Ecological information regarding trophic patterns and the inherent structure of freshwater aquati... more Ecological information regarding trophic patterns and the inherent structure of freshwater aquatic communities is considered fundamental in ecological research. In this study, the trophic patterns of the Greek freshwater fish fauna, belonging to the Balkan biodiversity hotspot, were investigated, and comparisons of freshwater fish species feeding habits among the Greek freshwater ecoregions were performed. The analyses based on the widely used trophic level index and the available composition feeding datasets, along with the utilization of clustering methods, indicated seven major distinct trophic guilds in the Greek ecoregions. The trophic level of the studied fish species ranged from 2.0 to 4.5, thus being within the expected values for freshwater ecosystems, revealing the presence of both top predators and primary consumers. The highest trophic level values were found in the ecoregions of northern Greece. The results also exhibited considerable predominance of higher-trophic-leve...
International Journal of Fisheries and Aquatic Studies, 2016
Venus verrucosa is an edible bivalve of high commercial value in the area of Thermaikos Gulf, NW ... more Venus verrucosa is an edible bivalve of high commercial value in the area of Thermaikos Gulf, NW Aegean Sea and this study investigates the population structure of the species. In total, 9534 specimens with shell length (L) ranging from 11.84mm to 60.22 mm were monthly sampled at four stations. In the majority of cases, mean L was lower than the minimum landing size of 40mm. The mean abundance of the populations was quite similar in between three of the four stations. In Thermaikos Gulf, V. verrucosa displays isometric growth, with mean b value of 3.0544. The value of L∞ ranged from 60.38mm to 65.63mm, while Κ ranged from 0.57 to 1.40 with these values being higher than those previously reported in the literature. The Condition Index values corresponded to the population’s reproductive activity. A spatial and/or a temporal ban of harvesting the species is suggested for sustainable management of V. verrucosa populations in Thermaikos Gulf.
This study investigates the trophic diversity of fishes living in a meadow of Caulerpa prolifera ... more This study investigates the trophic diversity of fishes living in a meadow of Caulerpa prolifera on a bimonthly basis between May 2006 and April 2007 in a semi-enclosed coastal marine ecosystem of the Mediterranean Sea (Elounda Bay, Crete Island). The study area is shallow and protected from waves, and it is covered by a C. prolifera bed, characterized by high organic input and a highly diverse macrobenthic community. Feeding patterns of the fish, investigated on the basis of stomach content analyses, were described in terms of numerical abundance and frequency of occurrence of prey taxa. A total of 1642 fish individuals, belonging to 17 species, were examined. In total, 45,674 prey individuals were identified belonging to 110 prey taxa, most of which were Malacostraca including their larvae and Copepoda (41,175 individuals identified to 71 taxa). Four different trophic groups were identified: herbivorous, pelagic, benthic (hyperbenthic) and piscivorous. Trophic diversity patterns o...
In this study we present a list of invasive/potential invasive alien species in the East and Sout... more In this study we present a list of invasive/potential invasive alien species in the East and South European Network for Invasive Alien Species (ESENIAS) countries with marine borders. The species were classified according to the existing literature and experts’ judgment, as established, casual, invasive and expected. Finally, factsheets were compiled for ten species of high importance based on their expanding/invading character. Of the 160 species comprising the list, 149 were already present in the ESENIAS countries, while eleven were invasive species either present in the Mediterranean or in other European Seas, likely to be recorded in the ESENIAS countries. The majority of the species were of Red Sea/IndoPacific origin (97 species; 60.6%). Italy, Turkey and Greece were the countries with the highest representation of species (159, 152 and 139 species respectively), due to their extended coastline and the number of scholars working on marine invasive species. The highest number o...
This study presents the diet composition of 43 of some of the most abundant fish species from the... more This study presents the diet composition of 43 of some of the most abundant fish species from the North Aegean Sea, Greece. According to the diet analysis and fractional trophic level previously reported in the literature, 20 of the studied species were omnivores with a preference for animals and the other half were carnivores (15 with preference for fish and Cephalopoda, and seven with preference for fish and Decapoda), whereas Parablennius gattorugine was the only recorded omnivore with a preference for plant material. Finally, according to the results of Schoener’s index, diet overlap between species was recorded in a small number of cases (33 out of the 903 pairs examined). Yet, competition among diet-overlapping species may be minimised by either morphological differentiations and/or habitat segregation.
