Rincon et al.: A Bayesian model with duai-time resolution for estimating abundance of Engraulis encrasicolus 
47 
Figure 5 
Kullback-Leibler divergence between the modeled and real length-frequency distributions of 
the population of European anchovy (Engraulis encrasicolus) in the Gulf of Cadiz, Spain, dur¬ 
ing 1988-2004 grouped into 6 length classes of 2 cm each from 10 cm to 22 cm total length. 
improves coherence between model output and field ob¬ 
servations throughout the life cycle of this fish, includ¬ 
ing independent observations that represent a genuine 
validation of the approach (Pauly et ah, 2013). Envi¬ 
ronment clearly influences future recruitment of this 
species very early in life. For management purposes 
this fact implies that the concept developed here could 
be the basis of a tool to estimate recruitment based on 
data on wind, temperature, and discharge conditions 
before the fishing season has started. It would then be 
feasible to define a harvest control rule incorporating 
this knowledge to reduce risks of a fishery collapse. It 
must be remarked that in order to have that predictive 
tool, there is considerable room for improvement in the 
current model configuration (e.g., varying F, etc), but 
we have proved in this study that even with simpler 
assumptions, the model can yield useful results. 
Finally, although the implementation of our model 
is designed for the European anchovy in the Gulf of 
Cadiz, the fact that Equations 1 and 2 can easily be 
modified for other species and stocks allows the model 
to be easily adapted and applied to other small pelagic 
species for which recruitment is key to explain the sur¬ 
plus or collapse of a fishery. 
Acknowledgments 
The research leading to these results has received 
funding from the European Union’s Seventh Frame¬ 
work Programme (FP7/ 2007-2013) under grant agree¬ 
ment 244706/ ECOKNOWS project and M. Rincon was 
funded by P09-RNM-5358 of the Junta de Andalucia. 
However, the article does not necessarily reflect Eu¬ 
ropean Commission (EC) views and in no way antici¬ 
pates future policy of the EU in the area. We grate¬ 
fully thank CESGA (Galician Supercomputing Center) 
for computational time at the SVG supercomputer and 
technical assistance. 
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