download pdf

Mediterranean and Black Sea Cetacean Red List Assessment
Balaenoptera physalus
Canada, Greenland, Iceland and Spain (Bérubé et al. 1998). Further genetic analyses (Palsbøll et al.
2004) predicted that Mediterranean fin whales would prove to be largely resident in the basin, although
limited but recurrent gene flow was detected in the data. Direct evidence supporting this prediction was
later provided through satellite tagging (Guinet et al. 2005).
Fin whales are regularly encountered throughout the western and central basins, with seasonal summer
concentrations in highly productive portions of the Corsican, Ligurian and Tyrrhenian seas, where they
apparently feed on a single euphausiid species, Meganyctiphanes norvegica (Orsi Relini et al., 1998).
Limited evidence exists of similar feeding activities in the eastern Ionian Sea (Notarbartolo di Sciara et al.
2003). Seasonal (late winter) feeding aggregations of fin whales have also been observed recently in the
Sicily Channel (Canese et al. in press). Photo-identification data imply a high degree of site fidelity in fin
whales summering in the Ligurian Sea (Zanardelli et al., 1998). Breeding and calving grounds have yet to
be identified (Notarbartolo di Sciara et al., 2003). Fin whales are extremely rare in the Adriatic and Aegean
Seas, and in the Levant Basin.
No population estimates exist for the entire region. However, line-transect surveys yielded estimates of
3,583 fin whales (S.E. 967, 95% C.I. 2,130-6,027) over a large portion of the western Mediterranean in
1991 (Forcada et al., 1996), and 901 (S.E. 196.1, 95% C.I. 591-1,374) in the Corsican-Ligurian-Provençal
basin in 1992 (Forcada et al. 1995). Further line-transect survey effort in the same area yielded a strikingly
consistent density estimate of 0.015 individuals km -2 (Gannier, 1997).
Habitat and Ecology
Fin whales in the Mediterranean are most common in deep waters (400 to 2,500 m) but they can occur
in slope and shelf waters as well, depending on the distribution of their prey (Gannier et al. 2002,
Notarbartolo di Sciara et al. 2003, Panigada et al. 2005). They favour upwelling and frontal zones with high
zooplankton concentrations.
Threats
Incidental mortality of fin whales in fishing gear (pelagic driftnets) is uncommon (Podestà and Magnaghi,
1989) and its effect on the population is therefore considered low but not negligible (International Whaling
Commission, 1994). Ship strikes also cause mortality and are a concern particularly in areas of heavy
vessel traffic (Cagnolaro and Notarbartolo di Sciara 1992, Panigada et al. 2006, Weinrich et al. 2006). The
increasing use of high-speed ferries bears watching in this regard. Shipping noise and vessel disturbance,
particularly from the unregulated whale watching that has recently begun in the area (Airoldi et al., 1999),
is another source of concern. Contamination by organochlorines and trace elements is not as high in fin
whales as in odontocetes from the same region, but the reverse is true for DDT metabolites (Fossi et al.,
2003).
Conservation measures
A large international protected area (approx. 90,000 km 2 ), the Pelagos Sanctuary for Mediterranean
Marine Mammals, was recently established and listed among SPAMIs (Barcelona Convention SPA
Protocol), encompassing a key fin whale feeding area in portions of the Provençal, Corsican, Ligurian,
Tyrrhenian and northern Sardinian Seas. Whale watching regulations are likely to be incorporated into
national legislation in the near future. The species is listed in Appendix I of CMS, in Appendix II of the
Bern Convention, in Appendix I of CITES, and in Annex 2 of the Protocol on Specially Protected Areas
and the Biological Diversity in the Mediterranean of the Barcelona Convention. For the present at least,
Mediterranean fin whales are protected by the International Whaling Commission’s moratorium on
commercial whaling that came into force in 1986.
Data Sources
Airoldi, S., Azzellino, A., Nani, B., Ballardini, M., Bastoni, C., Notarbartolo di Sciara, G. and Sturlese,
A. 1999. Whale watching in Italy: results of the first three years of activity. European Research on
Cetaceans 13:153-156.
Bérubé M., Aguilar A., Dendanto D., Larsen F., Notarbartolo di Sciara G., Sears R., Sigurjonsson J., Urbàn
R., Palsbøll P. 1998. Population genetic structure of North Atlantic, Mediterranean Sea and Sea of
Cortez fin whales, Balaenoptera physalus (Linnaeus, 1758); analysis of mitochondrial and nuclear
Annex 3: Regular Species 14