Morphometric and meristic characteristics of poor cod, Trisopterus minutus (L. 1758), from the eastern central Adriatic Sea

Background and Purpose: Poor cod, Trisopterus minutus (Linnaeus, 1758) is a gadoid fish, which inhabits the Mediterranean and eastern Atlantic. The aim of present work was to investigate the morphological properties of poor cod in the eastern central Adriatic Sea by analyzing classical morphometric and meristic characteristics, and thereby investigating: a) whether there are morphological differences between males and females; b) the existence of possible homogenous or heterogeneous stock morphology; and c) the changes in morphometric characteristics with increase in body length.Material and methods: Samples of 410 poor cod specimens (209 females, 201 males) were collected by bottom-trawl between 2014 and 2016 from five localities in the eastern central Adriatic Sea. In order to analyze biometry of the species; fifteen morphometric and eight meristic characteristics were measured.Results and Conclusions: Total length of all specimens ranged from 8.8 to 27.1 cm. Morphological differences between males and females was not marked. Biometric analysis of the morphometric and meristic characteristics indicated a homogenous morphology stock of Trisopterus minutus in the Adriatic Sea. Changes in some morphometric characteristics obtained in conjunction with an increase in body length showed that smaller specimens have a longer head, eye diameter, ventral fins and second anal fins than adult specimens. The negative correlation recorded for the maximum and minimum body depth indicated that the body elongated with poor cod growth. Comparison of the meristic characteristics that were published earlier show some differences between the poor cod populations inhabiting the Adriatic, Black Sea and eastern Atlantic.</p

Najnoviji podatci o maksimalnoj zabilježenoj starosti i dužini pirke Serranus scriba (Linnaeus, 1758) u Mediteranu

The present study was undertaken not only to register the new recently noticed maximum age and total length of Serranus scriba (Linnaeus, 1758), contributing to the knowledge of this species in the Mediterranean and Adriatic Sea inclusively. A painted comber specimen of 323 mm of total length and age 16 years was caught during August 2008 in the Lavdra Channel (middle-eastern Adriatic Sea).Jedinka pirke Serranus scriba (Linnaeus, 1758) je ulovljena uz sjeverozapadnu obalu otoka Mala Lavadra (istočni dio srednjeg Jadrana). Totalna dužina tijela kao i starost ulovljene pirke je najveća zabilježena do sada na području njenog rasprostranjenja i iznosila je 323 mm odnosno 16 godina

Species composition, seasonal fluctuations, and residency of inshore fish assemblages in the Pantan estuary of the eastern middle Adriatic

A total of 9434 fishes, mainly juveniles, belonging to 15 families and 42 species were caught at six stations in the Pantan estuary in the eastern mid Adriatic. Using a 50 m beach seine, 1493 specimens of 25 species were caught in summer, 2594 specimens of 26 species in autumn, 3626 of 24 species in winter, and 1721 of 30 species in spring. Seven species comprised 87.8% of the total: Atherina boyeri (33.2%), Pomatoschistus marmoratus (28.1%), Liza aurata (8.3%), Liza ramada (7.1%), Aphanius fasciatus (5.5%), Diplodus annularis (2.9%) and Mugil cephalus (2.6%). An ANOSIM2 test for unreplicated 2-way layouts revealed significant differences in species assemblages among the sites (ρav = 0.385, P = 0.007). Stations with similar hydrographic conditions had similar species richness and assemblages. Statistically significant differences were not noted between seasons (ρav = 0.221, P = 0.057) although some seasonal differences, especially between summer and winter, were observed on nMDS plots. The most important ecological category was planktivorous fishes (39.4%), followed by benthic mesocarnivorous fishes (33.9%), and particulate organic matter feeders (21.3%). Twenty-two species were permanent estuary residents, 14 opportunists, and six transients. This study demonstrates that the Pantan estuary is an important fish nursery habitat that, although small, has great spatial fish diversity and therefore deserves special protection

Poredbena analiza značajki dvaju istraživačkih brodova za obavljanje eho-monitoringa sitne plave ribe

