Gnone G.,Acquario di Genoa Area Porto Antico |
Bellingeri M.,Acquario di Genoa Area Porto Antico |
Dhermain F.,GECEM |
Dupraz F.,GECEM |
And 17 more authors.
Aquatic Conservation: Marine and Freshwater Ecosystems | Year: 2011
The Pelagos Sanctuary is the largest marine protected area of the Mediterranean Sea (87 500km2), and is located in the north-west part of the basin. The presence of the bottlenose dolphin in this area is well documented but its distribution and abundance are not well known. The present study collected and analysed data from 10 different research groups operating in the Pelagos Sanctuary from 1994 to 2007. Photo-identification data were used to analyse the displacement behaviour of the dolphins and to estimate their abundance through mark-recapture modelling. Results show that the distribution of bottlenose dolphin is confined to the continental shelf within the 200m isobath, with a preference for shallow waters of less than 100m depth. Bottlenose dolphins seem to be more densely present in the eastern part of the sanctuary and along the north-west coast of Corsica. Bottlenose dolphins show a residential attitude with excursions usually within a distance of 80km (50km on average). A few dolphins exhibit more wide-ranging journeys, travelling up to 427km between sub-areas. The displacement analysis identified two (sub)populations of bottlenose dolphins, one centred on the eastern part of the sanctuary and the other one around the west coast of Corsica. In 2006, the eastern (sub)population was estimated to comprise 510-552 individuals, while 368-429 individuals were estimated in the Corsican (sub)population. It was estimated that in total, 884-1023 bottlenose dolphins were living in the Pelagos Sanctuary MPA in the same year. The designation of a number of Special Areas of Conservation (SACs) under the Habitats Directive is discussed as a possible tool to protect the bottlenose dolphin in the Pelagos Sanctuary and in the whole of the Mediterranean Sea. Copyright © 2011 John Wiley & Sons, Ltd. Copyright © 2011 John Wiley & Sons, Ltd. 21 4 June 2011 10.1002/aqc.1191 Research Article Research Articles Copyright © 2011 John Wiley & Sons, Ltd.. Source
Druon J.-N.,European Commission - Joint Research Center Ispra |
Panigada S.,Tethys Research Institute |
David L.,EcoOcean Institute |
Gannier A.,British Petroleum |
And 7 more authors.
Marine Ecology Progress Series | Year: 2012
The development of synoptic tools is required to derive the potential habitat of fin whales Balaenoptera physalus on a large-scale basis in the Mediterranean Sea, as the species has a largely unknown distribution and is at high risk of ship strike. We propose a foraging habitat model for fin whales in the western Mediterranean Sea relying on species ecology for the choice of predictors. The selected environmental variables are direct predictors and resource predictors available at daily and basin scales. Feeding habitat was determined mainly from the simultaneous occurrence of large oceanic fronts of satellite-derived sea-surface chlorophyll content (chl a) and temperature (SST). A specific range of surface chl a content (0.11 to 0.39 mg m-3) and a minimum water depth (92 m) were also identified to be important regional criteria. Daily maps were calibrated and evaluated against independent sets of fin whale sightings (presence data only). Specific chl a fronts represented the main predictor of feeding environment; therefore, derived habitat is a potential, rather than effective, habitat, but is functionally linked to a proxy of its resource (chl a production of fronts). The model performs well, with 80% of the presence data <9.7 km from the predicted potential habitat. The computed monthly, seasonal and annual maps of potential feeding habitat from 2000 to 2010 correlate, for the most part, with current knowledge on fin whale ecology. Overall, fin whale potential habitat occurs frequently during summer in dynamic areas of the general circulation, and is substantially more spread over the basin in winter. However, the results also displayed high year-to-year variations (40 to 50%), which are essential to consider when assessing migration patterns and recommending protection and conservation measures. © Inter-Research 2012. Source
Carpinelli E.,Information and Research on Cetaceans |
Carpinelli E.,Tethys Research Institute |
Carpinelli E.,University of Pavia |
Gauffier P.,Information and Research on Cetaceans |
And 12 more authors.
Aquatic Conservation: Marine and Freshwater Ecosystems | Year: 2014
The Mediterranean sperm whale sub-population is considered 'Endangered' by both ACCOBAMS and the IUCN. Conservation policies require protected species populations to be monitored, but the distribution and movements of sperm whales across the Mediterranean Sea are still poorly understood. To provide insight into sperm whale movements, the photo-identification catalogue from the Strait of Gibraltar was compared with seven other collections: (a) the North Atlantic and Mediterranean Sperm Whale Catalogue (NAMSC), and with photo-identification catalogues from (b) the Alboran Sea, Spain, (c) the Balearic Islands, Spain, (d) the Corso-Provençal Basin, France, (e) the Western Ligurian Sea, Italy, (f) the Tyrrhenian Sea, Italy, and (g) the Hellenic Trench, Greece. Of 47 sperm whales identified in the Strait of Gibraltar between 1999 and 2011 a total of 15 animals (32%) were photographically recaptured in other sectors of the western Mediterranean Sea in different years. None of the Strait of Gibraltar sperm whales were resighted in Atlantic waters or in the eastern Mediterranean basin. These results indicate long-range movements of the species throughout the whole western Mediterranean Sea, with a maximum straight-line distance of about 1600km. The absence of any photographic recaptures between the Mediterranean Sea and the North Atlantic Ocean supports the genetic evidence of an isolated sub-population within the Mediterranean Sea. Long-term photo-identification efforts and data sharing between institutions should be further encouraged to provide basic information necessary for the implementation of effective sperm whale conservation measures in the whole basin. Copyright © 2014 John Wiley & Sons, Ltd. 24 S1 July 2014 10.1002/aqc.2446 Supplement Article Research Articles Copyright © 2014 John Wiley & Sons, Ltd. Source
Campana I.,University of Tuscia |
Crosti R.,European Commission - Joint Research Center Ispra |
Angeletti D.,University of Tuscia |
Carosso L.,University of Pisa |
And 8 more authors.
Marine Environmental Research | Year: 2015
Maritime traffic is one of many anthropogenic pressures threatening the marine environment. This study was specifically designed to investigate the relationship between vessels presence and cetacean sightings in the high sea areas of the Western Mediterranean Sea region. We recorded and compared the total number of vessels in the presence and absence of cetacean sightings using data gathered during the summer season (2009-2013) along six fixed transects repeatedly surveyed. In locations with cetacean sightings (N = 2667), nautical traffic was significantly lower, by 20%, compared to random locations where no sightings occurred (N = 1226): all cetacean species, except bottlenose dolphin, were generally observed in locations with lower vessel abundance. In different areas the species showed variable results likely influenced by a combination of biological and local environmental factors. The approach of this research helped create, for the first time, a wide vision of the different responses of animals towards a common pressure. © 2015 Elsevier Ltd. Source