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Reduced prey availability and nutritional  ber of cetacean species as food reservoir, thus
               stress may be an issue in the reduced dolphin  making them more exposed to their toxic effects
               abundance or mass mortality events observed in  at a time when they are already debilitated by
               several Mediterranean areas. For instance, an un-  food scarcity.
               usually high effort devoted to food search has
               been recorded for Mediterranean common bottle-
               nose dolphin population units that have been  List of references
               consistently studied during the last decade (Politi
               1998, Bearzi et al. 1999). Approximately 40% of   Agardy T., Engdahl S. In press. Marine protected area net-
                                                                 works and corridor approaches: Optimal ways to con-
               “resident” common bottlenose dolphins in the      serve ecosystem integrity. Conservation Biology in
               eastern Ionian Sea, where demersal fish resources   Practice.
               have been over-fished (Papaconstantinou et al.   Aguilar A. 2000. Population biology, conservation threats
               1985a,b) were reportedly emaciated (Politi et al.   and status of Mediterranean striped dolphins (Stenella
                                                                 coeruleoalba). Journal of Cetacean Research and Man-
               2000).  In the same area, a decline in short-     agement 2:17-26.
               beaked common dolphin numbers was consistent   Aguilar A., Raga J.A. 1993. The striped dolphin epizootic in
               with the hypothesis of reduced prey availability  the Mediterranean Sea. Ambio 22(8):524-528.
               or increased prey patchiness (Politi and Bearzi, In   Alverson D.L., Freeberg M.H., Murawski S.A., Pope J.G.
               press).  In Mediterranean striped dolphins, inade-  1994. A global assessment of fisheries bycatch and dis-
                                                                 cards. FAO Fisheries Technical Paper 339. Food and
               quate nutrition has been cited possibly having    Agriculture Organization of the United Nations, Rome.
               played a role in an epizootic outbreak (Aguilar   233 pp.
               and Raga  1993) and to be responsible for their  Alverson D.L., Hughes S.E. 1996. Bycatch: From emotional
               extremely elevated age at sexual maturation ob-   to effective natural resource management. Reviews in
                                                                 Fish Biology and Fisheries 6:443-462.
               served in this region as compared to other con-  Andreoli M.G., Campanella N., Cannizzaro L., Garofalo G.,
               specific populations inhabiting waters were food   Giusto G.B., Jereb P., Levi D., Norrito G., Ragonese S.,
               resources were more abundant (Calzada  et al.     Rizzo P., Sinacori G. 1995. Rilevazione campionaria
               1996, Aguilar 2000).                              delle statistiche della pesca nelle marinerie di sicilia Me-
                                                                 ridionale (MINIPESTAT): Data report. N.T.R.-I.T.P.P.
                                                                 Special Publication 4, Vol. 2. 234 pp.
               Risky synergies.   Several factors other than   Anonymous.  2000. L’acquacoltura in Grecia: successo e
               overfishing may contribute to a reduced prey      ansie. La Pesca Europea 2:4-5.
               availability, or induce changes that can affect the   Apanius V. 1998. Stress and immune response. Pp. 133-153
               marine food webs. For instance, global environ-   in  A.P. Møller, M. Milinski and P.J.B. Slater (Eds.)
               mental changes (MacGarvin and Simmonds            Stress and behavior. Vol. 27 in Advances in the study of
                                                                 behavior. Academic Press, London.
               1996) may combine with overfishing and habitat  Arcand–Hoy L.D., Benson W.H. 1998. Fish reproduction:
               contamination to jeopardise ecosystem dynamics.    An ecologically relevant indicator of endocrine disrup-
               Moreover, the build-up of man-made toxic con-     tion. Environ. Toxicol. Chem. 17(1):49-57.
               taminants may reduce the reproductive success or   Archer F., Gerrodette T., Dizon A., Abella K., Southern S.
                                                                 2001. Unobserved kill of nursing dolphin calves in a
               depress the immune-responses of top predators,    tuna purse-seine fishery.  Marine Mammal Science
               including both fish and marine mammals (e.g.,     17(3):540-554.
               Fossi et al., In press).                       Ardizzone G.D., Belluscio A., Schintu P. 1994. Considera-
                  The impact of man-made toxic compounds on      zioni sullo strato di sfruttamento delle risorse demersali
                                                                 (Isola di Giannutri  –
                                                                                 Foce del Garigliano).  Biol. Mar.
               biologic communities is a major source of con-    Medit. 1(2):43-46.
               cern. Many organochlorine compounds, for in-   Azzali M., Luna M. 1988. Una nota preliminare sulle risorse
               stance, are responsible for endocrine dysfunc-    pelagiche nei mari italiani, stimate con tecniche acus-
               tions in a number of organisms, including ceta-   tiche. Atti del Seminario delle unità operative responsa-
               cean preys.  By affecting the reproductive suc-   bili dei progetti di ricerca promossi nell'ambito dello
                                                                 schema preliminare di piano per la pesca e l'acquacul-
               cess and the sex ratio of a species, contamination   tura. Vol. 1. Pp. 101-171.
               may negatively affect fish stocks (Focardi et al.   Baker R.R. 1978. The evolutionary ecology of animal mi-
               1998, Johnson  et al. 1988, IEH  1995, Janssen et   gration. Holmes and Meier Publishers, New York. 1012
               al.  1997, Arcand-Hoy and Benson  1998), with  Barone G. 1895. Modificazioni delle abitudini del delfino
               cascade effects on both cetaceans and fisheries.   comune (Delphinus delphis) osservate in Liguria e pro-
                  Finally, it must be observed that contamina-   dotte dal generalizzarsi della pesca intensiva. Neptunia
               tion and food scarcity may act synergistically, as   10:156-164.
               malnutrition may prompt mobilisation of lipo-  Bearzi G., Politi E., Notarbartolo di Sciara G. 1999.  Diurnal
               philic contaminants that are “stored” in the blub-  behavior of free-ranging bottlenose dolphins in the

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