Dekapodni rakovi u zaljevu Argolikos (istočni dio Sredozemnog mora, središnji dio Egejskog mora)

The study presents the biomass, the abundance and the depth distribution of the decapod crustaceans in Argolikos Gulf (Central Aegean Sea) from data collected in trawl surveys carried out throughout 2008. This work is the first systematic work in this important Greek area and will support the knowledge for understanding the decapods stocks’ fishery in the above area. A total of 28 species of decapod crustaceans was identified from a total of 42 hauls made in three depth zones (50-100 m, 100-200 m, 500-600 m). Among decapods recorded were 6 Dendrobranchiata (5 Penaeoidea, 1 Sergestoidea), 22 Pleocyemata (9 Brachyura, 8 Caridea, 2 Anomura, 1 Palinurid, 1 Astacideum, 1 Stenopodidea). The most abundant commercial species found in both shallower depth zones (50-100 m, 100-200 m ) was Parapenaeus longirostris while in the deepest one (500-600 m) Aristaeomorpha foliacea was the most numerous. Some new depth distribution records for the Eastern Mediterranean were obtained for some few species.U ovom radu su prikazani biomasa, abundancija i dubinska raspodjela dekapodnih rakova u Argolikos zaljevu (središnji dio Egejskog mora) dobiveni iz podataka prikupljenih povlačnim alatima tijekom 2008. godine. Ovaj rad je prvi sustavni rad, iz ovog važnog grčkog područja, koji donosi saznanja za bolje razumijevanje dekapodnih zaliha. Ustanovljeno je 28 vrsta dekapodnih rakova tijekom 42 koćarska potega na tri dubine (50-100 m, 100-200 m, 500-600 m). Zabilježene su slijedeće vrste dekapodnih rakova: 6 Dendrobranchiata (5 Penaeoidea, 1 Sergestoidea), 22 Pleocyemata (9 Brachyura, 8 Caridea, 2 Anomura, 1 Palinurid, 1 stacideum, 1 Stenopodidea). Najbrojnija komercijalna vrsta koja je pronađena u obje pliće zone (50-100 m, 100-200 m) je P. longirostris, dok je u najdubljoj zoni (500-600 m) bio najbrojniji A. foliacea. Tijekom istraživanja u istočnom Sredozemnom moru su ustanovljeni novi nalazi o raspodjeli nekih vrsta prema dubini

Zapažanja o ponašanju odraslih lubina Dicentrarchus labrax (L. 1758) tijekom hranidbe u zatočeništvu i konceptualizacija za uzgoj vrsta

This paper presents experimental results on the voracity and foraging behaviour of the European sea bass, Dicentrarchus labrax adults kept in captivity fed a commercial broodstock feed suitable for the species. The results show that the species is a very aggressive predator even after 2 decades of captivity actively competing for food. The primary sensory stimulus to attack the food particles is vision. The number of food particles in the water also affect the foraging behaviour of the fish. As the number of pellets offered simultaneously increases from 10 to 50, so increases the number of missed attempts to consume the particles as well as the number of collisions between individuals attempting to consume the same particle. However, when the number of pellets is more than 30, the dispersion caused by the fish movements is greater and the fish are able to consume more pellets in one pass and therefore, the amount of pellets is consumed sooner. Conceptualising our results for the Mediterranean farming of the sea bass, we consider that its foraging behaviour as described in his paper should be considered as an indicator of good welfare of the farmed fish. In addition, the species foraging behaviour may have important undesirable side effects such as the infliction of trauma due to biting between fish during collisions as well as the loss of food particles through the cage nets during feeding due to the turbulence the fish create by attacking the food particles and missing.U radu su opisani eksperimentalni rezultati o proždrljivosti i grabežljivosti lubina, Dicentrarchus labrax hranjenog komercijalnom hranom u zatočeništvu. Rezultati ukazuju da je lubin vrlo agresivni predator unatoč 20-godišnjem zatočeništvu. Primarni osjetilni senzor za napad na čestice hrane je vid. Broj čestica hrane u vodi također utječe na potragu za česticama hrane. S porastom broja peleta od 10 do 50, povećava se i broj neuspješnih pokušaja uzimanja hrane, kao i broj sudara riba u bazenu. Međutim, kada je broj peleta hrane veći od trideset, raspršenost hrane u bazenu uslijed kretanja riba je veća, zbog čega ribe mogu u jednom napadu pojesti više peleta hrane, te se hrana brže pojede. Primjena ovih rezultata u mediteranskom uzgoju lubina može se razmatrati s aspekta dobrobiti uzgajanih riba. Opisano ponašanje riba kod hranidbe može imati i važne nepoželjne učinke, kao što su ozljede uslijed međusobnih ugriza i sudara, kao i do gubitka hrane radi propadanja kroz kavez uslijed turbulencije koju ribe stvaraju napadima i promašajima čestica hrane

