Map of the study area displaying one daily position estimate of each tagged whale.

<p>All eight whales were tagged within the Southern California Anti-submarine Warfare Range (outlined in solid white). Tagged whales were within the San Nicolas Basin for 51% of all days tags transmitted, and within the SOAR boundaries for 71% of the days when in the basin, suggesting site fidelity to the MFA sonar training range. Inset map shows the entire track-line of each tagged whale with the primary map region indicated by a dashed box. The SOCAL Range Complex, which encompasses all areas of authorized MFA sonar use <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092633#pone.0092633-Anonymous1" target="_blank">[6]</a>, is lightly shaded and outlined in black in the inset map. Map created using Mysticetus Observation System, v1.8.0.124 (Entiat River Technologies, Preston, WA, USA).</p

Diel differences in diving behavior.

<p>Behavior modes were partitioned into day and night classes for each tagged whale, and the total time spent within each class was calculated for each whale by day and night. A series of paired T-tests was then run (<i>df</i> = 7 for all tests) to assess diel differences. In general, whales spent more time at the surface at night and more time on shallow dives during the day. Though they conducted significantly more deep dives at night, the total time spent deep diving was not significantly different, as night time deep dives were often shorter in duration.</p

Variation in diving behavior.

<p>(<b>A</b>) A 48-hr BL dive trace from Zc015, illustrating the pattern of “deep” and “shallow” dives. Darkened areas represent night. The gap in the dive record during the first night period reflects data that were not received via Argos. (<b>B</b>) Box plot of deep dive duration by day for the first 26 days of Zc015. The dashed line represents the overall median dive duration for Zc015 of 64.0 min. (<b>C</b>) Histogram plot of “deep” dive duration by individual, demonstrating the variability both within and among individuals. The solid black line connects the median value for each individual; the dashed lines connect the upper and lower 25th percentiles.</p

Inter-deep dive intervals (IDDI) and deep dive rates.

<p>Individual table values are medians, with ranges in parentheses. The IDDI represents the period from the end of one deep dive to the beginning of the next deep dive, where there was no gap in dive data. Datasets are summed and group means (s.d.) are calculated across individuals at the bottom of the table.</p

Summary of dive and surfacing bout parameters by individual.

<p>Individual table values are medians, with ranges in parentheses. * indicates tags that logged the start and end of dives and surfacing bouts when the whale passed through 5 m depth on descent/ascent of qualifying dives; others used the wet/dry sensor on the tag for time stamps. The latter likely represent a more accurate measure of actual respiratory periods in surfacing bout metrics. Datasets are summed and group means (s.d.) are calculated across individuals at the bottom of the table.</p

Box plot of surfacing bout duration by surfacing type, by individual.

<p>First Surfacing bouts (FS), Intermediate Surfacing bouts (IS), Terminal surfacing bouts (TS), and Single Surfacing bouts between deep dives (SS). Only the five tags using the wet/dry sensor are included (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092633#pone-0092633-t002" target="_blank">Table 2</a>). Zc019 had only one SS, and Zc017 did not conduct any consecutive deep dives. Boxes represent the median and inter-quartile range, with whiskers at 1.5 times the inter-quartile range. Severe outliers are indicated by plus symbols. Surfacing bouts were typically very short, however occasional severe outliers (representing unusually long surfacing bouts) occurred in all surfacing bout types.</p

Summary of satellite tag deployments by individual.

<p>Summary of satellite tag deployments by individual.</p

Distance to deployment location from day of deployment, by individual.

<p>Distance from deployment was calculated using the best location per day, as determined by the Douglas Argos Filter <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092633#pone.0092633-Douglas1" target="_blank">[14]</a>. All individuals were tagged on the SOAR MFA sonar training range, and most remained in close proximity to the area in which they were tagged. While Zc015 made an extra-regional excursion over 450 km away, she returned to within 5 km of her tagging location.</p

Number of biopsy sampling and satellite tagging attempts on killer whales at Marion Island.

<p>Notes: ^aFollowing <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0111835#pone.0111835-Best1" target="_blank">[24]</a>; ^bHit and tissue sample for biopsy sampling, hit and attach for satellite tagging; ^cTags attached, but did not necessarily penetrate properly.</p><p>Number of biopsy sampling and satellite tagging attempts on killer whales at Marion Island.</p

Description of scores used to assess the immediate reactions of killer whales to biopsy sampling or tagging.

<p>Description of scores used to assess the immediate reactions of killer whales to biopsy sampling or tagging.</p