Waters of Ischia and Ventotene Important Marine Mammal Area - IMMA Description The area, located in the Tyrrhenian Sea (Italy), Area Size is characterized by the presence of complex 1,067 km2 and varied geological structures, with some submarine canyons. The boundary of this Qualifying Species and Criteria candidate area includes the Cuma's canyon Common dolphin - Delphinus delphis system and the deep valley between Ischia Criterion A; C (i, ii) and Ventotene Islands. The variations in Common bottlenose dolphin - bottom topography and bathymetry influence Tursiops truncatus oceanographic processes that concentrate Criterion A; C (i, ii) nutrients and structure prey availability Fin whale - Balaenoptera physalus vertically in the water column (e.g. upwelling Criterion A; C (ii); phenomena), consequently attracting key species in the pelagic trophic web like Marine Mammal Diversity Meganictiphanes norvegica (Mussi et al., [Physeter macrocephalus, Grampus griseus, 1999, 2014). Depth range covers Stenella coeruleoalba] approximately 1000 m isobath. The area is Summary entirely under the Italian jurisdiction. Vulnerable Mediterranean fin whales Based on published (Mussi and Miragliuolo, (Balaenoptera physalus), Vulnerable 2003; Mussi et al., 2004; Pace et al., 2012) and common bottlenose dolphins (Tursiops truncatus) and Endangered common unpublished data by Oceanomare Delphis dolphins (Delphinus delphis) have shown Onlus regarding marine mammals in the area, regular presence around the waters of 7 cetacean species have been recorded in the Ischia and the Ventotene Islands, within the area. Information on common dolphin, Tyrrhenian Sea. The complex topography of bottlenose dolphin and fin whale in this IMMA canyon systems contributes to factors which is based on long-time series data collected by shape the species’ presence and Oceanomare Delphis. A total of 1,366 daily distribution. Oceanographic upwelling visual and acoustic surveys were conducted in promotes primary production leading to an 2000-2016, during which about 58,100 km of abundance of krill, Meganyctiphanes track line were completed in 10,649 hours of norvegica, prey for fin whales seasonally occurring in the area. effort. There were 63 encounters with common dolphins. Encounters and movements were mainly located north of Ischia Island, with different patterns observed over the years (Pace et al., 2012, 2015, 2016). The region corresponds to the central heads of Cuma and Punta Cornacchia canyons, within a wide range of depth and middle-high slope. The encounter rate showed an overall value of 0.118 groups/100 km, with a significant steady Authority classified the Mediterranean decline between 2000 and 2016. bottlenose dolphins as ‘Vulnerable’ according to the criteria A2cde and based on a There were 91 encounters with bottlenose suspected population decline of at least 30% dolphin. Encounters and movements were over the last 60 years (Bearzi et al., 2012). principally located in the coastal waters north Ischia Island and over the central heads of the Cuma’s submarine canyon. There were sightings of the species in deeper waters, far from shore sites, clearly related to the Cuma's canyons system (Mussi and Miragliuolo, 2003; Mussi et al., 2004; Pace et al., 2012). There were 35 encounters with fin whales, principally located NW, W and SW of Ischia Island (over the central heads of the Cuma’s submarine canyon, the large, deep valley between Ischia and Ventotene Islands, and Distribution of the common dolphin sightings around the Punta Imperatore Canyon located SW Ischia Island (Oceanomare Delphis Onlus, Ischia. While in the past a strong relationship unpublished). with the Cuma’s canyons system was observed (Mussi et al., 1999), in the last decade the degree of association involves also the south-west sighting areas. Sightings occurred mostly in spring-summer. Criterion A - Species or Population Vulnerability Density map (Kernel) of the bottlenose dolphin sightings around Ischia island (Oceanomare Delphis Mediterranean common dolphins are Onlus, unpublished). genetically differentiated from those inhabiting the Atlantic Ocean and are subject to several threats including incidental mortality in fishing gear, contaminants, prey depletion, disturbance and climate change (Pace et al., 2016). Declined abundance raised conservation concerns for Mediterranean common dolphin and in 2003 the species was listed as ‘Endangered’ in the IUCN Red List, based on criterion A2, which refers to a 50% or greater decline in abundance over the last three generations, the causes of which ‘may not have ceased or may not be understood or Distribution of the fin whale sightings around Ischia Island (Oceanomare Delphis Onlus, unpublished) may not be reversible’ (Bearzi, 2003). Mediterranean bottlenose dolphins