Weber and McClatchie: Effect of environmental conditions on the distribution of Scomber /aponicus 
89 
35°N 
30°N 
25°N 
35°N 
30°N 
25°N 
35°N 
30°N 
25°N 
35°N 
30°N 
25°N 
35°N 
30°N 
25°N 
35°N 
30°N 
25°N 
35°N 
30°N 
25°N 
Figure 2 
Corrected densities (number/1000 m 3 ) of Pacific mackerel (Scomber japonicus) larvae captured in oblique tows 
from April through September, 1951-2008 as part of the California Cooperative Oceanic Fisheries Investigations 
(CalCOFI) program. Numbers were corrected for extrusion through the net mesh and net avoidance according 
to Lo et al. (2009). The area enclosed by a black line indicates the core area, which was sampled in all years of 
the survey. The lower black line indicates CalCOFI line 95 separating northern Mexican waters from southern 
Mexican waters near Punta Eugenia. Black “thermometer” bars in lower left corners indicate mean densities rela- 
tive to the maximum density ever measured (1981) in the core area (left bar), northern Mexican waters (middle 
bar), and southern Mexican waters (right bar). 
