408 
Fishery Bulletin 109(4) 
in Mexico (Fig. 4, Table 4). Most of the otoliths were 
from late age-0 and age-lfish, except those indicated as 
being from juvenile (all age-0) and adult (>2 years) fish. 
Values close to 50% indicate the collection was close to 
the average of the entire population. Samples in Figure 
4 were aggregated by collection area regardless of date, 
except for two sets: juveniles from region 2 separated 
by collection period, 2003-04 vs. 2010; and region 4 
(San Diego) monthly otolith collections separated into 
2006-07 and 2009-10 sets. 
Length (mm) 
Figure 3 
Pacific sardine (Sardmops sagax) otolith dimen- 
sion relationships for 2213 otoliths from all 
ages and regions: (A) perimeter vs. area; (B) 
perimeter vs. length; and (C) weight vs. length 
relationships with two regression lines shown. 
The power equation best described otoliths <3 
mm in length, and the polynomial equation 
best described larger otoliths. The regression 
equations are described in the text. 
PWPs for Mexican sardine otoliths (regions 5-7) were 
distinct. Otolith weights from the three areas of collec- 
tion were less than the predicted average. Perimeters 
of southern Baja California otoliths from Bahia Mag- 
dalena (pooled from spring and fall samples in 2004) 
and the Gulf of California (pooled from January and 
December, 2006 samples) were markedly lobed. Over- 
all, the PWPs of sardine otoliths from region 6 and 7 
resembled each other in the chi-square tests, unlike the 
results of the MANOVA described in Table 3. Region 5 
otoliths had a PWP weight signature resembling the 
more southern fish and a PWP perimeter signature 
similar to that of southern California sardine. The chi- 
square test of the PWP factors indicated that region 5 
otoliths were different (P= 0.0002) from more southern 
sardine in regions 6 and 7. 
Sardine otoliths from regions 1, 2 (2003-04 collec- 
tion), and 4 resembled each other. These sets included 
both juveniles and adults. By contrast, region 1 and 2 
otoliths were significantly different in the MANOVA 
presented in Table 3. Northern California otoliths (re- 
gions 2\3 and 3) were moderately similar to each other 
(P=0.03). The strongest similarities determined in the 
chi-square tests were between regions 2 and 4, and 
between regions 6 and 7 (P>0.8). 
Correlation coefficients between the residuals (ob- 
served minus average values, ±mm or mg) for each 
Table 4 
Similarities in perimeter-weight profiles (PWPs) in the 
coast-wide survey of Pacific sardine ( Sardinops sagax) 
determined by three-way chi-square tests contrasting 
perimeter based on area, perimeter based on length, and 
weight based on length; n=2213 otoliths. All otoliths were 
age 1-2 except those in collections described as juveniles 
(age-0) and adults (>age-2). Regions are shown in Figure 
1. Region 2, 2003—04 collection; region 3, 1996-97 collec- 
tion; region 4, San Diego collection. Dates of other collec- 
tions are given in Table 1. Where indicated with +, the 
collections were aggregated. 
Contrasted ages and regions 
P 
Region 1: juveniles vs. adults 
0.0351 
Region 2: juveniles vs. adults 
0.3985 
Region 1 vs. 2 
0.1882 
Region 1 adults vs. region 2 adults 
0.0226 
Region 1 vs. 4 
0.2039 
Region 2 vs. 3 
<0.0001 
Region 2 vs. 4 
0.8025 
Region 3 vs. 3\4 
<0.0001 
Region 3 vs. 2\3 
0.0347 
Region 3 + 2\3 vs. regions 6 + 7 
<0.0001 
Region 4 vs. 3\4 
<0.0001 
Region 4 vs. 5 
<0.0001 
Region 5 vs. 6 + 7 
0.0002 
Region 6 vs. 7 
0.8781 
