Ishrana trlje kamenjarke, Mullus surmuletus u istočnom Jadranskom moru

Feeding habits of the striped red mullet, Mullus surmutetus in the eastern Adriatic Sea were investigated. Stomach contents of 203 specimens (11.5 - 32.9 cm TL) collected by bottom trawling were analyzed. Commonly accepted procedures were followed during the diet composition inspection and standard keys were used for food items determination. Examinations showed that 39 identified prey taxa belong to 11 major systematic groups: Crustacea, Gastropoda, Bivalvia, Pisces, Cnidaria, Echinodermata, Polychaeta, Nematoda, Bryozoa, Algae and Rhizaria. The predominant and preferred prey category was decapod crustaceans within all size categories and only in the largest individuals, the dominance of Bivalvia followed by Polychaeta and Crustacea were found. The largest individuals also showed more variety in consumption of different prey categories and a higher mean number of prey items in comparison with smaller fish. No significant differences in prey foraging between males and females ((p>0.05)) and regarding to season ((p>0.05)) were found. Feeding on such wide spectra of prey without significant variations regarding to sex and season suggests that the striped red mullets are able to adapt to shifts in spatio-temporal variations in the abundance of potential prey. Presence of detritus in the digestive tracts is highly related to its foraging behaviour on muddy detritic bottoms.Istraživana je ishrana trlje kamenjarke, Mullus surmuletus u istočnom dijelu Jadrankog mora. Analiziran je sadržaj želudca 203 jedinke (11.5 – 32.9 cm TL) prikupljenih pridnenom povlačnom mrežom koćom. Opće su prihvaćene metode i ključevi za determinaciju korišteni za određivanje sastava ishrane i determinaciju plijena. Istraživanjem je određeno 39 identificiranih vrsta plijena koji spadaju u 11 glavnih skupina: rakovi, puževi, školjkaši, ribe, žarnjaci, bodljikaši, mnogočetinaši, oblići, mahovnjaci, alge i krednjaci. Dominantna i poželjna kategorija plijena bili su dekapodni rakovi unutar svih veličinskih kategorija, dok je samo kod najvećih jedinki pronađena dominantnost školjkaša, a slijede ih mnogočetinaši i rakovi. Najveće jedinke također su pokazale veću raznolikost u konzumaciji različitih vrsta plijena i prosječno veći broj jedinki plijena u odnosu na manje ribe. Nije pronađena značajna razlika u ishrani između mužjaka i ženki ((p>0.05)) i s obzirom na sezonu Istraživana je ishrana trlje kamenjarke, Mullus surmuletus u istočnom dijelu Jadrankog mora. Analiziran je sadržaj želudca 203 jedinke (11.5 – 32.9 cm TL) prikupljenih pridnenom povlačnom mrežom koćom. Opće su prihvaćene metode i ključevi za determinaciju korišteni za određivanje sastava ishrane i determinaciju plijena. Istraživanjem je određeno 39 identificiranih vrsta plijena koji spadaju u 11 glavnih skupina: rakovi, puževi, školjkaši, ribe, žarnjaci, bodljikaši, mnogočetinaši, oblići, mahovnjaci, alge i krednjaci. Dominantna i poželjna kategorija plijena bili su dekapodni rakovi unutar svih veličinskih kategorija, dok je samo kod najvećih jedinki pronađena dominantnost školjkaša, a slijede ih mnogočetinaši i rakovi. Najveće jedinke također su pokazale veću raznolikost u konzumaciji različitih vrsta plijena i prosječno veći broj jedinki plijena u odnosu na manje ribe. Nije pronađena značajna razlika u ishrani između mužjaka i ženki ((p>0.05)) i s obzirom na sezonu ((p>0.05)). Hranjenje širokim spektrom plijena bez značajnih varijacija u vezi sa spolom i sezonom sugerira da se trlja od kamena može prilagoditi pomacima u prostorno-vremenskim varijacijama obilja potencijalnog plijena. Prisutnost detritusa u probavnom traktu povezana je s načinom hranjenja istraživane vrste na muljevitim detritičnim dnima. Hranjenje širokim spektrom plijena bez značajnih varijacija u vezi sa spolom i sezonom sugerira da se trlja od kamena može prilagoditi pomacima u prostorno-vremenskim varijacijama obilja potencijalnog plijena. Prisutnost detritusa u probavnom traktu povezana je s načinom hranjenja istraživane vrste na muljevitim detritičnim dnima

