A comparative study of success and failure of fishery cooperatives in the Aegean, Turkey

This study assessed the performance of fishery cooperatives in six selected fishing areas along the central and southern Aegean coasts of Turkey during the 2002–2003 fishing season, in particular with regard to their stated objectives (e.g. member-fisher satisfaction recognition by fishery management authorities). A total of 127 member-fishers (72% of all active fishers in the study area) as well as fishery cooperative directors were interviewed. The results indicated the various strengths of these cooperatives as well as their limitations. Performance below full potential was due to internal factors such as lack of solidarity and qualified business management skills, as well as external factors relating to weak legislative support by the government, the tax system and the lack of training. However, through their contribution to local society and their function in assisting management bodies, cooperatives play a significant role in Turkish small-scale fisheries. They are therefore in need of further capacity building through specific encouragement from the government, academics, and fishers in order to improve their performance.     

Fishing near sea-cage farms along the coast of the Turkish Aegean Sea

This study reports on the yield of commercially important species captured intentionally around and under fish-cage farms using specific types of gear from both sea-cage farmers and artisanal fishermen, and to identify the species composition of these catches. The 2004–2008 research was carried out in 21 fish farms, randomly chosen along the coast of Izmir Province on the Aegean Sea. A total of 91 persons were interviewed, including directors, fishers from the fish farms and artisanal fishermen. The technical characteristics of a special trap used by some fish farmers were diagramed. Total wild fish catch quantities as well the species raised in the sea-cages were recorded. A total of 34 finfish and four invertebrate species were identified from the sea-cage farm fishery. Eight fish species according to the descending quantities raised were bogue ( Boops boops ), grey mullet ( Mugil spp.), blackspot seabream ( Pagellus bogaraveo ), salema ( Sarpa salpa ), common two-banded seabream ( Diplodus vulgaris ), annular seabream ( Diplodus annularis ), striped seabream ( Lithognathus mormyrus ) and gilthead seabream ( Sparus aurata ). Mean quantities of wild fish caught from 2004 to 2008 in a sampled farm were 13 998 ± 210, 34 434 ± 482, 30 116 ± 529, 27 893 ± 429, and 32 366 ± 808 kg, respectively. There were significant differences between fish amounts and years (P   < 0.05).     

Fish by-catch species from coastal small-scale shrimp trammel net fishery in the Aegean Sea (Izmir Bay, Turkey)

Fish by‐catch from coastal small‐scale shrimp trammel net fishery was estimated from fishery‐dependent surveys in Izmir Bay (Aegean Sea), Turkey, during the 2004 and 2005 fishing seasons. Sampling data were obtained from 170 observations onboard 18 commercial fishing vessels. Fifty‐two species belonging to 31 families of fish, including cephalopods, constituted the by‐catch. Diplodus annularis was the most abundant by‐catch species followed by Loligo vulgaris > Sepia officinalis > Mullus barbatus > Boops boops > and Solea vulgaris. The estimated total ratio of fish by‐catch to shrimp was 1 : 1.09 kg.     

Fisherwomen in the Turkish fishery,southern Aegean Sea

There are no official records on the active involvement of women in Turkish fisheries nor do governmental institutions acknowledge their participation. The main purpose of this study was to validate their involvement and convey their socio‐demographic status and position in the profession. The study material consisted of data collected from on‐site surveys and interviews with fisherwomen living in the southern Aegean region of Turkey. Interviewed were fisherwomen working either alone or with their husbands. The ‘snowball’ sampling method was adopted for data collection from a total of 96 interviews with fisherwomen between August and December 2007. In the entire southern Aegean region only ten women were members of a cooperative. Although fisherwomen truly fulfill all functions that the profession requires (both pre‐ and post‐harvest phases), results of the study demonstrate that they are ignored in pertinent policies. The study suggests that gender‐oriented data should also be collected; the contribution of fisherwomen to the fisheries sector should be considered and included in related policies.     

Diet composition of the juvenile chub mackerel (Scomber japonicus) in the Aegean Sea (Izmir Bay, Turkey)

Stomach contents of 296 juvenile chub mackerel (Scomber japonicus Houttuyn, 1782) specimens were examined based on samplings carried out in Izmir Bay (Aegean Sea, Turkey) during 2001. In terms of percentage weight (W%), fishes were the main food during summer and autumn. Thaliaceans (Salpa sp.) constituted the most important food source in winter, whereas planktonic crustaceans (Amphipoda, Copepoda) were the main prey during spring. According to the Bray–Curtis similarity index, diet of the chub mackerel was 64.1% similar during the summer, winter and autumn seasons.     

