158 research outputs found
The Presence of the invasive Lionfish Pterois miles in the Mediterranean Sea
Here we report the occurrence of Pterois miles in the Mediterranean Sea, based on the capture of two specimens along the coast of Lebanon. Previously, only one record of the species from the Mediterranean Sea had been documented. The new records highlight the arrival of new propagules of P. miles, more than two decades later, hinting to a future potential invasion of the Mediterranean Sea
Fish diversity associated with gas platforms: Evaluation of two underwater visual census techniques
Fish assemblages associated with offshore platforms were surveyed using two underwater visual census techniques: strip
transects and mobile point counts. Data were collected from four depth ranges at three platforms off Crotone, Italy (Ionian Sea).
A total of 25 fish species belonging to 12 families were recorded for the three platforms. Significant differences between
sampling methods and depth were observed in the fish assemblage structure, species richness and fish abundance. The mean
number of species recorded with the strip transect method was always greater than that obtained with mobile point counts, whilst
the opposite pattern was observed for mean abundances. Gregarious species such as Boops boops, Chromis chromis, Anthias
anthias and Oblada melanura were responsible for most of the differences in the assemblage structure. According to our results,
both methods allowed us to observe species that are not usually caught by means of fishing gear. When both census techniques
are used, they provide complementary information about the fish assemblages strictly associated with the platform structures
First record of the twobar sea bream Acanthopagrus bifasciatus (Teleostei: Sparidae) in the Mediterranean Sea
In September 2010, one specimen of the twobar seabream Acanthopagrus bifasciatus was recorded for the first time in the Mediterranean Sea, off the Islands of Zembra (Gulf of Tunisi: 37°07â03ââN; 10°48â35ââE). This species could have entered the Mediterranean via the Suez Canal or alternatively by unintentional human transport
Video monitoring of Sparidae temporal rhythms: three-year study by OBSEA cabled observatory
The abundance and composition of fish assemblages varies at different temporal scales as a product of diel and annual rhythms. In this study, we used a video-wired observatory (OBSEA, www.obsea.es) to monitor annual rhythms in a coastal fish assemblage with a 3-year data set (2012-2014). The photographs were acquired at 30 min frequency. Five species of the family Sparidae were studied (i.e. Dentex dentex, Diplodus sargus, Diplodus vulgaris, Diplodus annularis and Diplodus puntazzo) together with water temperature and daylength. The results of the annual rhythmicity analysis indicated that most of the peaks of abundance occured in the autumn months. Results suggest differentially temporal use of the reproductive or trophic niche.Peer ReviewedPostprint (published version
Tracking the invasion of Hemiramphus far and Saurida undosquamis along the southern Mediterranean coasts: A Local Ecological Knowledge study
Local Ecological Knowledge of 92 professional fishers from Tunisia and Libya was used to investigate on the occurrence and establishment of the exotic Hemiramphus far and Saurida undosquamis along the southern Mediterranean coasts. According to fishermanâs knowledge, H. far and S. undosquamis appeared in Libya, in 1980 and 1989 respectively. In Tunisia these species were observed afterwards, in 2004 and 2007. Currently both H. far and S. undosquamis result to be well distributed and established, along the entire surveyed area, from Tubrouk (eastern Libya) to Tabarka (western Tunisia). A statistical analysis of the qualitative trends in abundance perceived by the respondents show that both species have significantly increased in abundance in Tunisia. In Libya an increase of the abundance of H. far was also apparent during the first decade of the 21st century but the current abundance of S. undosquamis resulted to be stable at the level of occasional captures. Given the lack of regular environmental monitoring programmes in the area, these findings provide information that could not have been obtained otherwise. Besides improving our understanding on the status and chronology of these invasions, this approach highlights the value of fishermanâs knowledge to reconstruct ecological process in the course of rapid historical modifications
Marine alien species in Italy: A contribution to the implementation of descriptor D2 of the Marine Strategy Framework Directive
A re-examination of marine alien species or Non Indigenous Species (NIS) reported in Italian Seas, until December 2018, is provided, focusing on establishment success, year of first record, origin, potential invasiveness, and likely pathways, in particular. Furthermore, their distribution is assessed according to the marine subregions outlined by the European Union (EU) Marine Strategy Framework Directive: Adriatic Sea (ADRIA), Ionian Sea and Central Mediterranean Sea (CMED), and Western Mediterranean Sea (WMED). In Italy, 265 NIS have been detected with the highest number of species being recorded in the CMED (154 species) and the WMED (151 species) subregions, followed by the ADRIA (143) subregion. Most of these species were recorded in more than one subregion. One hundred and eighty (180 or 68%) NIS have established