Table 1.
Summary of satellite tagged blue whale tracks.
Figure 1.
Blue whale 90% Home Range area (A) and 50% Core Area of Use (B).
Kernel derived Home Ranges and Core Areas of Use were created from blue whale satellite tracks with > = 30 daily locations inside the U.S. Exclusive Economic Zone. Tags were deployed off California from 1998–2008. Data are presented by year on a log scale and the circles inside the boxes are median values.
Figure 2.
Individual overlapping 90% Home Range areas (A) and 50% Core Areas of Use (B).
Kernel derived Home Ranges and Core Areas of Use were created from blue whale satellite tracks with > = 30 daily locations inside the U.S. Exclusive Economic Zone. Shading in the figure represents the number of individual home range and core areas of use that are overlapping in that area. Number of overlapping areas was used as a metric to characterize how much an area was used by the tagged whales. Tags were deployed off California from 1998–2008.
Figure 3.
Relative time spent by satellite tagged blue whales in quarter degree grid cells.
Relative time spent was calculated from satellite-tagged blue whale tracks using weighted locations to account for unequal tracking durations among individuals. Tags were deployed off California from 1998–2008.
Figure 4.
Latitude (Top) and number (Bottom) of blue whale satellite locations plotted by week.
Locations used in the figure were from portions of blue whale satellite tracks that occurred within the U.S. Exclusive Economic Zone waters. The red line indicates the median value.
Figure 5.
Julian day of U.S. Exclusive Economic Zone departure by satellite tagged blue whales.
Circles in the boxes are median values.
Figure 6.
One whale was tracked for 504-year comparisons of space use.
Locations within the U.S. Exclusive Economic Zone were recorded from 20 August to 12 November in both 2004 and 2005 for one whale. 90% Home Range (A) and 50% Core Areas of Use (B) were created from the locations to characterize the areas used by the whale in 2004 (blue) and 2005 (transparent yellow to better see overlap). The full summer tracks from 2004 and 2005 are included in the first image for reference.
Figure 7.
Number of overlapping blue whale Core Areas of Use near commercial shipping lanes.
The Core Areas of Use were created from blue whale satellite tracks with > = 30 daily locations inside the U.S. Exclusive Economic Zone. The regions shown are the Channel Islands (A) and the Gulf of the Farallones (B). Tags were deployed off California from 1998–2008. Hashed polygons represent the commercial shipping lanes transiting the area. Inset histograms show the overall number of blue whale locations recorded in the U.S. Exclusive Economic Zone (gray), and the number of locations recorded in the area shown (black).