Novi nalaz plavog trkača, Caranx crysos (Mitchill, 1815), u Jadranskom moru

A specimen of blue runner (Caranx crysos) was caught in a gillnet by a fisherman in the waters of the Neretva River estuary, near Ploče. Main morphometric and meristic counts were taken. The total length (LT) of C. crysos was 18.5 cm and it weighed 91.47 g. This is the second record of C. crysos in the Adriatic Sea.Primjerak plavog trkača (Caranx crysos) je ulovljen mrežom prosticom na području ušća rijeke Neretve u blizini grada Ploče. Izmjerene su glavne morfometrijske i merističke mjere. Ukupna dužina (Lt) primjerka C. crysos iznosi 18,5 cm, a masa 91,47 g. Ovo je drugi nalaz vrste C. crysos u Jadranskom moru

“New Alien Mediterranean Biodiversity Records” (March 2021)

This article includes twenty (20) new records of alien and cryptogenic species in the Mediterranean Sea, belonging to six (6) Phyla (Rhodophyta, Tracheophyta, Mollusca, Arthropoda, Bryozoa, and Chordata) distributed from the Eastern Mediterranean to the Sea of Alboran. The records are reported from nine (9) countries and can be classified into two categories: new records for the Mediterranean Sea and new records of non-indigenous species expanding within the Mediterranean Sea. The first category includes the gastropod Turbo radiatus from Lebanon coasts, the portunid crab Charybdis (Charybdis) natator from Tunis southern lagoon, the mollusc Thuridilla mazda from South Spain, and the nudibranch Okenia picoensis from the Alboran coasts of Spain and from Malta. The second category includes the bivalve Nudiscintilla cf. glabra from the Aegean coast of Turkey, the rhodophyte Colaconema codicola from the North Aegean coasts of Greece, the naked band gaper Champsodon nudivittis from the Sea of Marmara, Turkey. Also, the brachyuran Gonioinfradens giardi from the Greek Ionian waters, the codlet Bregmaceros nectabanus from the Croatian coasts of the Adriatic Sea, and the bryozoan Arbopercula tenella and copepod Parvocalanus crassirostris both from the Gulf of Trieste, Slovenian and Italian coasts, respectively. New records were also reported for the ascidian Distaplia bermudensis from brackish the Gulf of Naples, Italy, the damselfish Abudefduf cf. saxatilis and the seagrass Halophila stipulacea from Sardinia, Tyrrhenian Sea, and for the fish Paranthias furcifer from the harbour of Almeria, Alboran Sea, Spain. Through these records, an understanding of the expanding mechanisms and processes and, if possible, the development of mitigation measures within the region will be further facilitated

Workshop to review and progress the reported lists of eu msfd descriptor 3 ( (WKD3LISTS)

info:eu-repo/semantics/publishedVersio

ClimateFish: A Collaborative Database to Track the Abundance of Selected Coastal Fish Species as Candidate Indicators of Climate Change in the Mediterranean Sea

