Ligas et al.: Modeling the growth of recruits of Merluccius merluccius in the northwestern Mediterranean Sea 
79 
ability and protection to predation) enhance juvenile 
condition and growth. 
Juveniles of European hake are exposed to trawl 
fisheries after bottom settlement in their nursery 
grounds. Therefore, a reduction in fishing mortality of 
immature fish could be a fundamental prerequisite for 
sustainable fisheries. The implementation of the fol- 
lowing requirements — use of a large mesh size, square- 
mesh panels, and selection grids in trawl fisheries — has 
reduced the bycatch of juvenile European hake (Sarda 
et al., 2004; Lucchetti, 2008). However, these measures 
may not be sufficiently effective in protecting juveniles 
and nursery areas. In fact, the use of gear selectivity as 
a fishery management tool without adequate research 
into the fate of escaping juvenile fish should be cause 
for concern for any fishery (Chopin and Arimoto, 1995). 
Moreover, trawling activities are known to cause alter- 
ations to the bottom of the seafloor, reducing habitat 
complexity and altering benthic community structure 
(Kaiser et al., 2002), both of which are fundamental 
components of habitat for juvenile European hake. 
Therefore, a deeper understanding of the importance 
of the quality of recruitment habitats (i.e., nurseries) 
on the growth and the survival of juveniles of Euro- 
pean hake is a challenging task that could be relevant 
for conservation purposes (e.g., protection of nursery 
grounds). 
Acknowledgments 
The authors are grateful to the 3 anonymous reviewers 
for their comments and suggestions, which contributed 
to improvement at the manuscript stage. 
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