[Abstract] Coastal areas have been widely considered as nurseries for many marine
species. New approaches to this concept take into account interactions among
environmental variables and ecological variations related to geographical location, as
well as complex life cycles of marine invertebrates. We present a comparative approach
to assess the relevance of environmental variables on the determination of patterns of
distribution and habitat use of benthic decapod species in coastal areas. We
hypothesize that this approach allows us to infer processes originating these patterns
and to identify the main habitat use models. An intensive fine-grain sampling design
was used to take into account the environmental gradients occurring at different spatial
scales (defined by substrate type, depth, exposure and geographical location) in a
temperate oceanic bay (Ria de A Coruña, Spain). A high proportion of juveniles were
found in most populations, but the results do not allow us to generalize the idea of
coastal areas as potential nurseries, except for few species with a marked spatial
segregation between juveniles and adults. Larval transport seems to be the main
process regulating mesoscale distribution patterns, while microscale distribution
responds to a complex interaction among different processes, i. e. habitat selection at
settlement, differential mortality among habitats, post-settlement dispersal and
ontogenetic habitat shifts. Sandy substrates showed low-diversity communities
dominated by hermit crabs. In rocky bottoms, variability in spatial patterns was mostly
related to substrate type and geographical location. Caridean shrimps showed higher
densities on flat rock surfaces, with similar juvenile and adult patterns. Anomuran species occurred mainly on cobbles. Distribution patterns of brachyurans varied among
species, but did not change greatly from juveniles to adultsMinisterio de Ciencia y Tecnología; REN2000 –0446MARMinisterio de Ciencia y Tecnología; REN2003-04816Xunta de Galicia; XUGA10301B9