Population Characteristics of the Upper Infralittoral Sea Urchin Arbacia lixula (Linnaeus, 1758) in Eastern Mediterranean (Central Greece): An Indicator Species for Coastal Water Quality

The black sea urchin (Arbacia lixula, Linnaeus, 1758) is a non-edible marine echinoderm of high ecological importance with the potential to affect marine ecological communities. A. lixula were sampled monthly for one year from the supralittoral fringe at two locations in the Pagasitikos Gulf, in the north-western Aegean Sea. Morphometric characteristics exhibited significant spatiotemporal variation. The population in closer proximity to treated sewage effluent outflow exhibited significantly higher biometric relationships resulting in possible improved physiological conditions. Spatial distribution exhibited a clumped pattern of dispersion, consisting of predominantly six age classes. The dominant cohort was the four-year age class, comprising 31.2% of the total population. Significant negative allometric relationships were exhibited between all morphometric characteristics. The maximum approximate age of the total A. lixula population was estimated at 15.27 years. The von Bertalanffy growth equation for the entire population was estimated as: test diameter = 62.881×1−e−0.196×Age+1.147. The gonadosomatic index indicated a seasonal cycle with a peak in late spring. The approximate age of sexual maturity was estimated at 4.45 years. We observed a significantly higher number of females than expected at the site in closer proximity to the treated sewage effluents (32% of total female number)

Population Characteristics of the Mid-Littoral Chthamalid Barnacle C. stellatus (Poli, 1791) in Eastern Mediterranean (Central Greece)

Barnacles are key space-occupiers in rocky shore communities on European coasts. Barnacles of the species Chthamalus stellatus (Poli, 1791) were collected between June 2014 and May 2015 from two sites, two stations per each site with varying degree of exposure to wave action and anthropogenic pressure (trampling), in the Eastern Mediterranean (Pagasitikos Gulf, Central Greece). This study addresses a knowledge gap in population characteristics of C. stellatus populations in the Eastern Mediterranean, assessing population structure and allometric relationships. Patterns of distribution and abundance (density and percentage cover) were studied both temporally (seasonally) and spatially (water level and site). Morphometric characteristics exhibited spatiotemporal variation. Population density was significantly higher at the site with higher wave exposure. The population cover exhibited high levels of similarity among shore levels, both spatially and temporally. Spatial distribution exhibited a clumped pattern of dispersion in autumn, winter, and spring, mainly in the sheltered site. Six dominant age groups were identified, with the dominant cohort in the third-year class. Significant negative allometric relationships were exhibited between all morphometric characteristics. Differences in growth patterns among populations were indicated, with a higher rate of growth at the site of lower wave exposure

Rare Earths as Authenticity Markers for the Discrimination of Greek and Turkish Pistachios Using Elemental Metabolomics and Chemometrics

Pistachios are a nutritionally beneficial food source widely consumed all over the world. Pistachios exhibit high content of antioxidants, vitamins and other beneficial micronutrients, including nutrient elements and rare earth elements (REEs). Considering that the concentration of REEs depends on the climate and soil characteristics that vary among different geographical regions, REEs could constitute markers responsible for the geographical discrimination of this nut type. In this study, Greek pistachios with a protected designation of origin (PDO) label from Aegina Island and Fthiotida and Turkish pistachios from Adana were analyzed with inductively coupled plasma mass spectrometry (ICP-MS) to assess their REE profile. La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb were determined and quantified. The quantification results were further analyzed using the main effect plot, permutational analysis of variance (PERMANOVA), nonmetric multidimensional scaling (nMDS), principal component analysis (PCA) and hierarchical clustering (HCA) to investigate the similarities between the pistachios. A decision tree (DT) was developed for the classification of pistachios according to their geographical origin proving to be a promising and reliable tool for verifying the authenticity of food products on the basis of their REE profile

A Rapid HPLC-UV Protocol Coupled to Chemometric Analysis for the Determination of the Major Phenolic Constituents and Tocopherol Content in Almonds and the Discrimination of the Geographical Origin

