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reefs  (AR)  [4]. AR  are  heavy concrete  constructions   of basic data  by  non-experienced divers called  for
           which can be armoured with extruding steel bars. These   biannual (June  and December)  field activities to
           have been recognized as  one of the most effective   be performed in the same localities (GPS  located),
           tools for integrated management and conservation   before (as reference) and after the AR deployment. Six
           of coastal resources after the establishment of Marine   localities around Favignana Island where chosen by the
           Protected Areas, particularly for P. oceanica habitat and   MPA authority for monitoring (Figure 1). In each locality,
           its associated halieutic resource [5].             five sampling sites were randomly chosen along a 50 m
           In order to limit the impact of trawling on the largest   transect parallel along the shore at 12 m depth. At each
           P. oceanica meadow in the Mediterranean, in 2013   sampling site,  P.  oceanica canopy cover was visually
           the Egadi Islands’ MPA authority, within the MASTER   estimated on a circle with a 5m radius. Shoot density was
           project, adopted protective measures by deploying   estimated by counting the number of shoots in six sub-
           AR within 50 m of depth in well-identified, sensitive   quadrats (20×20 cm), randomly selected on a gridded
           areas. According to the Italian law, trawling is banned   quadrat of 1m . Shoot percent cover was calculated as
           at  depths lower than  50  m or at  less than  3  nautical   the percentage of sub-quadrats containing P. oceanica
           miles from the coastline.  To measure the status  and   shoots in a total number of 25 quadrats [10]. Along the
           trends of meadows over time and analyze the changes   same transect, abundance of fish species censused
           of associated fish species, a long-term monitoring has   in the water  column (hereafter called  ‘pelagic’) and
           been set up. Long-term monitoring is essential in any   on the bottom (hereafter called  ‘necto-benthic’)  was  Research & development
           protective or recovery initiative in order to address its   estimated trough visual census performed by 2 divers
           effectiveness [6].  Here the preliminary  results  on the   at the same meteo conditions, and between 10 and 14
           collaboration between the ENEA’s Marine Environment   daytime. Visual census was made at a depth of 3, 6, and
           Research Center and the Egadi Islands’ Marine      12 m at the beginning and at the end of each transect
           Protected Area (MPA) are reported, presenting the   and at two random, replicate points along the transect
           results of the training activities (September 2012) and   at 12 m depth. At each point, fish species abundance
           the preliminary results of monitoring activities carried   was evaluated, sampling a circular  area (360°) with
           out by the MPA divers in May-June 2013 (before the AR   a diameter  of 5 m. Hence  4 pelagic and 4 necto-
           deployment)  and February 2014. A brief discussion   benthic  fish  abundance  was estimated. During  the
           on the pros and cons of the methods employed is also   survey, seawater temperature (°C), visibility (m), wind
           reported.                                          direction, and current direction were recorded.
                                                              As the level of personal experience may bias the results of
                                                              visual evaluation of P. oceanica cover and fish visual census,
           Materials and methods                              an intensive training was done in September 2012 by
                                                              ENEA marine biologists for MPA divers, to standardize the
           AR were deployed in June  2013 in several localities   procedures and the observers’ ability to collect accurate
           chosen by the MPA authority around the Egadi Islands.   data, before the official sampling started. For visual
           Each AR unit was composed by a Technoreef® module   census of fish, underwater tablets with images of the most
           called Stopnet, equipped with special hooks designed   representative pelagic and necto-benthic species known
           to trap nets and release cords or cables. Stopnet was   for the area were fixed up. After a briefing on fish and
           placed in straight line  running  out from  the coast,   P. oceanica counting methods, two non-experienced MPA
           forming a barrier to illegal trawling activity.    divers were trained during a preliminary survey. Surveys
           An  appropriate follow-up monitoring  protocol  to be   were carried out in three days by two couples of divers,
           applied by the MPA marine biologists was set up by   each formed by one MPA diver and one ENEA diver. The
           ENEA  researchers  for measuring changes of both   following dives were scheduled: Cala Rossa West (CRw)
           seagrass abundance  parameters and associated      and Cala Rossa Center (CRc) the 3rd of September;
           pelagic  and  necto-benthic fish assemblages [7,  8,  9].   Cala Rossa East (CRe) and Cala Monaci East (CMe) the
           The protocol was defined to ensure an easy collection   6th of September; Cala Monaci Center (CMc) and Cala

                                                                                  EAI    Energia, Ambiente e Innovazione    4/2015
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