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The sandbar shark (Carcharhinus plumbeus) is considered rare in the Adriatic Sea and the majority of records originate from the northern Adriatic, where a nursery area for this species close to the Po delta system has been repeatedly proposed. This study provides 5 new records and analyses the previously published records of sandbar sharks recorded around the delta of the River Bojana (in Montenegro, in the south-eastern Adriatic). The River Bojana located on the border between Montenegro and Albania, is the second largest river flowing into the Adriatic Sea, where it forms a highly productive ecosystem already known as a local hotspot for smooth-hound sharks (Mustelus spp.). New records of sandbar sharks have emerged as a result of citizen science (a social media survey) and direct reports from fishermen. The total length of C. plumbeus juveniles ranged from approximately 800 mm to 1100 mm, and most (n=5) were caught by set gillnets. The data presented here show that juveniles are consistently present around the estuary and indicate the importance of this fragile estuarine ecosystem for sandbar sharks. Additionally, this study also provides morphometric data collected from a single individual.

The Mediterranean Sea shows a trend of increasing temperature and decreasing productivity from the western to the eastern basin. In this work we investigate whether this trend is reflected in the cephalopod assemblages found throughout the Mediterranean. Data obtained with bottom trawl surveys carried out during the last 22 years by EU Mediterranean countries were used. In addition to analysing spatial differences in cephalopod assemblages, we also analysed putative temporal changes during the last two decades. For this purpose, the basin was spatially divided into bioregions, the trawling grounds were subdivided into depth strata, and the dataset was split into two time series of 11 years each. All analyses were done using PRIMER software. The species richness did not vary with the longitudinal gradient, though in most bioregions it showed a mild decrease with depth before plummeting in the deepest waters. Cluster analysis revealed four different bathymetric assemblages in all bioregions. Despite the contrasting conditions between basins and the claims of biodiversity loss, our study revealed that spatial and temporal differences during the last two decades were restricted to changes in the relative abundance of species from a common pool of species inhabiting the whole Mediterranean. El mar Mediterráneo muestra un patrón de aumento de la temperatura y disminución de la productividad de la cuenca occidental a la oriental. En este trabajo se investiga si este patrón se refleja en las comunidades de cefalópodos que habitan el Mediterráneo. Se utilizaron datos obtenidos en campañas de arrastre de fondo realizadas durante los últimos 22 años por la mayoría de países mediterráneos de la UE. Junto con el análisis de las diferencias espaciales en las comunidades de cefalópodos, también se analizaron cambios temporales durante las dos últimas décadas. Para ello, la cuenca se dividió espacialmente en diferentes bioregiones, mientras que el conjunto de datos se dividió en dos series temporales de 11 años cada una. Todos los análisis se realizaron utilizando el software PRIMER. La riqueza específica no varió con el gradiente longitudinal, aunque en la mayoría de las bioregiones mostró una leve disminución con la profundidad antes de desplomarse en el estrato más profundo. El análisis cluster reveló cuatro comunidades batimétricas diferentes en todas las bioregiones. A pesar de las contrastadas condiciones ambientales entre las cuencas y las afirmaciones de pérdida de biodiversidad, nuestro estudio reveló que las diferencias espaciales y temporales durante las dos últimas décadas se limitaron a cambios en la abundancia relativa de las especies a partir de un conjunto faunístico común que habita todo el Mediterráneo.

The knowledge of small-scale fisheries (SSFs) is important to develop management policies and mitigate the competition for marine resources. However, spatially explicit information is often unavailable at the regional and subregional scale. We designed and tested a novel participatory approach to map the SSF fishing effort using the Mediterranean sea as a case study. We applied the approach in eight countries (Albania, Croatia, Italy, Libya, Malta, Montenegro, Slovenia and Tunisia) characterized by different cultural, social, political and ecological features. The results provided quantitative and spatially explicit information on fishing operations on a fine-scale resolution, contributing to overcome the pragmatic and budgetary constraints that to date have prevented an accurate assessment of SSFs worldwide. This novel participatory approach is inspired by the principles of governance, adaptive management, cross-national cooperation and spatial planning, thus supporting the ecosystem approach to fisheries and has the potential to provide a useful complement to traditional assessments.

