Sanchez-Rubio and Perry: Meteorological and hydrological regimes and their influence on recruitment of Brevoortia patronus 
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Warm Neutral Cold 
Figure 3 
Box plots of (A) abundance of early juveniles of men- 
haden species in seine surveys, measured as numbers 
per haul, in the western region of the Gulf Coast and 
Palmer Drought Severity Index (PSDI) in the (B) cen- 
tral and (C) western regions during the period 1985- 
2008 under interannual hydrological events associated 
with the El Nino Southern Oscillation (ENSO). Hori- 
zontal lines for each box plot indicate the 5th, 25th, 
50th (median), 75th, and 95th percentiles. Outliers are 
shown as dots, and they are labeled by year. 
root-transformed N:P ratio of Mississippi River influx 
and north-south wind direction. Correlation analysis of 
BPL catches with the actual environmental variables 
showed that catches in the BPL hauls were correlated 
with the cube-root-transformed Mississippi River N:P 
ratio (r=0.670, PcO.OOl). Although numbers of early ju- 
veniles in seine hauls were not related to any of the 
extracted components, abundances of early juveniles 
in seine hauls in the western region were correlated 
with cube-root-transformed Mississippi River N:P ra- 
tio (r=0.591, P=0.002). These results indicate that high 
(3.6/BPL haul) abundances of age-0 Gulf menhaden 
from BPL hauls in the central region and high (38.3/ 
seine haul) abundances of age-0 menhaden species 
from seine hauls in the western region were found 
during periods of a high (2.3) N:P ratio of Mississippi 
River influx. 
Multiple regression analyses were performed be- 
tween abundance of Gulf menhaden from fishery-inde- 
pendent BPL surveys and the 5 extracted components. 
According to the regression models developed from AIC, 
2 significant predictors (third and fifth components) 
with negative and positive regression coefficients, re- 
spectively, explained 60% of the variance contained in 
cube-root-transformed BPL catches of early juvenile 
Gulf menhaden (Table 3, Fig. 4A). These results indi- 
cate that the variability in abundance of age-0 Gulf 
menhaden was partially explained by climate-relat- 
ed meteorological and hydrological conditions in the 
northern GOM. 
Analyses of fishery-dependent data Mean ranks of com- 
mercial harvest (numbers and proportions of age-1 Gulf 
menhaden; % 2 >7.340, P<0.026) and climate-related hy- 
drological parameters (precipitation, PDSI, river flow, 
and sea level in the central region and sea level in the 
western region; % 2 >6.041, P<0.05) were different among 
the coupling of AMO and NAO phases. Proportions of 
age-1 Gulf menhaden in landings (Z= -2.982, P=0.003; 
Fig. 5A), PDSI (Z= -2.429, P=0.015; Fig. 5B), and river 
flow (Z= -2.595, P=0.009; Fig. 5C) in the central region 
were higher during the decadal wet regime than during 
the decadal dry regime. Numbers (Z= -2.673, P=0.008; 
Fig. 6A) and proportions (Z= -3.274, P=0.001; Fig. 
5A) of age-1 fish in landings were higher during the 
decadal average regime than during the dry regime, 
but sea level (Z< -2.672, P<0.009) in the western (Fig. 
6B) and central (Fig. 6C) regions was lower during the 
decadal average regime than during the dry regime. 
Principal component analysis revealed 3 components 
of climate-related meteorological and hydrological pa- 
rameters associated with Gulf menhaden commercial 
landings (Table 4). Correlation analysis of commercial 
landings with the 3 extracted principal components 
showed that landings of age-1 Gulf menhaden were 
correlated with 1 of the 3 extracted components. Num- 
bers (r= -0.689, P=0.000) and proportions (r= -0.571, 
P=0.000) of age-1 Gulf menhaden were correlated with 
the second component. In order of importance, the vari- 
ables loaded on the second extracted component were 
