Table 1 Description of dive metrics calculated for each dive segment
From: Predictive model of sperm whale prey capture attempts from time-depth data
Dive metrics | Definition | Unit |
|---|---|---|
Average depth | Average depth of the segment (m) | m |
Maximum depth | Maximum depth of the segment (m) | m |
Variance depth | Variance in depth over the segment (m) | m |
Depth difference | Difference in absolute depth between the start and end of the segment (m) | m |
Time 60% max. depth | Time spent at > 60% of the maximum dive depth (seconds) | Ratio 0–1 |
Time 70% max. depth | Time spent at > 70% of the maximum dive depth (seconds) | Ratio 0–1 |
Time 80% max. depth | Time spent at > 80% of the maximum dive depth(seconds) | Ratio 0–1 |
Time 90% max. depth | Time spent at > 90% of the maximum dive depth(seconds) | Ratio 0–1 |
Vertical velocity | Difference in absolute depth between time t1 and time t0 | m s-1 |
Average vertical velocity | Vertical velocity averaged over the segment | m s-1 |
Variance vertical velocity | Variance in vertical velocity over the segment | m s-1 |
Vertical acceleration | Absolute difference in vertical velocity between time t1 and time t0 | m s-2 |
Average vertical acceleration | Vertical acceleration averaged over the segment | m s-2 |
Variance vertical acceleration | Variance in vertical acceleration over the segment | m s-2 |
Inflections | Point where Depth(t0)-Depth(t-1) > 0 & Depth(t1)-Depth(t0) < 0 or Depth(t0)-Depth(t-1) < 0 & Depth(t1)-Depth(t0) > 0 | m |
Wiggles | Inflection where depth difference to previous inflection point is > 20 m | 0/1 |
Steady points | Point where Depth(t0) = Depth(t-1) | s |
Sinuosity | Absolute depth difference / Sum vertical velocity over segment | Ratio 0–1 |