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Francesca Capezzuto
Ruolo
Ricercatore a tempo determinato - tipo A
Organizzazione
Università degli Studi di Bari Aldo Moro
Dipartimento
DIPARTIMENTO DI BIOLOGIA
Area Scientifica
AREA 05 - Scienze biologiche
Settore Scientifico Disciplinare
BIO/07 - Ecologia
Settore ERC 1° livello
Non Disponibile
Settore ERC 2° livello
Non Disponibile
Settore ERC 3° livello
Non Disponibile
Age and growth of L. crocodilus (Osteichthyes, Myctophidae) were estimated using otoliths by direct and backcalculation methods. Data were collected in the Ionian Sea during nine seasonal trawl surveys carried out between 2000 and 2004. The maximum age identified was 8 years. The age-length keys obtained by the two different methods provided comparable results
The Santa Maria di Leuca (SML) cold-water coral (CWC) province is a proposed priority conservation area according to several conservation initiatives in the Mediterranean Sea. Part of it is a Fisheries Restricted Area (FRA). Anthropogenic impacts due to fishing on this FRA were investigated using a towed camera system during 2005. The geographic distribution of fishing effort in the SML CWC province was examined through an observers' program of longline and trawl fishing activities during 2009 and 2010 and Vessel Monitoring by satellite System (VMS) data from 2008 to 2013. Using the video system, it was possible to observe evidence of impacts in the FRA due to longlines, proved by remains of lines on the bottoms and/or entangled in corals, and those due to trawl nets, proved by trawl door scars on the bottom. The application of Generalized Liner Models indicates that the impacts due to longline were significantly related to a geographic site characterized by carbonate mounds while those from trawl net were significantly related to the soft bottoms, consisting of bioturbated fine-grained sediments. The presence of waste of various types was also observed in the FRA; plastic was the most widespread waste and was significantly related to a macrohabitat characterized by the presence of corals. The geographic distribution of fishing effort for each type of fishing were rather superimposed in the two years of the observers' program and six years of VMS data with a significantly greater fishing effort outside the FRA than inside this area. The trawlers generally fished on the muddy bottoms of the upper and middle slope within the SML CWC province and near and inside the northward limit of the FRA. The longliners fished mainly on the shelf in north and off the FRA. The coral by-catch was only recorded during 2009 in 26% of the trawl hauls. No coral by-catch was recorded from longlining in either year. The catches from longlining mainly consisted of Chelidonichthys lucerna, Merluccius merluccius and Conger conger while those from trawling mostly consisted of Aristeus antennatus, Aristaeomorpha foliacea and M. merluccius. The information collected during the observers' program and VMS data indicated greater impact due to trawling than longlining. The conservation and effective management of this vulnerable marine ecosystem remain difficult.
Using longline a comparison of H. dactylopterus abundance and length distribution between coral and non coral habitats inside the Santa Maria di Leuca coral province is provided
Using a towed camera system a total of 422 individuals belonging to 62 taxa, of which 33 identified at species level, were counted in the Santa Maria di Leuca (SML) coral province, updating the knowledge on the biodiversity of this area and on the depth records of several species. The presence of coral mounds mostly in the north-eastern sector of the SML coral province seems to influence the large scale distribution of the deep-sea benthopelagic fauna, playing a role of attraction-refuge with respect to the barren muddy bottoms where fishing occurs in northward areas. Indeed, 38% of the species identified are of commercial interest and all are accidentally captured by trawling and/or longline outside the SML coral area. The Multiple Correspondence Analysis identified three main species/taxa groups: one including species/taxa more strictly linked to the bottom, resting and/or moving on the seabed, often sheltering and feeding; another group mostly consisting of species/taxa quietly swimming in the water column and mostly observed on rugged bottoms; and a third group made up of species/taxa actively swimming and hovering near the seabed. The behavioural patterns mostly related to activity and position of the fauna seem to determine their small-scale distribution while the effects of different benthic macrohabitats appear to be less important. Even less the depth within the bathymetric range examined. The behavioral patterns reflect aspects of the species life strategies, revealing common features in phylogenetically and ecologically distant species. Typical pelagic species, such as squids, were mostly observed to swim in the water column near to the bottom. Small individuals of Lepidopus caudatus, searching for food in very deep sediment, revealed a completely different behaviour from that known in adults. Aristeus antennatus was mostly observed in sediment-dominated bottoms in different positions and activities. The teleost Helicolenus dactylopterus exhibited a clear behavioural pattern of resting on seabed in different macrohabitats. The golden shrimp Plesionika martia and the fish Pagellus bogaraveo were mostly observed quietly swimming and hovering respectively near seabed. These two species seem to be influenced by the presence of corals.
Canyons play a fundamental role in enhancing the abundance and diversity of marine organisms through the transport of organic matter and food resources, the presence of complex physical habitats and the absence of trawl fishing. During four baited lander deployments carried out in the Bari Canyon (Southern Adriatic Sea, Central Mediterranean), at depths of 443–788 m, about 43 h of video records were taken, for a total of 619,200 video frames. A total of 12 benthopelagic fish species (five chondrichthyes and seven osteichthyes) were identified. The blackspot seabream (Pagellus bogaraveo) was the most often observed fish species. The depth of 787 m represents a new depth record for this fish in the Adriatic Sea. Groups of up to 40 individuals of P. bogaraveo were attracted to the bait and were shown in single frames. The individuals were observed both exploring the area and feeding actively on the bait. The European conger (Conger conger) was recorded at each deployment. Clear scavenger behaviour was also observed in this teleost fish and in the shark Etmopterus spinax. The shark species Centrophorus granulosus and Hexanchus griseus, which are considered ‘vulnerable’ on the published IUCN Mediterranean Regional Red List, were also recorded but, although attracted by the bait, they were never seen feeding on it. Other fish species, harvested on fishing grounds, such as Merluccius merluccius, Helicolenus dactylopterus and Polyprion americanus, were also recorded. This study represents the first in situ documentation, at very low impact, of the fish fauna in the Bari Canyon, providing new insights into its small scale distribution and behaviour, the first in situ direct observation of the variable feeding behaviour of P. bogaraveo and its gregarious habits, as well as indicating that this canyon could act as a refuge area for species that are vulnerable to fishing on the open slope.
