We identified glides as segments where the absolute value of the

We identified glides as segments where the absolute value of the Hilbert transform of the pitch rate signal was <0.05 (Woodward

et al. 2006a), and visually checked these sequences. Based on previously described gliding behaviors in right whales (Nowacek et al. 2001, Woodward et al. 2006a), we defined the minimum glide duration as 5 s. Following Wilson et al. (2006) find more and Fahlman et al. (2008), we calculated Overall Dynamic Body Acceleration (ODBA, g) by smoothing accelerometer measurements in three separate axes, with a window size of 3 s. We then subtracted these smoothed data (static acceleration) from the unsmoothed data to estimate the dynamic acceleration in each axis. Finally, we then calculated ODBA as the sum of the absolute value of dynamic acceleration in each axis. We observed peaks and identified outliers in ODBA at each surfacing event, and therefore

calculated mean ODBA values within dives, between dives, and during descent and ascent periods of each dive. We defined three phases of the sedation and disentanglement of Eg 3911 (Table 2) hereafter referred to as (1) Sedation/Entangled: animal towing gear and attached buoys, and sedative injection; (2) Disentangled: following removal of most of trailing gear and buoys, administration of antibiotics, and attachment of the satellite LIMPET tag (Andrews et al. 2008); and (3) Recovery: retrieval of injection darts, this website dart tethers and floats (Moore et al. 2010), and the end of active boat approaches. To determine the behavioral effects of sedation on an entangled whale, we used Wilcoxon rank sum

tests to compare dive parameters and respiration rates within the Sedation/Entangled phase, between the 21 min prior to and the 50 min following sedative injection, but prior to removal of the gear and buoys. We used Three-sample Kruskal-Wallis single factor analysis of variance tests with tied ranks and post hoc Bonferroni-corrected (α =  0.05/3 = 0.0167) Wilcoxon rank sum tests to compare the distributions of various dive click here parameters between Sedation/Entangled, Disentangled and Recovery phases. To compare the observed vs. expected ratio of time spent above and below the wave drag limit between phases, we used Chi-square contingency tables. We compared fluke stroke rate, RMS, and the frequency and duration of glides across phases within the single tag deployment to infer changes in thrust intensity and power requirements. As propulsive (thrusting) forces should equal resistive forces (net buoyancy and drag), we expect thrusting intensity (stroke rate and RMS) to be greater and for fewer and shorter glides to occur in entangled vs. nonentangled conditions.

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