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•   time, money, or gear loss by fishermen due  trawl fisheries / bottlenose dolphin interactions
                   to cetaceans interacting with fishing opera-  off the Israeli coast (Goffman et al. 1995, 2001).
                   tions, or getting caught in nets;             In addition to these areas, some information
               •   a real or perceived ecological competition  exists on conflicts between cetaceans and fisher-
                   with cetaceans, based on the conviction that  ies in several Mediterranean areas, including the
                   depredation –  particularly by dolphins -  re-  Thracian Sea (Mitra  et al.,  In press), the Am-
                   duces the amount of fish available to fisher-  vrakikos Gulf, Greece (I. Siori and E. Hatzidimit-
                   ies (Reeves et al. 2001).                  riou, pers. comm.), the Ionian Sea (Tringali et al.,
                  Beneficial effects may also occur. These may   In press), the sea area off Tunisia (Lofti  2000),
               involve dolphins “co-operating” in fishing opera-  the Tyrrhenian Sea (Consiglio  et al.  1992, Mussi
               tions, or otherwise increasing the chances of suc-  et al.  1998), and the Gibraltar Strait (De Stepha-
               cess of a fishery (e.g., Pryor et al. 1990). Indirect  nis et al. 2000, Pèrez Gimeno et al., In press).  In
               beneficial effects may include cetaceans making   the past, there have also been recorded interac-
               an area more attractive to tourists, thus providing  tions between false killer whales,  Pseudorca
               economic advantages (e.g., increased request for   crassidens, and tuna fisheries in the Messina
               seafood) that may positively impact local fisher-  Strait, Italy (Scordìa 1939).
               ies. More importantly, marine mammals are es-     Overall, most information on the economic ef-
               sential components of healthy ecosystems, and  fects of dolphin interactions with Mediterranean
               their ecological importance (e.g., Estes  et al.  fisheries is qualitative and inadequately docu-
               1998) is an issue that has been given little con-  mented.  Although it is certain that in some areas
               sideration until the present day.              fishermen suffer from either gear damage, re-
                  The main types of fishing gear used in coastal  duced catch, or time/money loss, no attempt has
               Mediterranean waters where conflict with dol-  ever been made to evaluate trends, nor to quan-
               phins has been reported are bottom-set trammel   tify the costs of such interactions (Reeves et al.
               nets and gillnets. Dolphins also interact with  2001).
               trawl nets, and occasionally with small purse     Most interactions having a negative impact on
               seines targeting pelagic schooling fish (Reeves et  Mediterranean fisheries have involved the com-
               al.  2001). Although perceived conflict is being  mon bottlenose dolphin and the short-beaked
               reported from a number of Mediterranean areas,   common dolphin, which are the most abundant
               there have been few studies aimed at defining the   coastal cetaceans in the Mediterranean (Notarbar-
               extent of the conflict, and estimating the actual  tolo di Sciara and Demma  1994). However, it
               costs to fisheries.                            must be considered that Mediterranean common
                  Studies specifically focusing on fishery-   bottlenose and short-beaked common dolphin
               dolphin interactions have been initiated in a few  populations, which are thought to be geographi-
               Mediterranean areas. In Italy’s Asinara Island  cally isolated from those in the Atlantic Ocean
               National Park, north-western Sardinia, an attempt  (A. Natoli and R. Hoelzel, pers. comm.), have
               has been made to quantify the impact of dolphin   now declined considerably and their numbers are
               depredation in the trammel net fishery for red  certainly not as high as they used to be only 50
               mullet (Mullus surmuletus) (Cannas et al.  1994,  years ago.
               Lauriano et al., In press).  In two  areas of Sicily   Today, the common bottlenose dolphin  – that
               (Catania and Favignana) a European Commis-     in the basin is typically found on the continental
               sion-sponsored study (project ADEPTs) has been   shelf - remains the species involved in most cases
               initiated to test the feasibility and efficacy of us-  of interactions with coastal fisheries, although its
               ing pingers to reduce dolphin depredation in  populations appear to be increasingly scattered
               trammel and gill net fisheries (Quero et al. 2000).    and fragmented into small units.
               Studies conducted by the University of Barcelona   Interactions with Mediterranean fisheries have
               in the Balearic Islands from 1992-95 indicated  also involved the short-beaked common dolphin,
               that about 30 bottlenose dolphins were dying an-  but the current extent of such interactions is lim-
               nually as a result of entanglement or direct killing  ited by the fact that the species has faced a dra-
               by fishermen, in retaliation for depredation on  matic decline in numbers over the past few dec-
               trammel nets and shore-anchored gill nets set for   ades. The forthcoming revised IUCN/SSC action
               red mullet and cuttlefish (Sepia officinalis) (Sil-  plan recognises that short-beaked common dol-
               vani et al. 1992, Gazo et al., In press).  Finally,   phins in the central and eastern Mediterranean
               research is underway to evaluate the dynamics of  have declined precipitously and that conservation

                                    Cetaceans of the Mediterranean and Black Seas   –   9.3
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