Despite extensive knowledge of the genetic structure of sea bass
(Dicentrarchus labrax) populations, no studies have investigated genetic structure within early
life stages, or compared such structure between such stages and (sub)adults.
Using nine newly developed microsatellite loci, we investigated patterns of
genetic variation and relatedness among juveniles that settled in two NW
Mediterranean nursery grounds in close geographical proximity. There was no
evidence for differentiation among samples at settlement (θ = -0.0010), and
no significant genetic relatedness. Nevertheless, significant departures
from Hardy-Weinberg equilibrium were detected in each sample, which could
not be attributed exclusively to the presence of null alleles and to Wahlund
effect. These results are compared with and discussed in relation to the
genetic structure of adults described in the same area 10 years ago.