G. Danna et al., INFLUENCE OF ARTIFICIAL REEFS ON COASTAL NEKTON ASSEMBLAGES OF THE GULF OF CASTELLAMMARE (NORTHWEST SICILY), Bulletin of marine science, 55(2-3), 1994, pp. 418-433
An artificial reef, of 32 pyramids of concrete block, was built in the
coastal waters of the Gulf of Castellammare (NW Sicily) during 1986-1
989. Our research objective was to compare the catches and nekton asse
mblage structure of this reef with those of surrounding natural habita
ts. Surveys were carried out in 1990-1991 at three different sites: th
e artificial reef area (ARA), a natural rocky area (NRA) and a control
area on a sandy bottom (CA). A trammel net was used to obtain samples
at each site, and a qualitative visual assessment of the fish assembl
age of ARA was also carried out. Quantitative analysis showed that ARA
had significantly more species and a greater number of specimens than
CA but no significant difference in catches was recorded, while a gen
eral similarity in the nekton assemblage was found comparing ARA and N
RA. Overall, ARA displays features intermediate between the two natura
l sites tested, and the variability of its assemblage could be attribu
ted to the availability of shelter and to the benthic settlement on th
e concrete boulders. This study is an attempt to understand the role p
layed by artificial reefs in influencing the composition of nekton ass
emblages in oligotrophic waters, such as those in the southern Tyrrhen
ian Sea.