ecological effects of marine protected areas empafish project ...

EMPAFISH Booklet no. 1 Ecological effects of Atlanto-Mediterranean MPAs in the EU
anthropogenic wastes were also studied in the central side of the Gulf (Calvo
& Genchi 1989; D’Anna et al. 1985; D’Anna et al. 1990; Riggio et al. 1992;
Riggio et al. 1994). A few studies were carried out on the rocky bottom
assemblages of the Zingaro Reserve (Riggio et al. 1985; Sparla & Riggio
1990; Badalamenti et al. 1992a, 1992b; Suriano et al. 1992), which is a
partially protected area located along the west side of the Gulf.
Several studies were conducted to investigate the oceanographic features of
the area, but very few data have been published (Genovese 1996).
o Aquaculture
In the 1990’s the Gulf’s coastal zone has been used for pilot studies in the
open sea culture of fish and bivalves (Mazzola 1993, 1996; Sorvillo et al.
1993, 1994; Mazzola et al. 1996; Vega Fernandez et al. 2003); offshore cages
are now used for the culture of bass and bream and for the stabulation of
bluefin tuna. The co-occurrence of artificial reefs, offshore cages and trawl
ban make the Gulf a particularly complex area under the aspect of fisheries
and coastal management (Pipitone et al. 2004).
o Feeding ecology of fishes
Several studies have been carried out on fish species at the fishery reserve
of Castellammare (Badalamenti et al. 1993b; Pepe et al. 1996; Lipari et al.
1998; Pepe et al. 1998). The diet of Dipodus annularis, Lithognathus
mormyrus and Mullus barbatus have been investigated in the Artificial Reef
Area and in Control Areas while for Diplodus sargus and D. vulgaris data
only exists for the Artificial Reef Area. Furthermore, the daily food intake of
M. barbatus and D. annularis has been estimated. Results show that only
D. vulgaris has a strong trophic link with the artificial substrates and that
the other species depend more on the surrounding soft substrates and on
the Cymodocea nodosa seagrass meadow nearby for food.
M. barbatus has a circadian feeding rhythm, with peaks of stomach fullness
after dawn and before dusk. Food consumption varies from approximately 2
and 6 percent of the body weight and depends on seasons. D. annularis has
only one peak during the middle of the day and does not feed at night.
Food consumption is about 3% of the body weight. Data are also available
on the diet and on the daily food consumption for the juveniles of Seriola
dumerili hovering underneath FADs (Badalamenti et al. 1995b;
Badalamenti et al. 1998).
� The fishery reserve
o Effect on fish biomass
The first study on the effect of the year-round trawl ban imposed on the Gulf
of Castellammare was carried out in 1994 (Pipitone et al. 1996, 1997b, 2000).
To assess the effect of the ban on the abundance of demersal resources,
CPUEs from experimental trawl surveys carried out before the ban (spring
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