Under the effects of global warming, many animals and plants are undergoing rapid distribution shifts. These changes can be particularly rapid in marine fishes, and many species have responded markedly to recent increases in sea temperature. ClimateFish is an open-access database, which collates abundance data for 7 Mediterranean indigenous and 8 non-indigenous fishes, proposed as candidate indicators of climate change. These species have been selected by a network of Mediterranean scientists based on their wide distribution, responsiveness to temperature conditions and easy identification. Data are periodically collected according to a standard visual census protocol in four different depth layers. At present, the database collates data on a total number of 101'771 observed individuals belonging to the 15 target species. Counts were realized along 3142 transects carried out in 7 Mediterranean countries between 2009 and 2021. This database, associated with climate data, offers new opportunities to investigate spatiotemporal effects of climate change and to test the effectiveness of each selected indicator. Data are available at https://doi.org/10.17882/86784.The Mediterranean ClimateFish initiative was initially conceived by the international basin wide monitoring program CIESM Tropical Signals (funded by the Albert II of Monaco Foundation) and subsequently supported by the Interreg Med Programme (Projects: MPA-ADAPT, grant number 1MED15_3.2_M2_337 and MPA Engage, grant number 5MED18_3.2_M23_007), 85% co funded by the European Regional Development Fund

New Alien Mediterranean Biodiversity Records (March 2021)

This article includes twenty (20) new records of alien and cryptogenic species in the Mediterranean Sea, belonging to six (6) Phyla (Rhodophyta, Tracheophyta, Mollusca, Arthropoda, Bryozoa, and Chordata) distributed from the Eastern Mediterranean to the Sea of Alboran. The records are reported from nine (9) countries and can be classified into two categories: new records for the Mediterranean Sea and new records of non-indigenous species expanding within the Mediterranean Sea. The first category includes the gastropod Turbo radiatus from Lebanon coasts, the portunid crab Charybdis (Charybdis) natator from Tunis southern lagoon, the mollusc Thuridilla mazda from South Spain, and the nudibranch Okenia picoensis from the Alboran coasts of Spain and from Malta. The second category includes the bivalve Nudiscintilla cf. glabra from the Aegean coast of Turkey, the rhodophyte Colaconema codicola from the North Aegean coasts of Greece, the naked band gaper Champsodon nudivittis from the Sea of Marmara, Turkey. Also, the brachyuran Gonioinfradens giardi from the Greek Ionian waters, the codlet Bregmaceros nectabanus from the Croatian coasts of the Adriatic Sea, and the bryozoan Arbopercula tenella and copepod Parvocalanus crassirostris both from the Gulf of Trieste, Slovenian and Italian coasts, respectively. New records were also reported for the ascidian Distaplia bermudensis from brackish the Gulf of Naples, Italy, the damselfish Abudefduf cf. saxatilis and the seagrass Halophila stipulacea from Sardinia, Tyrrhenian Sea, and for the fish Paranthias furcifer from the harbour of Almeria, Alboran Sea, Spain. Through these records, an understanding of the expanding mechanisms and processes and, if possible, the development of mitigation measures within the region will be further facilitated

Dynamics, connectivity and genetic structure of the European lobster Homarus gammarus (Linnaeus, 1758) in the Adriatic Sea

