Final Technical Report: - Southwest Fisheries Science Center - NOAA

0.29 (Risso’s dolphin) to 3.20 (northern right whale dolphin). The seemingly poor
performance of the northern right whale dolphin models was due in part to the small
number of sightings (5) available for model validation. The contour plot of the 2005
density predictions from the 1991-2001 models shows that the model did capture the
general distribution pattern for this species (Fig. 25).
Figure 24. Predicted relative density estimates for Dall’s porpoise (top) and northern right whale dolphin
(bottom): (A) summer predictions based on the summer shipboard models and (B) winter predictions based
on the summer shipboard models. Colors reflect relative density, where white represents the range of
lowest density. Density estimates for each segment were interpolated on a grid resolution of approximately
12 km using inverse distance weighting to the second power (Surfer Version. 8 software). Red dots show
sighting locations from the summer shipboard (A) and winter aerial (B) surveys.
In contrast, the inability of the Risso’s dolphin models to effectively predict
distribution patterns for the novel year is clearly reflected in the 2005 predicted density
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