The productive and optical status of the oligotrophic waters of the Southern Aegean Sea (Cretan Sea), Eastern Mediterranean

Primary production, pigment concentrations and spectral measurementsof downwelling irradiance were made at four stations in fourseasons (spring, summer, autumn, winter) during 1994 in thewaters of the South Aegean Sea (Cretan Sea), Eastern Mediterranean.Rates of production were determined using in Situ incubationtechniques and included measurements at the surface microlayer.Depth-integrated values averaged over season were 5.66 mg Cm^–2 h^–1 for primary production and the correspondingchlorophyll (Ch1) a and phaeophytin (Phaeo) a values had meansof 4.87 and 1.21 mg m^–3 respectively. The assimilationratio remained very low (mean over season: 1.19 mg C mg^–2Chl a h^–1 as did the Phaeo a/Chl a ratio (mean over season:0.24). The annual production for the area was estimated to yield24.79 g C m^–2 year^–1. Primary production and Chla estimates showed statistically significant seasonal, spatialand depth variations. The spectral values of the attenuationcoefficient Kd (     

The very rare and little‐known fishes along the coasts of Izmir (Aegean Sea,Turkey) in the past 40 years (1969–2008)

The objective of this study was to document the frequency of occurrence of very rare fish species as well as to note the changes in diversity over time. Fish species recorded fewer than five times over the past 40 years (1969–2008) from the coasts of Izmir (central Aegean Sea) were included in the account and considered as being very rare. The records are listed chronologically. Fish species recently recorded in the area for the first time are also included. Changes in qualitative and quantitative composition of the ichthyofauna along the coasts of Izmir are also discussed.     

Macrozoobenthic Assemblages of the Evros Delta (North Aegean Sea)

The composition of the macrozoobenthic assemblages of the Evros Delta (North Aegean Sea) has been investigated by means of 4 replicate quantitative samples, collected at 35 sites. The information obtained from the numerical analysis of the faunal samples and the analysis of other data (values of the main physico-chemical parameters) revealed the presence of a single community. The faunal composition of this community varies locally according mainly to the salinity and secondly to the particle size of the substrate. The community is described on the basis of its biological parameters and compared with corresponding assemblages from other areas.     

Spirorbinae (Polychaeta:Serpulidae) from Chios (Aegean Sea)

Twelve species are described, of which two are new, viz. Spirorbis (Janua) gnomonicus and Spirorbis (J.) parvulus, and three others have been recognized only very recently, viz. S. (Pileolaria) clavus, S. (P.) endoumensis, S. (P.) heteropoma. Some such as 5. (jf.) corrugatus and S. (P.) koehleri were widely distributed between depths of 0–60 m, but others showed a tendency towards depth zonation, with S.(J.)pagenstecheri abundant in shallow and S. (Spirorbis) cuneatus in somewhat less shallow water. 5. (P.) pseudomilitaris and S. (Marsipospira) striatus were confined to greater depths except where the former occurred amongst ships fouling and the latter in a dark cave. 5. (P.) militaris seems rather uncommon.
A remarkably high percentage of the species (over 80%) are opercular incubators. Outside the Mediterranean, the only areas known to have similar percentages are Ceylon and the West Indies, suggesting that the habit may have originated in the Sea of Tethys.     

Feeding Ecology of Black-bellied Anglerfish Lophius budegassa in the Central Aegean Sea,Turkey

Journal of Ichthyology - Anglerfishes Lophius spp. are gaining high economic value day by day and becoming demand species worldwide. The black-bellied anglerfish, Lophius budegassa (Spinola, 1807)...     

Reproductive biology of Raja clavata (Elasmobranchii: Rajidae) from Southern Black Sea coast around Turkey

Specimens of Raja clavata were monthly collected at the coast of Havaalan? (Trabzon/Turkey) from January 2009 to December 2009 at depths between 20 and 40?m. A total of 230 individuals of thornback ray (131 females and 99 males) were collected by bottom trawls during research cruises. Using logistic regression, it was determined that TL at 50% maturity of males was 718?mm TL and of females 746?mm TL. The ovarian fecundity ranged from 27 to 60 yellow follicles in both ovaries. Females carrying egg cases were found in July and October. Variations in the gonadosomatic and hepatosomatic indices indicated a continuous reproductive cycle during the year.     

The distribution of dinoflagellate cysts along the Galician (NW Spain) coast

We have studied the distribution of dinoflagellate cysts along10 Galician rías and part of their adjacent continentalshelf. Cyst abundance in the area averaged 856 cysts ml^–1,which is of the same order of magnitude as those found in otherareas of the western European coast. It was higher in the ríasthan in the shelf, having a very heterogeneous distribution,especially in the former. Cyst assemblages in these two areaswere different, suggesting that differences are due to cystproduction rather than to accumulation. Principal componentanalysis, cluster analysis, distribution of macroscopic characteristicsof cyst populations and distribution of single species suggestthat local factors control the distribution in the rías.Nevertheless, a general pattern that splits the whole area intotwo-to the north and to the south of the ría de Camariñas-canbe distinguished. This latter trend was also observed in theshelf and, in our opinion, It should be attributed to threeconcurrent causes: the effect of different upwelling intensitiesor frequencies, the effect of the different numbers and sizesof the ría in each area, and the effect of the presenceof different water masses in these areas. The cyst distributionof a number of individual species was examined and showed threegeneral groups: species with very restricted distribution, suchas Alexandrium sp2 or Scrippsiella sp4, species with a widespreaddistribution along the rías, such as several Scrippsiellaspecies, and species mainly distributed along the shelf, suchas Gymnodinium catenatum. The distribution of cysts belongingto red tide organisms fits quite well with that of their correspondingmotile phases dunng the three previous years for most of theorganisms studied and also during the 1992–1993 period(7–8 years later), but the role of this resting stagein initiating such blooms seems to be highly variable with species.     

