ecological effects of marine protected areas empafish project ...

EMPAFISH Booklet no. 1 Ecological effects of Atlanto-Mediterranean MPAs in the EU
Cerbère – Banyuls: ecological studies
� General
o Fish assemblage
Fish assemblages have been extensively studied in the area since the first
survey by Johann Bell in 1983, using underwater visual census (UVC) as main
the sampling technique. The principal objective has been to study the fish
structure in relation to protection from fishing. Several studies (Tito de Morais
1980; Seloudre 1984) have been undertaken on the same objective leading to
a check-list of fish species for the area (Jouvenel 1992, 1996). Some special
emphasis has been devoted to the emblematic Mediterranean dusky grouper
Epinephelus marginatus (Tissot 1998; Louisy et al. 2001)
o Benthic communities
A complete characterisation of the substratum of the entire MPA was
undertaken in in 2001 (Ballesta 1997; Lenfant et al. 2001) with the objective
to set a management plan for the MPA. Together with this global view,
specific surveys were done in specific locations for Lithophyllum lichenoides
(Fajon & Lestienne 1991), longterm dynamics of fucales (Thibaut et al. 2005),
Posidonia oceanica beds (Pergent-Martini & Pergent 1989, Ballesta 1997,
Claes 2000), red gorgonians (Martinie De Maisonneuve 1996), red coral (L'Œil
d'Andromède 2004), Pina nobilis (Guille & Medionie 1996; Cazes & Gazeilles
1997), sea urchins (Laspougeas 1994), the ascidian Microcosmus sp. (Monniot
1965), and ichtyoplankton assemblage (Crec’hriou 2000).
� Reserve effect (including genetic effect)
o Fish assemblage
Several surveys have been undertaken with the objective to quantify the
impact of the MPA on the fish assemblage in the Cebère/Banyuls MPA. Most of
the studies come from UVC projects (Bell 1983; Jouvenel 1992; Cadoret
1993; Licari 1993; Dufour et al. 1995; Hertel 1995; García Charton & Planes
2002). Fish families responding the best to protection measures –by having
higher abundance and/or biomass within the MPA, are serranid (groupers and
combers) and sparid (sea-breams) species.
Superimposed to the reserve effect, a “habitat effect” on ichtyofauna is
apparent, derived from the fact that this MPA harbour rocky habitats being
more complex (due to the importance of crevices, hangs, vertical walls, etc.)
than neighbouring unprotected areas, which are more heterogeneous (by
having a higher proportion of Posidonia and/or sand embedded in the rocky
matrix), all these differences having a great influence on the structure of fish
assemblage (García Charton & Planes 2002). Hence, some fish species
appeared to be more abundant and/or big in size in unprotected areas used
as control sites (some labrids, other sparids, striped red mullet, etc.), because
they show affinities for these heterogeneous bottoms.
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