An up-to-date systematic review and unofficial codification of the national fisheries legislation... more An up-to-date systematic review and unofficial codification of the national fisheries legislation was performed, along with an up-to-date systematic review of environmental, archaeological and maritime legislation, about spatio-temporal restrictions of fishing activities by all fishing gears in the Aegean Sea. Spatio-temporal restrictions established by the European Union and the General Fisheries Commission for the Mediterranean were also reviewed. A database was built, including detailed information on the Fisheries Restricted Areas (FRAs) being identified. All FRAs were mapped, as polygons in Geographic Information System shapefiles. The national fisheries, environmental, archeological and maritime legal framework comprises of 32, 2, 37 and 43 legal acts respectively; EU and GFCM legislation consists of one Regulation and one Recommendation respectively. A total of 511 national (254 of fisheries, 21 of environmental, 85 of archaeological and 151 of the maritime legislation), 6 EU...
The multi-level benefits that marine organisms gain when protected from fishing are well acknowle... more The multi-level benefits that marine organisms gain when protected from fishing are well acknowledged. Here, we investigated the effects of a 40-year trawling ban on the status of targeted and non-targeted marine species within a major fishing ground in the northeastern Mediterranean Sea (Thermaikos Gulf, Aegean Sea). Biomass and somatic length of fish and invertebrates (six commercial and three non-commercial demersal species) were measured in three areas of varying fishing pressure, depending on the temporal and spatial operational regimes of fishing vessels. The positive effects of fishing restrictions on the studied demersal stocks were clearly revealed, as the commercial fish species exhibited higher biomass in the intermediate and low pressure areas, as well as increasing maximum and mean total length (and other length indicators) with decreasing fishing effort. The mean total length of non-commercial species generally did not differ among areas, except for species caught and ...
In this study we updated the previous compilation of the feeding habits and trophic levels (TROPH... more In this study we updated the previous compilation of the feeding habits and trophic levels (TROPHs) of Mediterranean fish. In total, 172 publications were retrieved and analysed. Collected data refer to 146 species, with a TROPH value ranging from 2.00 to 4.54. The analysis of TROPH distribution verified the previously proposed classification of species into functional trophic groups. Overall, information on diet composition exits for 203 fish species out of the >700 fishes from the Mediterranean, a fact clearly showing that feeding habits are understudied despite their importance in ecological applications and fisheries management. More than half (60.6%) of these species are classified as omnivores with preference to animal material, 36.5% are carnivores, 1.9% are omnivores with preference to plants, and two (i.e. Siganus luridus and S. rivulatus) are pure herbivores. Finally, towards the direction of filling in information gaps, recommendations for future research are given.
In this Collective Article on “New Mediterranean Biodiversity Records”, we present additional rec... more In this Collective Article on “New Mediterranean Biodiversity Records”, we present additional records of species found in the Mediterranean Sea. These records refer to eight different countries throughout the northern part of the basin, and include 28 species, belonging to five phyla. The findings per country include the following species: Spain: Callinectes sapidus and Chelidonura fulvipunctata; Monaco: Aplysia dactylomela; Italy: Charybdis (Charybdis) feriata, Carcharodon carcharias, Seriola fasciata, and Siganus rivulatus; Malta: Pomacanthus asfur; Croatia: Lagocephalus sceleratus and Pomadasys incisus; Montenegro: Lagocephalus sceleratus; Greece: Amathia (Zoobotryon) verticillata, Atys cf. macandrewii, Cerithium scabridum, Chama pacifica, Dendostrea cf. folium, Ergalatax junionae, Septifer cumingii, Syphonota geographica, Syrnola fasciata, Oxyurichthys petersi, Scarus ghobban, Scorpaena maderensis, Solea aegyptiaca and Upeneus pori; Turkey: Lobotes surinamensis, Ruvettus pretios...
As part of its policy, Mediterranean Marine Science started from 2014 to publish a new series of ... more As part of its policy, Mediterranean Marine Science started from 2014 to publish a new series of collective article with fisheries-related data from the Mediterranean Sea. In this first collective article we present length frequencies and weight-length relationships for the northern brown shrimp Farfantepenaeus aztecus in the eastern Mediterranean, length-weight relationships for 10 fish species in the North Aegean Sea, the feeding habits for 11 sparid fishes in the North Aegean Sea, a review of the existing literature on the feeding and reproduction of common carp Cyprinus carpio in Anatolia (Turkey) and mouth dimensions and the relationships between mouth area and length for seven freshwater fishes from Lake Volvi (Northern Greece).
