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Table 2 Results of models used to examine relationships between walleye pollock abundance and northern fur seal behavior

From: Linking northern fur seal behavior with prey distributions: the impact of temporal mismatch between predator studies and prey surveys

  Pollock catch per effort (WTCPUE/NUMCUPE)
2 weeks 1 month Full
Hours in grid/area (h/km2) NS NS NS/P = 0.02
Transit rate (km/h) NS NS NS
Dives/grid hour (count/h) P = 0.04/P = 0.04 NS NS
Dives/grid area (count/km2) P = 0.03/P = 0.02 NS NS
Vertical distance/grid hour (m/h) P = 0.01/P = 0.01 P < 0.001/P < 0.001 P = 0.03/P = 0.005
Vertical distance/grid area (m/km2) P = 0.04/P = 0.04 P = 0.003/P = 0.003 P = 0.03/NS
Bottom time/grid hour (min/h) NS NS NS
Bottom time/grid area (min/km2) NS NS P = 0.04/NS
Percent bottom time NS NS NS
Dive time/grid hour (min/h) P = 0.02/P = 0.03 P = 0.03/P = 0.03 NS/ P = 0.02
Dive time/grid area (min/km2) NS/P = 0.04 P = 0.03/P = 0.04 NS
Descent rate (m/s) NS P = 0.001/P = 0.001 P = 0.03/P = 0.009
Ascent rate (m/s) NS P < 0.001/P < 0.001 P = 0.002/P < 0.001
Wiggles/dive NS P = 0.002/P = 0.002 P = 0.04/P = 0.02
Wiggles/grid hour (count/h) NS P = 0.01/NS NS
Wiggles/grid area (count/km2) NS P = 0.003/NS P = 0.04/NS
  1. Behavior metrics were investigated at three temporal scales: within 2 weeks of the prey survey (2 weeks), within 1 month, and over the fur seal reproductive period (full, approximately 4 months). Pollock abundance was measured as catch per unit effort calculated as kilogram per hectare (WTCPUE) and number per hectare (NUMPUE). All behavior metrics that were significant were positively correlated with prey abundance, except hours per grid area. Behavioral variables that were not significant are denoted by NS.