Acoustic surveys in the Adriatic Sea have been performed annually by the research vessels “Dallaporta” and “Bios”, equipped with SIMRAD echo-sounders (EK-500 and EK-60), and working with 38 kHz split-beam transducer (ES38B). Since the vessels have different characteristics and use different pelagic trawls for fish sampling, there is uncertainty regarding the comparability of the results obtained. In order to evaluate comparability of the results, a comparison between research vessels was performed. That included comparisons of vessels’ noise, acoustic data collection, and fish samples composition and size structure analyses. The noise generated by both vessels was sufficiently low to allow a single fish detection up to 200 m depth. Acoustic data collected by the two vessels showed similar trends, no significant differences in average SA-values, and highly significant correlation between SA-values. Therefore, unbiased acoustic data collected by vessels could be combined in future stock assessments. Concerning collection of fish samples, anchovy resulted as the most abundant species in the samples collected by both vessels even if size compositions of anchovy were significantly different.Eho-monitoring u jadranskome moru provodi se jednom godišnje korištenjem istraživačkih brodova “Dallaporta” i “bios”, opremljenih s ehosonderima SIMraD (ek-500 i ek-60), te pretvaračima podijeljenog snopa radnih frekvencija od 38 kHz (eS38b). Budući da ovi straživački brodovi imaju različite značajke, a koriste i različite pelagijske koće za uzorkovanje sitne plave ribe, postoje sumnje glede usporedivosti prikupljenih podataka. S ciljem procjene usporedivosti prikupljenih podataka, napravljena je usporedba u prikupljanju podataka ovim istraživačkim brodovima. Uspoređena je buka pojedinih brodova, prikupljanje akustičkih podataka, te usporedbe prikupljenih uzoraka riba s obzirom na sastav i strukturu uzoraka. utvrđeno je da buka koju proizvode oba broda je dovoljno niska da dozvoljava detekciju pojedinačnih riba do dubine od 200 m. Akustički podaci prikupljeni dvama istraživačim brodovima pokazuju slične trendove, bez značajnih razlika u srednjim Sa-vrijednostima i s vrlo značajnom povezanošću među njima. Potvrđeno je da se budućim procjenama ribljih naselja nepristrani akustički podaci ovih brodova mogu međusobno nadopunjavati. Glede prikupljanja uzoraka riba, došlo se do spoznaje da je inćun bio najzastupljenija vrsta u uzorcima koje su sakupila oba istraživačka broda iako je njihova veličinska struktura bila značajno različita

El gallano, Labrus mixtus (Pisces: Labridae): índices biológicos para documentar la historia vital de la especie y contribuir a su conservación

The cuckoo wrasse, Labrus mixtus, is widely distributed in the moderate warm waters of the Atlantic Ocean, including the Mediterranean and Adriatic Seas. Generally, labrids are small inshore coastal species susceptible to anthropogenic habitat degradation and, although without commercial importance, they make up a significant part of the by-catch and discard. Also, these fishes are intensively caught in recreational and subsistence fisheries. Basic biological information is required for their stock assessment and conservation. Studies of the age, growth, reproduction and feeding of L. mixtus have not been undertaken previously in the Adriatic Sea. The observed maximum age of the cuckoo wrasse was 10 years, although most of the sampled fish were 7 years old. The estimated parameters of the von Bertalanffy growth model suggested that the growth of L. mixtus was relatively fast in the first four years of life. L. mixtus is a protogynous hermaphrodite and sex change occurred at 26 cm, while the greatest increase in gonadosomatic index in April confirmed spring as the spawning period. The cuckoo wrasse is an opportunistic predator, feeding primarily on crustaceans, gastropods and fishes. The information provided on biological indices is necessary for life history pathways and future conservation measures of this population in the Adriatic Sea.El gallano, Labrus mixtus, se halla ampliamente distribuido en las zonas templadas del Océano Atlántico, incluyendo el Mediterráneo y el Mar Negro. En general, los lábridos son especies de pequeño tamaño que habitan en aguas costeras, siendo vulnerables a la degradación antrópica del hábitat y, a pesar de ser comercialmente poco importantes, forman una parte importante de los descartes de la pesca profesional. Estos peces también son intensamente capturados por la pesca recreativa o de subsistencia. Se requiere, pues, una información biológica básica para conocer el estado de los stocks y asegurar su conservación. Los estudios sobre la edad, el crecimiento, la reproducción y la alimentación de L. mixtus no se han realizado hasta ahora en el Adriático. La edad máxima observada en esta especie ha sido de 10 años, si bien la mayoría de los peces capturados se situaba en los 7 años. Los parámetros estimados a partir de la ecuación de crecimiento de Von Bertalanffy sugieren que el crecimiento de L. mixtus es rápido durante los primeros años de vida. L. mixtus es una especie hermafrodita proterogínica y el cambio de sexo se produce a los 26 cm de longitud, mientras que el gran incremento del índice gonadosomático en el mes de abril confirma que el periodo de reproducción se produce durante la primavera. El gallano es un depredador oportunista que se alimenta preferentemente de crustáceos, gasterópodos y peces. La información que se da en este artículo sobre los índices biológicos es necesaria para conocer las características vitales de esta especie y para adoptar futuras medidas de conservación de su población en el Adriático

