Page 1 - MANNINO_BALISTRERI

50° Congresso della Società Italiana di Biologia Marina
Livorno, 10-14 giugno 2019
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A.M. MANNINO, P. BALISTRERI*

Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche, Università di Palermo,
Via Archirafi, 38 - 90123 Palermo, Italia.
annamaria.mannino@unipa.it
*Vicolo Giotto, 6 - Favignana (TP), Italia.

ARE MARINE PROTECTED AREAS (MPAs) EFFECTIVE
IN PROTECTING FROM INVASIVE SPECIES?
THE CASE STUDY OF CAULERPA CYLINDRACEA SONDER
(CAULERPALES, CHLOROPHYTA) AT EGADI ISLANDS MPA

LE AREE MARINE PROTETTE (AMP) SONO EFFICACI
NELLA PROTEZIONE DALLE SPECIE INVASIVE?
IL CASO STUDIO DI CAULERPA CYLINDRACEA SONDER
(CAULERPALES, CHLOROPHYTA) NELL’AMP ISOLE EGADI

Abstract - The main purpose of Marine Protected Areas (MPAs) is biodiversity conservation. The effects
that invasive species have on MPAs, and vice versa, are still not completely known, even though their
assessment is crucial for MPA management and conservation purposes. In this respect, monitoring plans
are essential and the involvement of citizen scientists may be fundamental. Our experience of Caulerpa
cylindracea Sonder 1845 monitoring within the Egadi Islands MPA highlighted that the alga is widespread
within the MPA, mainly at Favignana Island, also threatening valuable habitats such as vermetid reef and
coralligenous formations. Moreover, Favignana is the island of the Aegadian archipelago most affected by
the introduction of non-indigenous species. Since invasive species are likely to continue to expand, and
further arrivals are to be expected, additional management actions (e.g. concerning tourism activities)
should be taken in MPAs to effectively control invasive species.

Key-words: Caulerpa cylindracea, invasive alien species, Marine Protected Areas, Mediterranean Sea,
monitoring.

Introduction - The introduction of non-indigenous species (NIS, i.e. organisms
introduced outside of their natural, past or present, range and outside of their natural
dispersal potential) has been pointed out as a major driver of global change, threatening
biodiversity and natural ecosystem functioning (Katsanevakis et al., 2014; Vergés et
al., 2016). NIS may in time become invasive (i.e. invasive alien species (IAS)) and
may cause biodiversity loss and ecosystem service changes (Vergés et al., 2016). The
Mediterranean Sea, currently hosting approximately 1000 NIS, is considered a hotspot
of marine biological invasions (Occhipinti-Ambrogi et al., 2011a, 2011b; Katsanevakis
et al., 2014). Sicily and its surrounding islands, including a high number of Marine
Protected Area (MPAs), is particularly vulnerable and prone to NIS invasions due to its
geographic position and the intense maritime traffic volumes (Occhipinti-Ambrogi et
al., 2011a, 2011b; Katsanevakis et al., 2014). Biological invasions may severely affect
MPAs, whose major aim is biodiversity conservation. Until now, the effects of MPAs
on IAS are doubtful (Giakoumi and Pey, 2017). It is unclear if MPAs are able to hinder
IAS expansion, due to the high species richness conferring them an ‘invasion
resistance’, or they may instead favour their introduction and spread through tourism
activities, which increase disturbance and vectors (boat anchors, diving, etc.)
(Giakoumi and Pey, 2017). To reduce the risk of future IAS introduction in MPAs and
to better understand their invasive potential and spread dynamics, monitoring programs

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