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Abstract(s)
Small-scale vertical patterns of larval distribution
were studied at a very nearshore larval Wsh
assemblage, during the spring–summer period of several
years, at two depth strata (surface and bottom)
using sub-surface and bottom trawls. A total of 4,589
larvae (2,016 from surface samples and 2,573 from bottom
samples) belonging to 62 taxa included in 22 families
were collected. Most larvae belonged to coastal
species. Although inter-annual variations in larval density
and diversity could be found, total larval abundance
was always higher near the bottom whereas
diversity was higher at the surface. A marked distinction
between the structure of surface and bottom
assemblages was found. Sixteen taxa explained 95% of
the similarity among surface samples. Larvae which
contributed most to this similarity included species like
clupeiformes, sparids and serranids, and also blenniids,
tripterygiids and some labrids. In the bottom samples,
fewer species were present, with only six taxa, almost
exclusively from species which lay demersal eggs, contributing
to 95% of the similarity between samples.
Larvae present at the surface were signiWcantly smaller
than at the bottom. For some of the most abundant
species found at the bottom, only small larvae occurred
at the surface while the whole range of sizes was present
at the bottom, indicating that larvae may be completing
the entire pelagic phase near the adults’ habitat. These results indicate that larval retention
near the reefs probably occurs for these species,
although for others dispersal seems to be the prevailing
mechanism.
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Citation
Marine Biology, 151, 1349-1363