Stanje populacije hlapa (Homarus gammarus) u Jadranskom moru procijenjeno je primjenom metoda ribarstvene biologije i populacijske genetike. Analizom službenih podataka o ulovu hlapa u razdoblju od 2008. do 2017. uočeno je povećanje ulova, ribolovnog napora i ulova po jedinici ribolovnog napora u sjevernom Jadranu, dok je u istom razdoblju zabilježen pozitivni trend izmjerene i modelirane pridnene temperature mora. Utvrđena je značajna povezanost pridnene temperature mora i ulova po jedinici ribolovnog napora u sjevernom i srednjem Jadranu. Najzastupljeniji dužinski razredi hlapa su bili od 80 - 120 mm dužine glavopršnjaka, a jedinke ispod minimalne veličine ulova su činile 52,83 % ukupnog uzorka. Zabilježene su niske vrijednosti ulova po jedinici ribolovnog napora (4,6 - 239 g/vrši) s najvišim vrijednostima u proljeće i ljeto. Manje jedinke hlapa nastanjuju plića staništa i bliže obali, dok se sve veće jedinke pojavljuju dalje od obale. Postoji spolni dimorfizam u rastu hlapa s izraženijim rastom mase za mužjake nego ženke, dok ženke s dužinama glavopršnjaka većim od 80 mm imaju značajno širi abdomen od mužjaka. Prekomjerni izlov, gubitak staništa i druge antropogene aktivnosti nisu značajno utjecale na neutralnu genetičku raznolikost. Ukupna genetička udaljenost je bila niska između istraživanih populacija (FST = 0,0062). Genetička diferencijacija je utvrđena među populacijama iz različitih bazena Sredozemnog mora, dok su populacije iz Jadranskog mora bile panmiktične. Prosječna suvremena efektivna veličina populacije (NE) procijenjena za populacije hlapa se kolebala od 1,560 do 2,094 ovisno o metodi te su najveće vrijednosti zabilježene za populacije sjevernog Jadrana. Procjene stope migracije ukazuju da sjeveroistočna obala Jadranskog mora djeluje kao glavni izvor protoka gena te se genetički materijal može prenijeti od 300 do 600 km ovisno o trajanju pelagične faze ličinke hlapa i dinamici morske vode. Ovo istraživanje predstavlja prvo sveobuhvatno istraživanje stanja populacije hlapa u Jadranskome moru i rezultati ovog istraživanja mogu služiti kao informacije potrebne za održivo i učinkovitije upravljanje ovom ekološki i ekonomski važnom vrstom rakova u Jadranskom moru.Population dynamics of European lobster (Homarus gammarus) in the Adriatic Sea was assessed using various fisheries biology and population genetics methods. The analysis of European lobster official catch data from 2008 to 2017 showed an increase in landings, fishing effort and catch per unit effort in the northern Adriatic. A positive trend of increasing measured and modelled sea bottom temperature was also recorded. A significant correlation between sea bottom temperature and catch per unit effort in the northern and central Adriatic has been established. Dominance of specimens in the 80 - 120 mm carapace length size classes was observed and individuals below the minimum landing size accounted for 52.83 % of the total sample. Low values of catch per unit effort were recorded, ranging from 4.6 to 239 g/pot with the highest values observed in spring and summer. Smaller individuals inhabit shallower habitats and closer to coast while larger individuals occur farther from coast. Sexual dimorphism in growth was observed with more pronounced increase in weight for males than females, while females have a significantly wider abdomen than males when carapace length exceeds 80 mm. Overfishing, habitat loss and other anthropogenic activities did not significantly affect neutral genetic diversity. The global genetic distance between the studied populations was low (FST = 0.0062). Genetic differentiation was found among populations from different Mediterranean basins, while populations from the Adriatic Sea were panmictic. The average contemporary effective population size (NE) estimated for European lobster populations ranged from 1,560 to 2,094, depending on the method used, with the highest values for populations in the northern Adriatic. Estimates of migration rates indicate that the north-eastern coast of the Adriatic Sea acts as the main source of gene flow, and genetic material can be transferred from 300 to 600 km depending on the pelagic larval duration. This research is the first comprehensive study of the European lobster population status in the Adriatic Sea, the results of which can serve as a basis for sustainable and effective fisheries management of this ecologically and economically important crustacean species

Dynamics, connectivity and genetic structure of the European lobster Homarus gammarus (Linnaeus, 1758) in the Adriatic Sea

