salmonid prey (Oncorhynchus spp.)

Dive variable Foraging training set Foraging dives Respiration dives Other dives Coefficients of linear discriminant
N = 15 N = 701 N = 7050 N = 3568
Dive duration (min) 3.68 (2.35) 2.94 (2.36) 0.33 (0.27) 0.34 (0.29) −1.7075
Maximum dive depth (m) 133.67 (61.57) 34.00 (71.02) 2.75 (1.34) 3.15 (1.92) 0.2537
2D dive straightness index 0.86 (0.26) 0.95 (0.12) 1.00 (0.004) 0.97 (0.05) −0.1045
3D descent straightness index 0.81 (0.16) 0.94 (0.12) 0.99 (0.02) 0.93 (0.10) −0.1066
3D ascent straightness index 0.90 (0.09) 0.93 (0.11) 0.99 (0.02) 0.93 (0.07) 0.0362
Mean VeDBA 0.17 (0.06) 0.10 (0.07) 0.09 (0.05) 0.11 (0.08) 0.1421
Maximum absolute roll (deg) 179.84 (0.15) 132.32 (128.43) 14.12 (20.72) 28.75 (32.24) −0.1204
Mean absolute roll (deg) 65.92 (29.17) 21.58 (41.32) 5.50 (7.12) 9.71 (10.55) −0.0770
Overall swim speed (m s−1) 2.72 (0.45) 2.08 (1.12) 1.91 (0.90) 1.17 (0.75) 0.0801
Descent : ascent duration 1.41 (1.31) 0.85 (0.95) 1.05 (0.53) 1.03 (0.61) −5.1212
Vertical descent velocity (m s−1) 0.98 (0.72) 0.66 (0.66) 0.29 (0.15) 0.32 (0.17) −5.9038
Vertical ascent velocity (m s−1) 1.93 (1.02) 0.57 (0.76) 0.30 (0.16) 0.33 (0.20) 4.9175
Descent Δroll/time (deg s−1) 27.08 (13.47) 8.56 (13.57) 4.93 (5.40) 7.34 (6.85) 0.1164
Ascent Δroll/time (deg s−1) 43.52 (26.17) 9.70 (12.55) 4.11 (4.18) 6.45 (5.69) 0.1094
Descent Δpointing angle/time (deg s−1) 57.36 (22.44) 22.62 (29.98) 21.50 (20.53) 26.35 (34.65) 0.0352
Ascent Δpointing angle/time (deg s−1) 51.64 (23.02) 22.05 (21.65) 11.24 (8.52) 15.37 (12.48) −0.2077
  1. Coefficients of the linear discriminant indicate weights applied to each dive variable, with larger absolute values indicating variables that provided greater separation between the foraging and non-foraging dive types