are The resident and genetically isolated genetically differentiated from those population of Mediterranean fin whales, inhabiting the contiguous eastern North presumed to number at most in the low Atlantic Ocean and Scottish waters and are thousands (and possibly in decline), is subject subject to several threats including incidental to several threats including ship strikes, mortality in fishing gear, reduced availability disturbance, noise and chemical contaminants of key prey, disturbance, noise and chemical with several potential negative effects at the contaminants. In 2012, the IUCN Red List population level (Notarbartolo di Sciara, 2016). The Mediterranean sub-population has been listed as ‘Vulnerable’ in the IUCN Red List feed at surface, targeting shoaling fish along according to the followings (Panigada and the head of the Cuma’s canyon (Mussi and Notarbartolo di Sciara, 2012): the Miragliuolo, 2003). The feeding preferences of Mediterranean subpopulation, which is common dolphins in Ischia area are not genetically distinct from fin whales in the entirely known, however, observations of Atlantic, contains fewer than 10,000 mature cooperatively herding of schooling fish (mainly individuals; the subpopulation experiences an the Atlantic saury, Scomberesox saurus, inferred continuing decline in number of European anchovy, Engraulis encrasicolus, and mature individuals; all mature individuals are European pilchard, Sardina pilchardus, as well in one sub-population. as fish tosses, circle formations and synchronous diving suggest coordinated Criterion C: Key Life Cycle feeding strategies. Activities As for bottlenose dolphin, the species was Sub-criterion Ci: Reproductive reported to feed at depth, near rocky banks, Areas and to follow bottom trawlers, as reported in many other Mediterranean sites (Mussi and The proposed area fulfils sub-criterion Ci in Miragliuolo, 2003). Fin whale was observed to being an area where evidences on mating, feed in the area, mainly targeting the breeding and calving is available for both Mediterranean krill Meganictiphanes common and bottlenose dolphins (Mussi and norvegica in spring-summer (Mussi et al., Miragliuolo, 2003; Mussi et al., 2004). 1999, Mussi and Miragliuolo, 2003; Pace et al., Confidence in evidence available is very high 2012). thanks to the published/unpublished data. About 88% of observed common dolphin Supporting Information groups and about 70% of bottlenose dolphin groups included immature individuals, with Bearzi, G. 2003. Delphinus delphis most of these including calves and neonates. (Mediterranean subpopulation). The IUCN Red For both species, each age class was List of Threatened Species 2003: encountered during almost all months and http://dx.doi.org/10.2305/IUCN.UK.2003.RLTS field years; parturition has never been .T41762A10557372.en observed, although it likely occurs given the observations of extremely small individuals Bearzi. G., Fortuna, C., Reeves, R. 2012. (classified as newborns) showing foetal folds Tursiops truncatus (Mediterranean on the flanks and lacking basic motor- subpopulation). The IUCN Red List of coordination skills. The relative frequency of Threatened Species 2012: occurrence of groups containing immature e.T16369383A16369386. animals (in relation to all groups) did not vary http://dx.doi.org/10.2305/IUCN.UK.2012- annually. 1.RLTS.T16369383A16369386.en Criterion C: Key Life Cycle Mussi. B., Miragliuolo, A. 2003. I cetacei della costa nord occidentale dell’isola d’Ischia Activities (canyon di Cuma). In: Ambiente marino e Sub-criterion Cii: Feeding Areas costiero e territorio delle isole Flegree (Ischia, Procida e Vivara – Golfo di Napoli). Risultati di The proposed area fulfils sub-criterion Cii in uno studio multidisciplinare (Gambi MC, De being an area where coastal and pelagic Lauro M, Jannuzzi F, eds). Liguori Editore, feeding events were regularly observed for all Napoli, Italy: pp 213-232. species (Mussi and Miragliuolo, 2003; Mussi et al., 2004; Pace et al., 2012). Confidence in Mussi. B., Miragliuolo, A., De Pippo, T., Gambi, evidence available is very high thanks to the M.C., Chiota, D. 2004. The submarine canyon published/unpublished data. In the area, of Cuma (Southern Tyrrhenian Sea, Italy), a common dolphin was frequently observed to cetacean key area to protect. European Research on Cetaceans 15: 178-182. Pace, D.S., Mussi, B., Vella, A., Vella, J., Frey, S., Bearzi, G., Benamer, I., Benmessaoud, R., Mussi, B., Miragliuolo, A., Monzini, E., Diaz Gannier, A., Genov, T., Gimenez, J., Gonzalvo, Lopez, B., Battaglia, M. 1999. Fin whale J., Kerem, D., Larbi Doukara, K., Milani, C., (Balaenoptera physalus) feeding ground in the Murphy, S., Natoli, A., Pierce, G.J. 2016. Report coastal water
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