Ecological information regarding trophic patterns and the inherent structure of freshwater aquati... more Ecological information regarding trophic patterns and the inherent structure of freshwater aquatic communities is considered fundamental in ecological research. In this study, the trophic patterns of the Greek freshwater fish fauna, belonging to the Balkan biodiversity hotspot, were investigated, and comparisons of freshwater fish species feeding habits among the Greek freshwater ecoregions were performed. The analyses based on the widely used trophic level index and the available composition feeding datasets, along with the utilization of clustering methods, indicated seven major distinct trophic guilds in the Greek ecoregions. The trophic level of the studied fish species ranged from 2.0 to 4.5, thus being within the expected values for freshwater ecosystems, revealing the presence of both top predators and primary consumers. The highest trophic level values were found in the ecoregions of northern Greece. The results also exhibited considerable predominance of higher-trophic-leve...
International Journal of Fisheries and Aquatic Studies, 2016
Venus verrucosa is an edible bivalve of high commercial value in the area of Thermaikos Gulf, NW ... more Venus verrucosa is an edible bivalve of high commercial value in the area of Thermaikos Gulf, NW Aegean Sea and this study investigates the population structure of the species. In total, 9534 specimens with shell length (L) ranging from 11.84mm to 60.22 mm were monthly sampled at four stations. In the majority of cases, mean L was lower than the minimum landing size of 40mm. The mean abundance of the populations was quite similar in between three of the four stations. In Thermaikos Gulf, V. verrucosa displays isometric growth, with mean b value of 3.0544. The value of L∞ ranged from 60.38mm to 65.63mm, while Κ ranged from 0.57 to 1.40 with these values being higher than those previously reported in the literature. The Condition Index values corresponded to the population’s reproductive activity. A spatial and/or a temporal ban of harvesting the species is suggested for sustainable management of V. verrucosa populations in Thermaikos Gulf.
This study investigates the trophic diversity of fishes living in a meadow of Caulerpa prolifera ... more This study investigates the trophic diversity of fishes living in a meadow of Caulerpa prolifera on a bimonthly basis between May 2006 and April 2007 in a semi-enclosed coastal marine ecosystem of the Mediterranean Sea (Elounda Bay, Crete Island). The study area is shallow and protected from waves, and it is covered by a C. prolifera bed, characterized by high organic input and a highly diverse macrobenthic community. Feeding patterns of the fish, investigated on the basis of stomach content analyses, were described in terms of numerical abundance and frequency of occurrence of prey taxa. A total of 1642 fish individuals, belonging to 17 species, were examined. In total, 45,674 prey individuals were identified belonging to 110 prey taxa, most of which were Malacostraca including their larvae and Copepoda (41,175 individuals identified to 71 taxa). Four different trophic groups were identified: herbivorous, pelagic, benthic (hyperbenthic) and piscivorous. Trophic diversity patterns o...
In this study we present a list of invasive/potential invasive alien species in the East and Sout... more In this study we present a list of invasive/potential invasive alien species in the East and South European Network for Invasive Alien Species (ESENIAS) countries with marine borders. The species were classified according to the existing literature and experts’ judgment, as established, casual, invasive and expected. Finally, factsheets were compiled for ten species of high importance based on their expanding/invading character. Of the 160 species comprising the list, 149 were already present in the ESENIAS countries, while eleven were invasive species either present in the Mediterranean or in other European Seas, likely to be recorded in the ESENIAS countries. The majority of the species were of Red Sea/IndoPacific origin (97 species; 60.6%). Italy, Turkey and Greece were the countries with the highest representation of species (159, 152 and 139 species respectively), due to their extended coastline and the number of scholars working on marine invasive species. The highest number o...
This study presents the diet composition of 43 of some of the most abundant fish species from the... more This study presents the diet composition of 43 of some of the most abundant fish species from the North Aegean Sea, Greece. According to the diet analysis and fractional trophic level previously reported in the literature, 20 of the studied species were omnivores with a preference for animals and the other half were carnivores (15 with preference for fish and Cephalopoda, and seven with preference for fish and Decapoda), whereas Parablennius gattorugine was the only recorded omnivore with a preference for plant material. Finally, according to the results of Schoener’s index, diet overlap between species was recorded in a small number of cases (33 out of the 903 pairs examined). Yet, competition among diet-overlapping species may be minimised by either morphological differentiations and/or habitat segregation.
