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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
-2
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

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