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nodulosa has been collected from between the branches of dead Lopehlia and errant
species included the echinoid Cidaris cidaris, the gastropod Coralliophilia richardi, and the
crab Anamanthia rissoana.

The structural complexity of the deep-water coral reefs, acting as essential habitats for
feeding and spawning, can also attract cephalopods, crustaceans, and fishes, as well as
studies on prokaryotic assemblages associated with the deep-sea coral Lophelia pertusa in
the Central Mediterranean Sea revealed specific and unique microbial assemblage
(Danovaro, 2010).

5.2 Ocean triads and the effect of AIS on anchovy spawning

In the Mediterranean Sea, summer has been found to be the only season of the year not
characterized by very high rates of mechanical energy added to the water column by the
wind. Hence, during the rest of the year, turbulent mixing intensities are high in areas
exhibiting linked enrichment and concentration processes, and appear to preclude conditions
that may characterize favourable reproductive habitats. Other areas, however, have been
found representing apparent large-scale ocean triads during the summer season. They can
then be considered as potentially very favourable reproductive habitats, considering the
arrangement of physical mechanisms. The Sicily Channel is one of the areas found by
Agostini and Bakun (2002) where ocean triads - e.g. enrichment processes (upwelling,
mixing, etc.); concentration processes (convergence, frontal formation, water column
stability) and processes favouring retention within (or drift toward) appropriate habitats - are
located. In the Mediterranean Sea, ocean triads appear to be associated particularly with
summer conditions, and interestingly, summer is also the seasonal spawning period for
anchovies and sardines, as well as other important pelagic fish such as tunas (Agostini and
Bakun, 2002, Iglesias et al., 2003).

It has been difficult to locate much of the information published on anchovy reproduction off
Tunisia. Anchovy eggs were found and reported in a survey conducted in 1972 (Ktari-
Chakroun, 1979), but in spite of their comparatively high values, anchovies, even during that
period, never attained more than 9% of the pelagic landings in the area.

Anchovy spawns along the narrow shelf off the southern Sicilian coast, from Sciacca to Gela
(Garcia-Lafuente et al., 2002). The most important spawning ground is located off Sciacca,
where a branch of the Atlantic Ionian Stream (AIS) impinges the coast.

Other places can provide similar favourable spawning conditions, such as the region off
Cape Passero. East of Cape Passero, the continental shelf drops sharply and by lateral
friction with the coastline to the left side of the jet, it makes a northward bending with a
cyclonic circulation cell of the AIS, flowing into the deep Eastern Mediterranean Basin (Fig.

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