Stanje populacije hlapa (Homarus gammarus) u Jadranskom moru procijenjeno je primjenom metoda ribarstvene biologije i populacijske genetike. Analizom službenih podataka o ulovu hlapa u razdoblju od 2008. do 2017. uočeno je povećanje ulova, ribolovnog napora i ulova po jedinici ribolovnog napora u sjevernom Jadranu, dok je u istom razdoblju zabilježen pozitivni trend izmjerene i modelirane pridnene temperature mora. Utvrđena je značajna povezanost pridnene temperature mora i ulova po jedinici ribolovnog napora u sjevernom i srednjem Jadranu. Najzastupljeniji dužinski razredi hlapa su bili od 80 - 120 mm dužine glavopršnjaka, a jedinke ispod minimalne veličine ulova su činile 52,83 % ukupnog uzorka. Zabilježene su niske vrijednosti ulova po jedinici ribolovnog napora (4,6 - 239 g/vrši) s najvišim vrijednostima u proljeće i ljeto. Manje jedinke hlapa nastanjuju plića staništa i bliže obali, dok se sve veće jedinke pojavljuju dalje od obale. Postoji spolni dimorfizam u rastu hlapa s izraženijim rastom mase za mužjake nego ženke, dok ženke s dužinama glavopršnjaka većim od 80 mm imaju značajno širi abdomen od mužjaka. Prekomjerni izlov, gubitak staništa i druge antropogene aktivnosti nisu značajno utjecale na neutralnu genetičku raznolikost. Ukupna genetička udaljenost je bila niska između istraživanih populacija (FST = 0,0062). Genetička diferencijacija je utvrđena među populacijama iz različitih bazena Sredozemnog mora, dok su populacije iz Jadranskog mora bile panmiktične. Prosječna suvremena efektivna veličina populacije (NE) procijenjena za populacije hlapa se kolebala od 1,560 do 2,094 ovisno o metodi te su najveće vrijednosti zabilježene za populacije sjevernog Jadrana. Procjene stope migracije ukazuju da sjeveroistočna obala Jadranskog mora djeluje kao glavni izvor protoka gena te se genetički materijal može prenijeti od 300 do 600 km ovisno o trajanju pelagične faze ličinke hlapa i dinamici morske vode. Ovo istraživanje predstavlja prvo sveobuhvatno istraživanje stanja populacije hlapa u Jadranskome moru i rezultati ovog istraživanja mogu služiti kao informacije potrebne za održivo i učinkovitije upravljanje ovom ekološki i ekonomski važnom vrstom rakova u Jadranskom moru.Population dynamics of European lobster (Homarus gammarus) in the Adriatic Sea was assessed using various fisheries biology and population genetics methods. The analysis of European lobster official catch data from 2008 to 2017 showed an increase in landings, fishing effort and catch per unit effort in the northern Adriatic. A positive trend of increasing measured and modelled sea bottom temperature was also recorded. A significant correlation between sea bottom temperature and catch per unit effort in the northern and central Adriatic has been established. Dominance of specimens in the 80 - 120 mm carapace length size classes was observed and individuals below the minimum landing size accounted for 52.83 % of the total sample. Low values of catch per unit effort were recorded, ranging from 4.6 to 239 g/pot with the highest values observed in spring and summer. Smaller individuals inhabit shallower habitats and closer to coast while larger individuals occur farther from coast. Sexual dimorphism in growth was observed with more pronounced increase in weight for males than females, while females have a significantly wider abdomen than males when carapace length exceeds 80 mm. Overfishing, habitat loss and other anthropogenic activities did not significantly affect neutral genetic diversity. The global genetic distance between the studied populations was low (FST = 0.0062). Genetic differentiation was found among populations from different Mediterranean basins, while populations from the Adriatic Sea were panmictic. The average contemporary effective population size (NE) estimated for European lobster populations ranged from 1,560 to 2,094, depending on the method used, with the highest values for populations in the northern Adriatic. Estimates of migration rates indicate that the north-eastern coast of the Adriatic Sea acts as the main source of gene flow, and genetic material can be transferred from 300 to 600 km depending on the pelagic larval duration. This research is the first comprehensive study of the European lobster population status in the Adriatic Sea, the results of which can serve as a basis for sustainable and effective fisheries management of this ecologically and economically important crustacean species