This paper reports the first finding of the sea pen Protoptilum carpenteri Kölliker, 1872 in theMediterranean Sea. A total of three colonies were collected in 2010 with an epibenthic sledge, and one colony in 2013 with a bottom-trawl net, in the Santa Maria di Leuca (SML) coral province in the Ionian Sea. The main anatomical features and taxonomic characteristics are reported and discussed in order to update the knowledge of this species. A description of morphologies and dimensions of the sclerites, taken from different parts of the colony, is reported. A comparison with Atlantic records is given and discussed.
Occurrence of juveniles of Scyliorhinus canicula and Mustelus mustelus was investigated as part of trawl surveys carried out from 1994 to 2009 in the North-western Ionian Sea. Two main finding areas were observed for juveniles of S. canicula and one of M. mustelus
Occurrence and behaviour of Paromola cuvieri (Crustacea, Decapoda) were recorded by means of the MEMO lander equipped with two digital cameras and deployed in the cold-water coral community of the Santa Maria di Leuca (Mediterranean Sea). A total of 14 individuals were observed at depths between 547 and 648 m; 10 in the coral habitat on coral mounds and 4 off the coral habitat on muddybottoms. Thirteen specimens recorded were females, one male and all were shown to scavenge the bait. All the specimens carried a sponge on their exoskeleton using the fifth pereiopods. The specimens were distinguishable by the size and shape of the carried sponge. The present observations demonstrate both passive covering behaviour and active behaviour of discouraging approach and attack from competitors or predators, respectively. This study represents the first in situ documentation of Paromola cuvieri behaviour interacting with other deep-sea species in the Mediterranean Sea.
The presence of the basking shark Cetorhinus maximus (Lamniformes: Cetorhinidae) in the central-eastern Mediterranean Sea has been documented by means of 15 sightings and two accidental catches which occurred from February 2011 to January 2014 in the northwestern Ionian and southern Adriatic Sea. Specimens were observed exhibiting typical feeding behaviour, swimming slowly on the surface, during each sighting. In the case of the accidental catches, the basking shark specimens were released still alive by local fishermen. The observed specimens measured between 4 and 9 m in total length (TL). The sightings could be due to an increase in effort in the monitoring of the species occurring in the Mediterranean Sea as a consequence of a rise interest in the conservation of threatened species.
Blackbelly rosefish Helicolenus dactylopterus is a zygoparous fish whose males are equipped with the copulating organ named urogenital papilla (UP). This study deals with the morphology and the glycoconjugate pattern of the UP epidermis, which is the male tissue interacting with the female internal body during copulation. The carbohydrate content was studied by means of conventional and lectin histochemistry. The epidermis was shown to be a stratified cuboidal epithelium and to exhibit characteristic intraepithelial pits in the apical zone. The mucous cells are scattered in the epidermis. The epidermal cell layers and their thickness as well as the size of mucous cells varied along the UP. Conventional histochemistry showed that the mucous cells contained i) only neutral glycoproteins in the basal zone; ii) both neutral and acidic nonsulphated glycans as well as only acidic non-sulphated or sulphated glycoconjugates in the intermediate zone; iii) neutral and sulphated glycoconjugates in the apical zone. The mucous cells in the basal region expressed O-linked (mucin type) glycans terminating with αGalNAc, Galβ1,3GalNAc which could be α2,3-linked to sialic acid, and high mannose type N-linked glycans terminating with fucose, lactosamine, and sialic α2,6-linked to galactose/N-acetylgalactosamine; terminal Gal and terminal/internal GlcNAc were also found. The mucous cells in the intermediate zone lacked Galβ1,3GalNAc and showed less terminal α2,3-linked sialic acid, lactosamine, fucose, galactose, and internal N-acetylglucosamine residues. In the apical region, mucous cells only exhibited O-glycans terminating with GalNAc and N-acetylglucosamine. The demonstrated region-specific differences in the UP skin provide new insights into the reproductive biology of fishes with internal fertilization.
The spatio-temporal distribution pattern of Munida rutllanti in the north-western Ionian Sea has been studied. Data were collected during 14 experimental trawl surveys conducted from 1997 to 2010 as part of the international MEDITS project. The hauls were carried out during day-light hours between depths of 10 and 800 m in the spring season. A progressive increase in the abun¬dance index (N/km2) of M. rutllanti was observed from 2000 to 2008, then a sharp decrease was shown in the last two years. The greatest and lowest abundance indices were observed in the Apulian and central Calabrian sub-areas, respectively. The species was collected between 107 and 795 m in depth, with a significant increase and decrease over time in the maximum and minimum depth of finding, respectively. A highly significant increase over time in the mean carapace length was also observed in the whole study area. The widespread occurrence and increasing abundance of this species in the Ionian Sea could be related to the increase in temperature and the variation in hydrographic conditions which occurred in the Ionian basin during the EMT-BiOS phenomenon.
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