Search results for "Study"
showing 10 items of 15483 documents
Diet and trophic niche of the invasive signal crayfish in the first invaded Italian stream ecosystem.
2021
The occurrence of the signal crayfsh Pacifastacus leniusculus in the Valla Stream was the frst established population of this invasive species recorded in an Italian stream ecosystem. We evaluated the seasonality of diet and trophic niche of invasive signal crayfsh in order to estimate the ecological role and efects on native communities of the stream ecosystem. We studied the diferences in food source use between sexes, life stages and seasons using carbon and nitrogen stable isotope analyses. To supplement stable isotope analyses, we evaluated food source usage using traditional stomach content analysis. We tested the hypothesis that juveniles have a diferent diet, showing diferent trophi…
Spatial genetic structure in the saddled sea bream (Oblada melanura [Linnaeus, 1758]) suggests multi-scaled patterns of connectivity between protecte…
2016
Marine protected areas (MPAs) and networks of MPAs are advocated worldwide for the achievement of marine conservation objectives. Although the knowledge about population connectivity is considered fundamental for the optimal design of MPAs and networks, the amount of information available for the Mediterranean Sea is currently scarce. We investigated the genetic structure of the saddled sea bream (Oblada melanura) and the level of genetic connectivity between protected and unprotected locations, using a set of 11 microsatellite loci. Spatial patterns of population differentiation were assessed locally (50–100 km) and regionally (500–1000 km), considering three MPAs of the Western Mediterran…
Interbreeding between local and translocated populations of a cleaner fish in an experimental mesocosm predicts risk of disrupted local adaptation
2019
Source at https://doi.org/10.1002/ece3.5246. Translocation of organisms within or outside its native range carries the risk of modifying the community of the recipient ecosystems and induces gene flow between locally adapted populations or closely related species. In this study, we evaluated the genetic consequences of large‐scale translocation of cleaner wrasses that has become a common practice within the salmon aquaculture industry in northern Europe to combat sea lice infestation. A major concern with this practice is the potential for hybridization of escaped organisms with the local, recipient wrasse population, and thus potentially introduce exogenous alleles and breaking down coadap…
Nicodemia madagascariensis(Lam.) R. Parker (Family Scrophulariaceae), a casual alien plant new to Italy
2016
In this note the authors report the first case of naturalization of the Malagasy smoke bush within Italian territory. Along with a description of the abiotic and biotic characteristics of the invaded site, the current demographic and dynamic trends of the detected population by means of growth-ring analysis was also assessed. Moreover, an overview on the history of its introduction in Europe is provided, underlining the key role played by the Mediterranean cities with respect to the acclimatization and spread of alien tropical and subtropical plants. Due to its low frequency under cultivation, the Malagasy smoke bush should not behave as an invader in the future; on the other hand, its abil…
The challenge of habitat modelling for threatened low density species using heterogeneous data: The case of Cuvier’s beaked whales in the Mediterrane…
2018
We are grateful to the ACCOBAMS Secretariat for their support in this work, including a small grant for the analysis. The Mediterranean population of Cuvieŕs beaked whale (Ziphius cavirostris), a deep-diving cetacean, is genetically distinct from the Atlantic, and subject to a number of conservation threats, in particular underwater noise. It is also cryptic at the surface and relatively rare, so obtain robust knowledge on distribution and abundance presents unique challenges. Here we use multiplatform and multiyear survey data to analyse the distribution and abundance of this species across the Mediterranean Sea. We use a novel approach combining heterogeneous data gathered with different …
The Mediterranean Sea hosts endemic haplotypes and a distinct population of the dolphinfish Coryphaena hippurus Linnaeus, 1758 (Perciformes, Coryphae…
2017
Abstract The dolphinfish, Coryphaena hippurus Linnaeus, 1758, is an important target species for Mediterranean artisanal, recreational and commercial fisheries but to date only scarce genetic data are available for its Mediterranean population(s). The genetic variation of Mediterranean dolphinfishes was thus investigated through the sequencing of fragments of the cytochrome c oxidase subunit 1 (COI) gene and the NADH dehydrogenase subunit 1 (ND1) mitochondrial DNA markers with the explicit aims of (i) testing for significant genetic differentiation of the Mediterranean vs . non-Mediterranean populations of the species, and (ii) investigating the possible presence of molecular structuring wi…
Staying alive on an active volcano: 80 years population dynamics of Cytisus aeolicus (Fabaceae) from Stromboli (Aeolian Islands, Italy)
2020
Abstract Cytisus aeolicus is a narrow endemic species restricted to the Aeolian archipelago (SE Tyrrhenian Sea, Italy) and it is one of the most evolutionarily isolated plants in the Mediterranean flora. Historical and literature data suggest that both metapopulations and isolated individuals of C. aeolicus are gradually shrinking. Field investigations and drone images demonstrate that the C. aeolicus metapopulation from Stromboli experienced a strikingly fast increase during the last decades. As of 2019, more than 7000 ± 3000 mature individuals occur on Stromboli, i.e. 14 to 20 times more than those counted during the last census, 25 years ago. The diachronic analysis of aerial photos conc…
A new rare species of Oedipoda Latreille, 1829 (Orthoptera: Acrididae) from South Italy
2019
Oedipoda cynthiae n. sp. (Orthoptera: Acrididae: Oedipodinae) is described from Apulia (South Italy). In the past, the same population here considered had been assigned to O. miniata and later to O. charpentieri. Morphological features, biogeographical considerations, and a preliminary molecular analysis confirm that this population must be assigned to a new species, which is described and illustrated here.
Exploring connectivity between spawning and nursery areas ofMullus barbatus(L., 1758) in the Mediterranean through a dispersal model
2017
Connectivity between spawning and nursery areas plays a major role in determining the spatial structure of fish populations and the boundaries of stock units. Here, the potential effects of surface current on a red mullet population in the Central Mediterranean were simulated using a physical oceanographic model. Red mullet larvae were represented as Lagrangian drifters released in known spawning areas of the Strait of Sicily (SoS), which represents one of the most productive demersal fishing-grounds of the Mediterranean. To consider the effect of inter-annual variability of oceanographic patterns, numerical simulations were performed for the spawning seasons from 1999 to 2012. The main goa…
Nanism (dwarfism) in fish: a comparison between red mullet Mullus barbatus from the southeastern and the central Mediterranean
2007
The gradient of environmental conditions from west to east in the Mediterranean results in very low primary productivity in the eastern area of this sea. This impoverishment is expressed also in higher trophic levels and has been accounted for by several faunistic phenomena. One of these is 'Levantine nanism' (dwarfism); this is characterized by smaller body size of specimens in the Levantine basin compared with conspecifics in the western Mediterranean. Nanism has been hypothesized for various taxonomic groups in the Mediterranean, but no quantitative study has yet been carried out to confirm it. In the present study male and female red mullet Mullus barbatus from trawl surveys carried out…