Prvi nalaz iglice veličanstvene, Tylosurus acus imperialis (Rafinesque, 1810) (Osteichthyes: Belonidae) na području hrvatskog ribolovnog mora

Commercial purse seiner collected one specimen of the agujon needlefish, Tylosurus acus imperialis (Rafinesque, 1810), during its fishing activity on 17 July 2015 in the open sea area out off Mljet island (42º 41.9′ N; 17 º 18.1′ E, depth 120 m). Total length and weight of collected female specimen was 111.4 cm and 2048.11 g, respectively. Although this species was previously recorded exclusively entering the area of southern Adriatic Sea (Montenegro-Budva and Italy- Bari), this was its first appearance in the upper Adriatic and within Croatian fishing grounds.Dana 17. srpnja 2015. godine tijekom ribolovne aktivnosti na području otvorenog mora van otoka Mljeta (42º 41.9′ N; 17 º 18.1′E, na dubini od 120 m) plivarica za sitnu plavu ribu je zabilježila ulov iglice veličanstvene, Tylosurus acus imperialis (Rafinesque, 1810). Ukupna dužina tijela jedinke iznosila je 111,4 cm, dok je masa tijela iste iznosila 2048,11 g. Iako je pojava ove vrste bila zabilježena na području južnog dijela Jadranskog mora (Crna Gora-Budva, Italija-Bari), ovo je prvi nalaz iglice veličanstvene kako u hrvatskom tako i u sjevernom dijelu Jadrana općenito

Poredbena analiza značajki dvaju istraživačkih brodova za obavljanje eho-monitoringa sitne plave ribe

Acoustic surveys in the Adriatic Sea have been performed annually by the research vessels “Dallaporta” and “Bios”, equipped with SIMRAD echo-sounders (EK-500 and EK-60), and working with 38 kHz split-beam transducer (ES38B). Since the vessels have different characteristics and use different pelagic trawls for fish sampling, there is uncertainty regarding the comparability of the results obtained. In order to evaluate comparability of the results, a comparison between research vessels was performed. That included comparisons of vessels’ noise, acoustic data collection, and fish samples composition and size structure analyses. The noise generated by both vessels was sufficiently low to allow a single fish detection up to 200 m depth. Acoustic data collected by the two vessels showed similar trends, no significant differences in average SA-values, and highly significant correlation between SA-values. Therefore, unbiased acoustic data collected by vessels could be combined in future stock assessments. Concerning collection of fish samples, anchovy resulted as the most abundant species in the samples collected by both vessels even if size compositions of anchovy were significantly different.Eho-monitoring u jadranskome moru provodi se jednom godišnje korištenjem istraživačkih brodova “Dallaporta” i “bios”, opremljenih s ehosonderima SIMraD (ek-500 i ek-60), te pretvaračima podijeljenog snopa radnih frekvencija od 38 kHz (eS38b). Budući da ovi straživački brodovi imaju različite značajke, a koriste i različite pelagijske koće za uzorkovanje sitne plave ribe, postoje sumnje glede usporedivosti prikupljenih podataka. S ciljem procjene usporedivosti prikupljenih podataka, napravljena je usporedba u prikupljanju podataka ovim istraživačkim brodovima. Uspoređena je buka pojedinih brodova, prikupljanje akustičkih podataka, te usporedbe prikupljenih uzoraka riba s obzirom na sastav i strukturu uzoraka. utvrđeno je da buka koju proizvode oba broda je dovoljno niska da dozvoljava detekciju pojedinačnih riba do dubine od 200 m. Akustički podaci prikupljeni dvama istraživačim brodovima pokazuju slične trendove, bez značajnih razlika u srednjim Sa-vrijednostima i s vrlo značajnom povezanošću među njima. Potvrđeno je da se budućim procjenama ribljih naselja nepristrani akustički podaci ovih brodova mogu međusobno nadopunjavati. Glede prikupljanja uzoraka riba, došlo se do spoznaje da je inćun bio najzastupljenija vrsta u uzorcima koje su sakupila oba istraživačka broda iako je njihova veličinska struktura bila značajno različita

