Page 2 - Balistreri_Mannino_2017
P. 2
106 Paolo Balistreri &Anna Maria Mannino
Agardh var. distichophylla (Sonder) Verlaque, MATERIAL AND METHODS
Huisman et Procaccini, recently recorded in Sicily
(in 2007 as C. distichophylla in Meisnez et al., Study area
2010; Jongma et al., 2013; Musco et al., 2014),
have raised serious ecological and economic con- The study was carried out at Favignana Island
cern. (Egadi Islands MPA), located approximately five
Sicily and smaller surrounding Islands, located kilometers from the western coast of Sicily. The Is-
at the crossroads between the eastern and western land, part of the Aegadian Archipelago, represents
sectors of the Mediterranean Sea and characterized an example of a lower Pleistocene bioclastic cal-
by intense maritime traffic (Occhipinti-Ambrogi et carenite, characterized by a typic association known
al., 2011; Coll et al., 2012; Katsanevakis et al., as foramol (Kil, 2010). More or less continuous ver-
2014), are particularly vulnerable and suitable to metid reefs are present along the coasts of Favig-
biological marine invasions (Bianchi, 2007; Oc- nana, consistent with the true reefs described along
chipinti-Ambrogi et al., 2011; Katsanevakis et al., the north-western Sicilian coasts (Antonioli et al.,
2012; Papini et al., 2013; see also Figs. 2-5 in Kat- 1999; Chemello, 2009). Their distribution confirms
sanevakis et al., 2014) and then can be considered the need of carbonatic substrates and of an abrasion
as important sources for secondary dispersal. Ver- platform for the formation of true reefs (Dieli et al.,
metid reefs are bioconstructions built up by the 2001). Recently, a preliminary description of the
gastropod mollusc Dendropoma cristatum (Biondi, reefs present along the coasts of Favignana Island
1859) (Vermetidae) in association with some was provided (Balistreri et al., 2015; Table 1).
coralline algae such as Neogoniolithon brassica-
florida (Harvey) Setchell et Mason. These biocon- Sampling and Data analysis
structions play a fundamental structural role, as they
protect coasts from erosion, regulate sediment Surveys were carried out in summer 2015 in ten
areas, characterized by the presence ofa vermetid reef
transport and accumulation, serve as carbon sinks,
make the habitat more complex and heterogeneous (Fig. 1). Five areas were selected along the north-
ern side: Faraglione, Pozzo, Arre Turinu, San Gi-
and provide numerous habitats for animal and ve-
useppe, San Nicola, and five along the southern side:
getal species thus increasing intertidal biodiversity
(Pandolfo et al., 1992, 1996; Badalamenti et al.,
1998).
Pattern 1 Outer Margin: wide, flattened and ir-
These biogenic constructions, enclosed in the
regular. In the inner side, crevices were
SPA/BIO Protocol (Barcelona Convention) are now
also present.
threatened by environmental changes and human
Inner Margin: Dendropoma cristatum
activities (e.g. pollution, climate change, ocean is absent.
acidification) thus experiencing high mortality in Cuvettes: not many, not deep and with
several areas of the Mediterranean Sea (Di Franco a variable width.
et al., 2011; Galil, 2013; Milazzo et al., 2014). Pattern 2 Outer Margin: thin and not continuou-
Marine Protected Areas (MPAs), even though have sly arranged.
Inner Margin: Dendropoma cristatum
a strong potential for habitat and biodiversity con-
is absent.
servation, seem to be not effective in protecting
Cuvettes: not many and not deep.
from the different threats and then from biological
Pattern 3 Outer Margin: it has a variable height
invasions, sometimes enhancing them (e.g. Byers,
and sometimes it is absent. Some crevi-
2005; Klinger et al., 2006; Burfeind et al., 2013).
ces can also be present together with
Since the increase of knowledge is essential for the regrowth areas.
conservation and protection of this highly valuable Inner Margin: Dendropoma cristatum
and vulnerable habitat, with this study we provide is absent.
Cuvettes: many and sometimes very
a first baseline assessment of the distribution and
deep.
abundance of alien macroalgae in the vermetid
reefs present along the coasts of Favignana Island
Table 1 Local patterns of vermetid reef observed at
.
(Egadi Islands MPA). Favignana Island (Balistreri et al., 2015).