Most studies on European hake focus on the recruitment process and nursery areas, whereas the information is comparatively limited on the ecology of the juvenile stage (ca. second year of life)—the one most exploited by the Mediterranean trawl fisheries. Using information of the MEDITS programme, we provide a spatial and temporal assessment of the influence of body size and growth on hake survival from recruits (age 0) to juveniles (age 1), along with the impact of surface temperature and chlorophyll variability. At a biogeographic scale, size-dependent survival is supported, with areas with higher mean length of recruits and juveniles yielding higher survival. A similar pattern was observed at interannual level in some western Mediterranean areas, also mediated by a density-dependent effect on growth. However, the most recurrent inter-annual pattern was a negative effect of size on survival, which could be attributed to potential ontogenetic changes in catchability and underrepresentation of intra-annual recruitment pulses that are seasonally inaccessible to the MEDITS sur- vey. Results also evidence that survival in the Alboran and Adriatic seas is dependent on the primary production variability, and that Corsica and Sardinia could be potential feeding grounds receiving juveniles from neighbouring areas. The present study reveals the importance of size- and growth-dependent survival in the juvenile stage of European hake in the Mediter- ranean Sea., Sí

The main aim of the present study is to increase the knowledge on the seasonal dynamics of the set gears used by Adriatic small-scale fisheries (SSFs) through the collation of data (landings, fishing effort, composition of catches, length-frequency distributions of target species and economic value of landings) on target species,. The study focused on the three set gears mainly used in the basin: gillnets, trammel nets and traps. The results confirmed that SSFs are diverse, complex and dynamic, representing an economic and social engine and providing seafood and employment to local economies. In the Adriatic Sea, SSFs exploit coastal fishing grounds where the seasonal fluctuations of the physical and chemical parameters of the water column strongly influence the occurrence of the different species. Because of this, many different types of set gears are currently used to catch a pool of target species over the year. Fishermen use more than one set gear during the year and tend to increase the fishing effort when the target species concentrate inside the coastal areas during the recruitment or the spawning season. Accordingly, landings reached the highest values during such periods and often include a large portion of juveniles and/or spawners. The study highlighted that the lack of appropriate data and complete statistics is still one of the main constraints for most of the Adriatic coastal countries, as few countries have in place routinely monitoring programs while others are dealing mostly with estimates. These gaps often have the effect of marginalizing and undervaluing the real role of SSFs in a Blue Growth process.

WOS: 000419945400117, PubMed ID: 29330368, Using thirteen microsatellite loci for Mullus barbatus and Mullus surmuletus collected in the Mediterranean Sea, the biogeographic boundaries, genetic distribution among and within basins and the impact of prolonged exploitation in both species were investigated as a basis for understanding their population dynamics and for improving Mullus spp. stock management. Different level of diversity indices among these co-occurring species were obtained, with M. barbatus showing higher allele richness and higher mean observed and expected heterozygosity than M. surmuletus. Reduced contemporary effective population size (Ne) and M-ratio values found in both species likely reflects recent demographic changes, due to a combination of high fishing pressures, habitat fragmentation and naturally occurring fluctuations in population size. Different patterns of genetic connectivity among populations sampled within the Mediterranean were observed for both species. Higher genetic structure was found for M. barbatus as opposed to a more homogenous pattern observed in M. surmuletus samples. Adriatic populations, previously considered panmictic and isolated from other Mediterranean regions, showed geographical partitioning within the basin but also population connectivity with the northern Ionian and Tyrrhenian Seas. Our results highlight the need for temporal sampling in understanding the complex pattern of population connectivity in the Mediterranean, particularly for management purposes., FAO AdriaMed Project within the AdriaMed Working Group on Small Scale Fisheries (SSF), This study was funded by the FAO AdriaMed Project within the AdriaMed Working Group on Small Scale Fisheries (SSF). We warmly thank Dr. Enrico Arneri for supporting our initiative from the very start. We acknowledge our colleagues Laura Perini (ISMAR, Venezia), Ana Neves (Universidade de Lisboa Campo Grande, Portugal), Marilena Donnaloia (COISPA Tecnologia & Ricerca - Stazione Sperimentale per lo Studio delle Risorse del Mare, Bari, Italy), Nir Stern (Tel Aviv University, Israel), Martha Koutsidi and Alexis Lazaris (University of Patras), Charis Charilaou and Ioannis Thasitis (DFMR, Cyprus) and local fishers for their invaluable assistance in collecting samples for genetic analyses. Most of the samples were collected in the framework of the DCF programme (Medits and Biological sampling).