stable populations in Italian Seas among which 26 have exhibited invasive traits. As regards the taxa involved, Macrophyta rank first with 65 taxa. Fifty-five of them are established in at least one subregion, mostly in the ADRIA and the CMED. Crustacea rank second with 48 taxa, followed by Polychaeta with 43 taxa, Mollusca with 29 taxa, and Fishes with 28 taxa, which were mainly reported from the CMED. In the period 2012-2017, 44 new alien species were recorded, resulting in approximately one new entry every two months. Approximately half of the NIS (~52%) recorded in Italy have most likely arrived through the transport-stowaway pathway related to shipping traffic (~28% as biofoulers, ~22% in ballast waters, and ~2% as hitchhikers). The second most common pathway is the unaided movement with currents (~19%), followed by the transport-contaminant on farmed shellfishes pathway (~18%). "Unaided" is the most common pathway for alien Fishes, especially in the CMED; escapes from confinement account for ~3% and release in nature for ~2%. The present NIS distribution hotspots for new introductions were defined at the first recipient area/location in Italy. In the ADRIA, the hotspot, Venice, accounts for the highest number of alien taxa introduced in Italy, with 50 newly recorded taxa. In the CMED subregion, the hotspots of introduction are the Taranto and Catania Gulfs, hosting 21 first records each. The Strait of Sicily represents a crossroad between alien taxa from the Atlantic Ocean and the Indo-Pacific area. In the WMED, bioinvasion hotspots include the Gulfs of Naples, Genoa and Livorno. This review can serve as an updated baseline for future coordination and harmonization of monitoring initiatives under international, EU and regional policies, for the compilation of new data from established monitoring programs, and for rapid assessment surveys
A metaâanalysis of fish behavioural reaction to underwater human presence
WOS:000483722600001In an increasingly anthropic world, humans have profound impacts on the distribution and behaviour of marine fishes. The increased human presence has modified fishes' antipredator behavioural responses, and consequently flight decisions, as a function of their changed perceptions of risk. Understanding how fish react to human presence can help identify the most vulnerable functional groups/species and estimate impacts caused by human disturbance. Shoal and body size are known to influence fish flight initiation distance (FID; the distance between the predator and prey when the prey begins to escape); however, few studies attempt to test the moderators of these relationships. Here, we present a comprehensive meta-analysis evaluating FID of fish in response to human presence. Specifically, we investigated six candidate moderators that could influence the relationship between FID with shoal and body size. Our results showed that individual fish size was strongly and positively correlated with FID and the most important moderator that explained the variance in individual body size-FID relationship was shoaling behaviour. However, and somehow surprisingly, we detected no significant relationship between shoal size and FID. We discuss how these results can inform the development of fish conservation strategies and ultimately assist in the management of marine protected areas
Annual rhythms of temporal niche partitioning in the Sparidae family are correlated to different environmental variables
none11siopenSbragaglia, Valerio; Nuñez, JesĂșs D.; Dominoni, Davide; Coco, Salvatore; Fanelli, Emanuela; Azzurro, Ernesto; Marini, Simone; Nogueras, Marc; Ponti, Massimo; del Rio Fernandez, Joaquin; Aguzzi, JacopoSbragaglia, Valerio; Nuñez, JesĂșs D.; Dominoni, Davide; Coco, Salvatore; Fanelli, Emanuela; Azzurro, Ernesto; Marini, Simone; Nogueras, Marc; Ponti, Massimo; del Rio Fernandez, Joaquin; Aguzzi, Jacop
First records of Sphyraena chrysotaenia (Klunzinger, 1884) and Diadema setosum (Leske, 1778) in the Marine Protected Area of Zakynthos Island (Ionian Sea, Greece)
In 2021, three specimens of the Lessepsian yellowstripe barracuda Sphyraena chrysotaenia and eight specimens of the Indo-Pacific needle-spined sea urchin Diadema setosum were recorded along the coasts of Zakynthos Island, some within the Marine Protected Area
A lionfish (Pterois miles) invasion has begun in the Mediterranean Sea
Until now, few sightings of the alien lionfish Pterois miles have been reported in the Mediterranean and it was questionable whether the species could invade this region like it has in the western Atlantic. Here, we present evidence from divers and fishermen that lionfish have recently increased in abundance and within a year colonised almost the entire south eastern coast of Cyprus, likely due to sea surface warming. At least 23 different fish are reported of which 6 were removed. Groups of lionfish exhibiting mating behaviour have been noted for the first time in the Mediterranean. Managers need this information and should alert stakeholders to the potential ecological and socio-economic impacts that may arise from a lionfish invasion. Actions could involve incentives to engage divers and fishermen in lionfish removal programmes, as these have worked well at shallow depths in the Caribbean. Given that the Suez Canal has recently been widened and deepened, measures will need to be put in place to help prevent further invasion
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