Infralitoralne zajednice riba na ušću Zrmanje, Jadransko more

The infralittoral fish assemblage was investigated inside the temperate Zrmanja river estuary, Adriatic Sea. The specimens were caught using a beach seine at three stations and four times over the year. A total of 10 035 individuals, belonging to 47 species and to 17 families were represented in the catch, out of these Atherina boyeri (60.3%), Symphodus ocellatus (14.4%) and Pomatoschistus marmoratus (7.5%) were most abundant, comprising 82.2% of the total catch. Marine and estuarine species represented 89.6 and 10.4%, respectively, while freshwater species were not observed in samples. Differences in fish assemblages were observed with respect to sampling dates and stations mostly due to different temporal and spatial distributions of juvenile fish settlers. Juveniles of open sea spawners (L. mormyrus, P. erythrinus) were found with increased distance from the river mouth. As they progressively grow, they disperse throughout the estuary. Juveniles of resident species (Pomatoschistus sp.) stayed closer to the river mouth. Permanent estuary residents comprised 11 species, 33 species were opportunists and the remaining 3 were transients. The data thus show that even in small temperate estuariesthe characteristics of river inflow have the potential to alter spatio-temporal patterns in infralittoral fish assemblages.Infralitoralne zajednice riba su proučavane na području ušća rijeke Zrmanje, u Jadranskom moru. Jedinke su ulovljene malom obalnom mrežom potegačom na tri postaje, u četiri uzorkovanja tijekom jedne godine istraživanja. Ukupno 10 035 jedinki svrstanih u 47 vrsta i 17 porodica, je bilo zastupljeno u uzorku, od čega su Atherina boyeri (60,3%), Symphodus ocellatus (14,4%) i Pomatoschistus marmoratus (7,5%) bile najzastupljenije vrste, sačinjavajući 82,2% od ukupnog uzorka. Prave morske i estuarijske vrste riba su bile zastupljene s 89,6, odnosno s 10,4%, dok slatkovodne ribe nisu uopće ulovljene. Utvrđene su prostorne i vremenske razlike u zajednicama riba zbog različite vremenske i prostorne raspodjele nedoraslih riba. Nedorasle jedinke onih vrsta koje se mrijeste u otvorenom moru (L. mormyrus, P. erythrinus) su nađene s povećanom udaljenošću od samog ušća rijeke. Kako su navedene jedinke rasle, tako smo ih nalazili različito rasprostranjene na širem području ušća. Nedorasle jedinke rezidentnih vrsta (Pomatoschistus sp.) su ulovljene blizu samog ušća. Stalni su estuarijski rezidenti sačinjavali 11 vrsta, 33 vrste su bile oportunisti, a preostale 3 tranzitne vrste. Podaci pokazuju da čak i mali estuariji umjerenih geografskih širina imaju potencijal pojačati prostorno-vremenske razlike u zajednicama infralitoralnih riba