Small-scale fisheries (SSF) in Croatia and Montenegro have a long tradition, similar to those of SSFs in other parts of the coastal Mediterranean. In order to improve fisheries management and save the cultural heritage of fishing traditions on the eastern Adriatic coast, scientists and fisheries managers, from these two countries, made an effort, to gain a better understanding of fishing activities and targeted stocks. This is a complex research topic, due to the high and increasing fishing pressure on marine resources as well as the fact that fisheries management throughout the Mediterranean region remains conventional in its nature. Basic characteristics of SSFs in each country are presented. Specific conclusions related to improvement of coastal resources state in term of sustainable use are suggested together with proposal for additional conservation measures and actively involving fishermen in the management process. Finally, guidelines for future management in terms of monitoring and data collection framework (DCF) are proposed for both countries.

Variation in the diversity of ichthyoplankton was analyzed from samples collected during threeyear cycle in Boka Kotorska Bay. Samples were collected using Calvet (modified PairOVET) plankton net at 18 stations, from July 2006 through January 2009. Families with most numerous species were Engraulidae, Sparidae and Labridae. Investigation shows dominance of anchovy (Engraulis encrasicolus), Mediterranean rainbow wrasse (Coris julis) and annular sea bream (Diplodus annularis) during the summer. During the winter, dominant species were sardine (Sardina pilchardus) and Atlantic mackerel (Scomber scombrus), while during the spring dominant species were anchovy, annular sea bream and white sea bream (Diplodus sargus). Spawning of most pelagic fish species in Adriatic Sea starts in spring, and progress during spring and summer months. Therefore, the highest number of species was found in these months, while the lowest number of species was during autumn and winter surveys. Eggs and larval stages of 35 species was determined, while the diversity analysis showed a significant degree of diversity in certain stations where the sea currents were probably the strongest. Diversity of ichthyoplankton communities was analyzed applying two diversity indices: Shannon index (H’) and Simpson index (D). Diversity analysis was performed for each of the 18 investigated stations during the tree-year research, while influence of environmental factors on presence of some ichthyoplankton species by seasons was tested with Canonical Correspondence Analyses (CCA)., Kolebanja u raznolikosti ihtioplanktona analizirana su na uzorcima prikupljenim tijekom tri godine u Bokokotorskom zaljevu. Uzorci su prikupljeni pomoću Calvet (modificirani PairOVET) planktonske mreže na 18 postaja, od srpnja 2006. do siječnja 2009. Najbrojnije su bile obitelji vrsta Engraulidae, Sparidae i Labridae. Istraživanje pokazuje dominaciju inćuna (Engraulis encrasicolus ),kneza (Coris julis) i špara (Diplodus annularis) tijekom ljeta. Tijekom zime, prevladavajuće vrste su bile srdela (Sardina pilchardus) i skuša ( Scomber scombrus), dok su u proljeće prevladavajuće vrste bili inćun i šarag (Diplodus sargus). Mrijest većine vrsta riba u Jadranu počinje u proljeće, a progresivni napredak se odvija tijekom proljetnih i ljetnih mjeseci. Dakle, najveći broj vrsta je pronađen u proljetnim i ljetnim mjesecima, dok je najmanji broj vrsta pronađen tijekom jesenskih i zimskih istraživanja. Tijekom istraživanja pronađeni su jaja i ličinke 35 vrsta, dok je analiza pokazala značajan stupanj raznolikosti na pojedinim postaja gdje su morske struje vjerojatno najjače. Raznolikost ihtioplanktonske zajednice je analizirana primjenjujući dva indeksa raznolikosti: Shannon indeks (H’) i Simpson indeks (D). Analiza raznolikosti je provedena za svaku od 18 istraživanih postaja tijekom trogodišnjih istraživanja, dok je utjecaj ekoloških čimbenika na prisutnost nekih vrsta po sezonama bio testirana primjenom CCA analize (Canonical Correspondence Analyses).

The first record of the deep-sea species Chtenopteryx sicula is reported from the Adriatic Sea. A total of six specimens of this rare species were caught, with bottom trawl and pelagic trawl nets, in the scope of the Deep Sea Research of the bathyal fauna in the South Adriatic Pit in 2008 and 2010. Specimens were caught at depths down to 1200 m, therefore making it the deepest and northernmost finding of this species in the Mediterranean Sea. The dorsal mantle lengths of analyzed specimens ranged between 21 and 60 mm. Only in females, a visceral photophore on the ventral side of the inc sac was detected. Some new information on morphometric body and beak features was given in the paper, including the description of beak pigmentation. A number of increments in statoliths revealed that individuals were between three and five months old. A positive linear correlation between the length of statoliths and number of increments/age in days was detected. Macroscopic and histological samples of gonads proved that one specimen was sexually mature (August), four specimens were in stages of sexual maturation (May and August) and two were immature (March). The results indicated that the maturation process of the species in the South Adriatic Sea starts in spring and the full sexual maturity is reached during summer.