An up-to-date systematic review and unofficial codification of the national fisheries legislation... more An up-to-date systematic review and unofficial codification of the national fisheries legislation was performed, along with an up-to-date systematic review of environmental, archaeological and maritime legislation, about spatio-temporal restrictions of fishing activities by all fishing gears in the Aegean Sea. Spatio-temporal restrictions established by the European Union and the General Fisheries Commission for the Mediterranean were also reviewed. A database was built, including detailed information on the Fisheries Restricted Areas (FRAs) being identified. All FRAs were mapped, as polygons in Geographic Information System shapefiles. The national fisheries, environmental, archeological and maritime legal framework comprises of 32, 2, 37 and 43 legal acts respectively; EU and GFCM legislation consists of one Regulation and one Recommendation respectively. A total of 511 national (254 of fisheries, 21 of environmental, 85 of archaeological and 151 of the maritime legislation), 6 EU...
The multi-level benefits that marine organisms gain when protected from fishing are well acknowle... more The multi-level benefits that marine organisms gain when protected from fishing are well acknowledged. Here, we investigated the effects of a 40-year trawling ban on the status of targeted and non-targeted marine species within a major fishing ground in the northeastern Mediterranean Sea (Thermaikos Gulf, Aegean Sea). Biomass and somatic length of fish and invertebrates (six commercial and three non-commercial demersal species) were measured in three areas of varying fishing pressure, depending on the temporal and spatial operational regimes of fishing vessels. The positive effects of fishing restrictions on the studied demersal stocks were clearly revealed, as the commercial fish species exhibited higher biomass in the intermediate and low pressure areas, as well as increasing maximum and mean total length (and other length indicators) with decreasing fishing effort. The mean total length of non-commercial species generally did not differ among areas, except for species caught and ...
In this study we updated the previous compilation of the feeding habits and trophic levels (TROPH... more In this study we updated the previous compilation of the feeding habits and trophic levels (TROPHs) of Mediterranean fish. In total, 172 publications were retrieved and analysed. Collected data refer to 146 species, with a TROPH value ranging from 2.00 to 4.54. The analysis of TROPH distribution verified the previously proposed classification of species into functional trophic groups. Overall, information on diet composition exits for 203 fish species out of the >700 fishes from the Mediterranean, a fact clearly showing that feeding habits are understudied despite their importance in ecological applications and fisheries management. More than half (60.6%) of these species are classified as omnivores with preference to animal material, 36.5% are carnivores, 1.9% are omnivores with preference to plants, and two (i.e. Siganus luridus and S. rivulatus) are pure herbivores. Finally, towards the direction of filling in information gaps, recommendations for future research are given.
In this Collective Article on “New Mediterranean Biodiversity Records”, we present additional rec... more In this Collective Article on “New Mediterranean Biodiversity Records”, we present additional records of species found in the Mediterranean Sea. These records refer to eight different countries throughout the northern part of the basin, and include 28 species, belonging to five phyla. The findings per country include the following species: Spain: Callinectes sapidus and Chelidonura fulvipunctata; Monaco: Aplysia dactylomela; Italy: Charybdis (Charybdis) feriata, Carcharodon carcharias, Seriola fasciata, and Siganus rivulatus; Malta: Pomacanthus asfur; Croatia: Lagocephalus sceleratus and Pomadasys incisus; Montenegro: Lagocephalus sceleratus; Greece: Amathia (Zoobotryon) verticillata, Atys cf. macandrewii, Cerithium scabridum, Chama pacifica, Dendostrea cf. folium, Ergalatax junionae, Septifer cumingii, Syphonota geographica, Syrnola fasciata, Oxyurichthys petersi, Scarus ghobban, Scorpaena maderensis, Solea aegyptiaca and Upeneus pori; Turkey: Lobotes surinamensis, Ruvettus pretios...
As part of its policy, Mediterranean Marine Science started from 2014 to publish a new series of ... more As part of its policy, Mediterranean Marine Science started from 2014 to publish a new series of collective article with fisheries-related data from the Mediterranean Sea. In this first collective article we present length frequencies and weight-length relationships for the northern brown shrimp Farfantepenaeus aztecus in the eastern Mediterranean, length-weight relationships for 10 fish species in the North Aegean Sea, the feeding habits for 11 sparid fishes in the North Aegean Sea, a review of the existing literature on the feeding and reproduction of common carp Cyprinus carpio in Anatolia (Turkey) and mouth dimensions and the relationships between mouth area and length for seven freshwater fishes from Lake Volvi (Northern Greece).
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