Fish assemblage on natural versus vertical artificial reefs- the rehabilitation perspective

Abstract Arti®cial reefs have been suggested as a po-
tential tool for the restoration of marine habitats. In the
present study, the ®sh assemblage established around the
oil jetties of Eilat (northern Red Sea, Israel) was com-
pared to those found in three adjacent natural reef
habitats: two in a nature reserve (one shallow and one
deep) and a third deep site located near the city. Both
species richness and ®sh abundance were found to be
signi®cantly higher around the vertical structures of the
jetty’s pillars than at all three natural sites, with the
lowest values at the site closest to the city. The higher
species richness at the jetties may be explained by (1) the
vertical relief and high complexity of the jetty which
o€ers a variety of niches for both shallow and deep coral
reef species, and (2) by the reduction in available niches
at the natural sites as a result of coral destruction due to
anthropogenic activity. The pronounced di€erence in
®sh abundance is attributed mainly to the high seasonal
recruitment at the jetty which was much lower at the
natural sites. We therefore suggest that vertical struc-
tures are more attractive to ®sh settlement and recruit-
ment than moderately sloped bottoms such as those
found at the fringing reefs of Eilat. High similarity (51 to
56%) was found between ®sh assemblages at the natural
sites while relatively low similarity (27 to 37%) was
found between the jetty and the natural reefs. The jetty’s
complex vertical arti®cial structures can serve as a model
for future construction of arti®cial reefs designed to re-
store the ®sh community in areas where the natural reefs
have been damaged. It should be taken into account,
however, that these do not necessarily mimic the natural
environment but may rather establish a community of
their own, which is in¯uenced by the spatial orientation
and complexity of the structure.download articel here/ disini