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Sperm whale residency and movements within the Mediterranean Sea were investigated using photo-identification data collected in summer over a 15 year period (1991–2005). Surveys were conducted from a 12 m motor sailing boat. Although dedicated to cetaceans, surveys did not solely focus on sperm whale photo-identification, so time to track and photograph all individuals forming a group was not always available. From good quality photographs, 44 individuals were identified in the western Mediterranean, including the Ligurian Sea, the Gulf of Lions and waters off the Balearics. Eleven identified whales were photographically re-captures. Within-year re-sightings occurred from 1 to 29 d apart, while five identified whales were re-sighted over several summer seasons, from 1 to 7 y apart. Four whales were seen in more than one year in the northern part of the basin, indicating site fidelity to this feeding area. The combination of photo-identification and acoustic data (size estimation from inter-pulse interval measurements) enabled us to demonstrate a north–south movement of some sexually mature males (around 13 m in length), feeding in the northern regions and joining groups of females off the Balearics for around 20 d. These displacements ranged over ~500 km, with travelling time of seven days or less.

A specimen of Chaunoteuthis mollis (Cephalopoda: Onychoteuthidae), a mature mated female, from the Straits of Messina was examined. Measurements and indices were compared with those of Onychoteuthis banksii reported by previous authors. The differences found were attributed to the degeneration of the C. mollis specimen, due to sexual maturation. Two subocular (one under each eye) and two visceral photophores, similar to those of O. banksii, were present in the C. mollis specimen. The size of the posterior visceral photophore of C. mollis fit the regression line correlating posterior photophore diameter to mantle length in O. banksii. These results corroborate the hypothesis, put forward by other authors, that C. mollis represents the mature female of O. banksii.

Since 1980 many papers dealing wholly or partly with the genus Fenestrulina have been published, mainly by Anglo-Saxon and South American authors: e.g. Gordon (1984, 1989), Hayward (1980), Hayward & Ryland (1990), Hayward & Taylor (1984), Moyano (1985). These studies have increased the number of species of the genus known around the world. However, few authors have worked on the genus Fenestrulina in European seas, probably because it was assumed that this taxon was well known in these regions.

A new species, Oikopleura villafrancae, from the family Oikopleuridae (Lohmann 1915), subfamily Oikopleurinae (Lohmann 1896), genus Oikopleura (Mertens 1830), is described from numerous specimens collected at mesopelagic depth (360–880 m) during two different cruises: Migragel II (May 1988) and Medapp (May 1990) in the Ligurian Sea (northwest Mediterranean) between Villefranche-sur-Mer (French Riviera) and Corsica, respectively by the ‘Cyana’ and ‘Johnson-Sea-Link’ manned submersibles.

The impact of date-mussel fishery on substratum rugosity was evaluated at Capo Noli and Isola di Bergeggi (Savona, north-western Italian coast) in the summer of 2004. A new measure of substratum rugosity was used as a surface-dependent index of complexity. The results were compared between impact and control sites using two-way analysis of variance and suggested that the mussel fishery reduces substratum complexity.