Reversed phase-high-pressure liquid chromatographic methodologies equipped with UV detector (RP-HPLC-UV) were developed for the determination of phenolic compounds and tocopherols in almonds. Nineteen samples of Texas almonds originating from USA and Greece were analyzed and 7 phenolic acids, 7 flavonoids, and tocopherols (−α, −β + γ) were determined. The analytical methodologies were validated and presented excellent linearity (r2 > 0.99), high recoveries over the range between 83.1 (syringic acid) to 95.5% (ferulic acid) for within-day assay (n = 6), and between 90.2 (diosmin) to 103.4% (rosmarinic acid) for between-day assay (n = 3 × 3), for phenolic compounds, and between 95.1 and 100.4% for within-day assay (n = 6), and between 93.2–96.2% for between-day assay (n = 3 × 3) for tocopherols. The analytes were further quantified, and the results were analyzed by principal component analysis (PCA), and agglomerative hierarchical clustering (AHC) to investigate potential differences between the bioactive content of almonds and the geographical origin. A decision tree (DT) was developed for the prediction of the geographical origin of almonds proposing a characteristic marker with a concentration threshold, proving to be a promising and reliable tool for the guarantee of the authenticity of the almonds

Occurrence of the Invasive Crab Species Callinectes sapidus Rathbun, 1896, in NW Greece

The present work aims to review and describe the current status of the invasive species Callinectes sapidus Rathbun, 1896, along the Ionian coastal zone of Greece and to assess its invasive potential. Blue crab has a long invasion history in the Mediterranean Sea, but the available data on the species occurrence in the Ionian sub-region are scarce and fragmented. The proximity of most of the estuaries and lagoons to local ports and to the shipping routes, as well as the swimming/dispersal ability of the adults of the species, indicate that range expansion will likely continue. The invasiveness risk of the species in the region was estimated with the use of a decision support tool (Marine Invertebrate Invasiveness Screening Kit, version 1.19). The observed impacts are discussed, along with urgent mitigation priorities. Measures to limit the expansion of this invasive species may include the effective management of ballast waters and the targeted increase of fishing pressure on C. sapidus populations. The importance of ballast water management is further highlighted by the existence of numerous ports with the capacity to serve ships with ballast tanks in close proximity to the recipient ecosystems. Moreover, the Ionian Sea, which connects the Adriatic Sea to the rest of the Mediterranean, is a significant shipping route for the local, regional, and international seaborne trade

Rare Earths as Authenticity Markers for the Discrimination of Greek and Turkish Pistachios Using Elemental Metabolomics and Chemometrics

Pistachios are a nutritionally beneficial food source widely consumed all over the world. Pistachios exhibit high content of antioxidants, vitamins and other beneficial micronutrients, including nutrient elements and rare earth elements (REEs). Considering that the concentration of REEs depends on the climate and soil characteristics that vary among different geographical regions, REEs could constitute markers responsible for the geographical discrimination of this nut type. In this study, Greek pistachios with a protected designation of origin (PDO) label from Aegina Island and Fthiotida and Turkish pistachios from Adana were analyzed with inductively coupled plasma mass spectrometry (ICP-MS) to assess their REE profile. La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb were determined and quantified. The quantification results were further analyzed using the main effect plot, permutational analysis of variance (PERMANOVA), nonmetric multidimensional scaling (nMDS), principal component analysis (PCA) and hierarchical clustering (HCA) to investigate the similarities between the pistachios. A decision tree (DT) was developed for the classification of pistachios according to their geographical origin proving to be a promising and reliable tool for verifying the authenticity of food products on the basis of their REE profile

Ecological Assessment of Fishery Communities in an Otter-Trawl-Restricted, Semi-Enclosed Gulf in Greece

A fishery-independent survey with a commercial bottom otter trawl was conducted in the Pagasitikos Gulf, a semi-enclosed, trawl-restricted gulf in Greece. The study aimed to ecologically assess the fishery communities that are experiencing a decline in fishery landings. Twelve hauls of 30 min duration each were conducted in the eastern, western, and central parts of the gulf at depths between 62 and 97 m. In total, 57 species were captured, with the highest species number recorded in the west (35 species), followed by the center (32 species) and east (29 species). The highest numerical abundance was recorded at the center, followed by the east and west, with an opposing trend exhibited for biomass; however, GLM detected no significant spatial differences (in area or depth) or interaction. Ecological indices exhibited significantly lower values in the west–east area comparison. Linear Discriminant Analysis, mMDS, and hierarchical clustering indicated the presence of two main groups (east and west), with PERMANOVA showing a significant difference in the demersal communities among the identified groups. The results indicated moderately disturbed demersal communities and an increasing level of disturbance from east to west. Considering the economic value of Pagasitikos to the local fishing community, additional fishery management measures are deemed necessary to protect the fishery resources and mitigate the potential risks of overexploitation