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Table 3 Characteristics of two activity modes observed for Pacific halibut (Hippoglossus stenolepis) in Port Frederick, Alaska

From: Characterizing activity and assessing bycatch survival of Pacific halibut with accelerometer Pop-up Satellite Archival Tags

  Fish PF-1 Fish PF-2 Fish PF-3
Hopping
Median KDs (range) 5.5 (0–21) 3 (0–12)*** 3 (1–18)***
Median %tilt (range) 5.0 (0.6–25.8)*** 2.5 (0.2–14.8)*** 2.3 (0.3–29.6)***
Median ratio KDs: movement events (range) 1 (0–3)** 0.9 (0–2.5)*** 1.1 (1–3)***
Median SD Depth (m) per hour (range) 1.2 (0.1–6.7) ** 0.9 (0.3–4.3)*** 0.8 (0.3–5.1)***
% Movement events with change in depth 79 84 74
Sustained swimming
Median KDs (range) 4 (1–16) 12.5 (0–20) 21.5 (4–48)
Median %tilt (range) 12.3 (3.7–70.2) 47.2 (3.8–76.1) 47.9 (9.9–91.5)
Median ratio KDs: movement events (range) 2 (0.8–11) 2.4 (0–6) 2.8 (1.2–12)
Median SD Depth (m) per hour (range) 2.5 (0.7–10.2) 3.4 (1.0–7.7) 4.9 (0.7–9.5)
% Movement events with change in depth 88 100 89
  1. Hourly characteristics of the hopping and sustained swimming activity modes observed for Pacific halibut (Hippoglossus stenolepis) tagged with accelerometer Pop-up Satellite Archival Tags in Port Frederick (PF), Alaska, as determined from acceleration data, including: median and range number of tag knockdowns (KDs, count of abrupt changes in tilt), %tilt (proportion of time spent active), ratio of KDs to number of visually identified movement events per hour, standard deviation of depths, and percent of overall movement events that were accompanied by a detectable (> 0.5 m) change in depth. Asterisks denote significant difference between movement states for individual fish (Wilcoxon rank-sum tests), where *p < 0.05, **p < 0.01, and ***p < 0.001