Length–weight relationships of 24 fish species from the North Aegean Sea, Turkey

Length–weight relationship parameters of the form W = aL^b are presented for 24 fish species from the North Aegean Sea: Scyliorhinus canicula, Mustelus mustelus, Squalus acanthias, Torpedo marmorata, Dipturus oxyrinchus, Raja clavata, R. miraletus, Dasyatis pastinaca, Gymnura altavela, Myliobatis aquila, Chimaera monstrosa, Conger conger, Argentina sphyraena, Chlorophthalmus agassizi, Caelorinchus caelorhincus, Gadiculus argenteus argenteus, Phycis blennoides, Hoplostethus mediterraneus, Capros aper, Macroramphosus scolopax, Helicolenus dactylopterus, Peristedion cataphractum, Lesueurigobius friesii and Lepidopus caudatus.     

Zoobenthos-inhabiting Sarcotragus muscarum (Porifera: Demospongiae) from the Aegean Sea

The cavities and outer surfaces of 20 individuals of the sponge Sarcotragus muscarum collected from the Turkish Aegean coast during July–September 1993 contained a total of 148 zoobenthic species with 5299 individuals belonging to seven taxonomic groups. Among these, Polychaeta accounted for 60% of the total number of species, while Crustacea comprised 71% of the total number of individuals and 40% of the wet weight of biomass. The amphipod and decapod crustaceans Tritaeta gibbosa and Synalpheus gambarelloides, and the bivalve Hiatella arctica, were the most abundant species on the sponge samples both in terms of number of individuals and biomass values. The community structure inside the sponges was greatly influenced by the nature of the substratum around the sponge, and by the overwhelming population of the Lessepsian echinoderm Ophiactis savignyi. Number of species, biomass and diversity index values were found to be positively related to the sponge volume. Mean density and biomass of the associated taxa are 0.22 ind cm^–3 and 11.63 mg cm^–3, respectively.     

The composite trophic status index (TRIX) as a potential tool for the regulation of Turkish marine aquaculture as applied to the eastern Aegean coast (Izmir Bay)

This research examines the current water quality status of Izmir Bay, using the trophic index (TRIX) as a tool for the regulation of Turkish marine finfish aquaculture. In 2007, new legislation was enacted in Turkey related to the protection of coastal waters, especially those of enclosed bays and gulfs, from pollution by fish farming. However, the legislation does not apply to any other coastal zone stakeholders; for this reason the entire Izmir Bay was examined. Use of the composite trophic status index (TRIX) produced mean TRIX values of 3.6 for the aquaculture area (AA) and 2.5 for areas of the outer bay where no aquaculture takes place; this indicates ‘no risk of eutrophication’ as defined by Turkish law. In the inner Izmir Bay, there is a mean TRIX value of 4.3, which is above the threshold of four and typical for ‘high eutrophication risk’ areas, as expected because of heavy urbanization. The study then applied the UNTRIX indices adjusted to local conditions, revealing that both the inner bay and the aquaculture area (AA) can be classified as of ‘poor’ status whereas the outer bay can be defined as ‘good’. The UNTRIX‐based trophic classification is in good agreement with TRIX for both the outer and inner parts of the bay; however, there is no agreement regarding the classification of the aquaculture area.     

Some population parameters of Ruditapes philippinarum (Bivalvia,Veneridae) on the southern coast of the Marmara Sea,Turkey

Ruditapes philippinarum, a venerid clam, is a dominant species in the sandy and muddy areas in the coastal waters of the Marmara Sea. Intensive commercial harvesting of this species is conducted in these regions. We studied the population dynamics of R. philippinarum on the southern coast of the Marmara Sea (Band?rma). Samples were collected on a monthly basis between September 2012 and August 2013. Seasonal von Bertalanffy growth parameters using the length–frequency distribution of R. philippinarum were estimated at L _∞ = 67.50 mm and K = 0.33 year^?1, and the seasonal oscillation in growth rate was 0.53. The slowest growth period was in January. The growth performance index and potential lifespan were 3.182 and 8.06 years, respectively. The growth relationship was confirmed to have a positive allometric pattern. The average total mortality rate was estimated to be 0.777 year^?1, whereas the natural and fishing mortality rates were 0.539 and 0.238 year^?1, respectively. The current exploitation rate of R. philippinarum was 0.306. The recruitment pattern peaked during June–August, and spawning occurred between May and August. The results of this study provide valuable information on the status of R. philippinarum stocks.     

Orientation anomalies (reversal) of the four-spotted megrim (Lepidorhombus boscii) in the Aegean Sea

Reversal occurred in four out of 15 325 specimens (0·026%) of four-spotted megrim Lepido-rhombus bascii caught in the Aegean Sea.