The first record of the deep-sea species Chtenopteryx sicula is reported from the Adriatic Sea. Atotal of six specimens of this rare species were caught, with bottom trawl and pelagic trawl nets, in the scope of the Deep Sea Research of the bathyal fauna in the South Adriatic Pit in 2008 and 2010. Specimens were caught at depths down to 1200 m, therefore making it the deepest and northernmost finding of this species in the Mediterranean Sea. The dorsal mantle lengths of analyzed specimens ranged between 21 and 60 mm. Only in females, a visceral photophore on the ventral side of the inc sac was detected. Some new information on morphometric body and beak features was given in the paper, including the description of beak pigmentation. A number of increments in statoliths revealed that individuals were between three and five months old. A positive linear correlation between the length of statoliths and number of increments/age in days was detected. Macroscopic and histological samples of gonads proved that one specimen was sexually mature (August), four specimens were in stages of sexual maturation (May and August) and two were immature (March). The results indicated that the maturation process of the species in the South Adriatic Sea starts in spring and the full sexual maturity is reached during summer., U radu su opisani prvi nalazi dubokomorske vrste Chtenopteryx sicula u Jadranskom moru. Pridnenom i pelagičnom mrežom ulovljeno je ukupno šest primjeraka ove rijetke vrste u sklopu istraživanja dubokomorskih zajednica u južnojadranskoj kotlini 2008 i 2010. godine. Primjerci su ulovljeni na dubinama do 1200 m te predstavljaju najdublji i ujedno najsjeverniji nalaz ove vrste u Mediteranu. Dorzalna dužina plašta analiziranih jedinki kretala se od 21 do 60 mm. Samo u ženki nađeni su visceralni fotofori na ventralnoj strani vrećice sa crnilom. U radu su date nove informacije vezane uz obilježja kljuna, uključujući detaljan opis pigmentacije. Broj zona prirasta u statolitima ukazuje na starost jedinki između tri i pet mjeseci. Utvrđena je pozitivna korelacija između dužine statolita i broja zoni prirasta/starosti u danima. Makroskopski i histološki uzorci gonada potvrdili su da je jedna jedinka bila spolno zrela (kolovoz), četiri jedinke su bile u stadiju spolnog sazrijevanja (svibanj i kolovoz), a dvije su bile spolno nezrele (ožujak). Rezultati ukazuju na to da proces spolnog sazrijevanja ove vrste u južnom Jadranu počinje u proljeće, dok se puna spolna zrelost doseže tijekom ljeta.

Daily growth rate of juvenile anchovy, Engraulis encrasicolus (Linnaeus, 1758), was estimated in the south-eastern Adriatic Sea. Samples were taken by a commercial beach seine net and the size range of 100 sampled individuals was 5.0-6.8 cm total length. Age was estimated by counting growth increments of sagittal otoliths, which are formed with daily periodicity. Estimated ages were 41- 90 days and hatch date for each age class was back-calculated from the date of capture. The calculated instantaneous growth rate was 0.41 mm day-1. Fish size at metamorphosis from late larva to juvenile was estimated to 3.2 cm total length. Parameters of the von Bertalanffy’s growth function were L∞ = 10.41 and K = 3.36, Dnevna stopa rasta juvenilnog inćuna, Engraulis encrasicolus (linnaeus, 1758), procijenjena je u jugoistočnom Jadranu. Uzorci su sakupljani komercijalnom obalnom mrežom potegačom, a raspon veličine kod 100 uzorkovanih jedinki iznosio je 5.0-6.8 cm ukupne dužine. dob je procijenjena brojenjem dnevnih naraštajnih prstenova na sagitalnim otolitima. Procijenjena starost kolebala je između 41- 90 dana, a nadnevak izvaljivanja ličinke za svaki starosni razred bio je naknadno izračunat prema datumu ulova. Izračunata trenutna stopa rasta iznosila je 0.41 mm dan -1. Veličina ribe za vrijeme metarmofoze iz kasnog stadija ličinke u juvenilni stadij procijenjena je na 3.2 cm ukupne dužine. Parametri u von Bertalanffy-jevoj jednadžbi rasta bili su L∞ = 10.41 i K = 3.36.