Alper Doğan

Seasonal dynamics of soft bottom zoobenthic communities in polluted and unpolluted areas of Izmir Bay (Aegean Sea)

The polluted and unpolluted parts of Izmir Bay (Aegean Sea) were sampled seasonally in 1995 and 1996 in order to delineate effects of pollution on the spatial-temporal distributions of soft bottom benthic animals. A total of 298 species, represented by 6014 individuals, belonging to 10 major groups were determined, of which Polychaetes accounted for almost 51% of the total number of species (153 species) and 82% of the total number of individuals (4942 specimens). Crustaceans and molluscs were next dominant after the Polychaeta. By utilising the result of the cluster analysis, four main species assemblages were recognised in the area, each containing different dominant species. The heavily polluted inner bay, which was mainly dominated by the opportunistic polychaetes,Capitella capitata, Polydora spp. andOphiodromus pallidus, reached azoic conditions in summer and autumn. As the results of the present study compare with those of previous studies held in the bay, it can be concluded that pollution in the bay tends to increase and adversely affects distributions of zoobenthic animals particularly in the inner part of Izmir Bay.

Spatio-temporal distributions of zoobenthos in Mersin Bay (Levantine Sea, eastern Mediterranean) and the importance of alien species in benthic communities

Abstract Spatio-temporal variations of soft-bottom zoobenthic communites in Mersin Bay were examined at seven stations between February and October 2009. A total of 337 species were encountered, of which Polychaeta had the highest number of species (136 species), and Mollusca possessed the highest number of individuals (65% of total specimens) and biomass (59% of total biomass). The highest benthos density (max. 9760 ind. m−2) and biomass (max. 133 g m−2) were found at shallow-water stations, whereas the highest diversity index values were calculated at the deepest station. The molluscs Cerithidium diplax, Corbula gibba and Bittium reticulatum dominated the area. Changes of zoobenthic communities were spatial rather than temporal and were strongly correlated with depth and the sediment structures. A total of 40 alien species were found in the area, of which 15 species were possibly transported to the area by ships and the others were Lessepsian migrants. The most domiant alien species in the area were C. diplax, Finella pupoides, Notomastus mossambicus and Amphiodia obtecta. Alien species formed dense populations at shallow water stations, and accounted for 12% of total number of species and 31% of total number of individuals in the area. The community parameters estimated for alien species significantly differed among stations but not among sampling periods. The main factors negatively affecting the number of alien species and individuals were depth, the clay percentage and total organic carbon concentration in sediment. The number of native species and individuals in the area show moderate positive correlations with those of aliens.

First record of the Indo-Pacific species Electroma vexillum (Mollusca: Bivalvia: Pterioida) in the eastern Mediterranean

Iskenderun Bay (north-west Levantine Sea) is intensely industrialized but it is oil pollution that affects most of the coastal and marine ecosystems in the area. Molluscan species diversity in the bay is changing rapidly over the last decades due to the introduction of non-indigenous species of Indo-Pacific origin. To date, 67 of the 181 recorded molluscan species are aliens (37%), a percentage by far higher than anywhere reported. A population of the bivalve Electroma vexillum , whose original distribution is the Indian Ocean and the Red Sea, was encountered and recorded for the first time in 2002 in the discharge canals of the Iskenderun Iron and Steel Factory. The distribution of E. vexillum was very restricted in the canal, presumably limited by the temperature (23–36°C). Its occurrence is attributed to shipping.

Response to oxygen deficiency (depletion): Bivalve assemblages as an indicator of ecosystem instability in the northern Adriatic Sea

Benthic communities represent a powerful tool for the detection of natural and anthropogenic disturbances, as well as for the assessment of marine ecosystem stability. This paper shows that bivalve assemblages could serve as excellent indicators of disturbance and ecosystem instability. The goal of this study was to compare two sets of data in order to determine the differences between two different periods belonging to bivalve assemblage in the muddy detritic bottom of the northern Adriatic Sea in the post-anoxic period during December 1989, 1990, 1991 and quite a while later, during 2003, 2004 and 2005. Abundances of some indicator species such as Corbula gibba, Modiolarca subpicta and Timoclea ovata were detected during the post-anoxic period. Recruitment in the quality of bivalve assemblages was proved by the ecologic and biotic indexes during 2003, 2004 and 2005, during a period of relatively stable ecological conditions. Fluctuation in bivalve diversity due to the ecological quality of the marine ecosystem in the eastern part of the northern Adriatic Sea is also discussed.

Decapod crustaceans new to the fauna of Cyprus

Cyprus is surrounded by the waters of the Levantine Sea, eastern Mediterranean, characterized by a higher temperature and salinity as compared to the rest of the Mediterranean Sea (Galil, 1992; Kocatas et al., 2001). The first study on the decapod crustacean fauna of the island was carried out by Heller (1863), and only 12 species had been reported by the late 19th century (see Unger & Kotschy, 1865; Plateau, 1884; Adensamer, 1898). Until recently, 150 species of decapods (44 Natantia, 11 Macrura Reptantia, 24 Anomura, 71 Brachyura) were known to occur along the Cyprus coasts (Lewinsohn & Holthuis, 1986; Kocatas et al., 2001). The study on which our present report is based, was conducted along the northern coast of Cyprus in the period 18.x.2003-03.xi.2003. Specimens were obtained by means of a Van Veen grab, a dredge, and a trawl employed over sandy-silt bottoms at depths between 11 and 225 m (fig. 1). The specimens, including those photographed, are preserved in 4% formaldehyde and deposited in the Museum of the Faculty of Fisheries, Ege University, Bornova-Izmir. With this report, the number species of Decapoda known to occur on the Cyprus coasts has increased to 152: Sicyonia carinata (Brunnich, 1768) and Upogebia mediterranea Noel, 1992 are new records for the decapod fauna of Cyprus. The nomenclature for these species follows Marine Species (2007).

Macrobenthic fauna associated with the invasive alien species Brachidontes pharaonis (Mollusca: Bivalvia) in the Levantine Sea (Turkey)

The invasive alien mytilid species, Brachidontes pharaonis , forms a biogenic habitat in the mediolittoral and upper-infralittoral zones of the Levantine Sea, hosting a number of alien and native species. Examinations of samples taken from dense, continuous mussel beds at seven stations along the coast of northern Levantine Sea yielded 187 macro-benthic invertebrate species belonging to 11 taxonomic groups. Polychaeta accounted for 46% and 37% of the total number of species and individuals, respectively. The top three dominant species in the mussel beds were Stenothoe gallensis, Spirobranchus kraussi and Mytilaster minimus . The species with the highest frequency values on the mussel beds were Pseudonereis anomala, Phascolosoma stephensoni and Elasmopus pocillimanus . The highest density and biomass of the associated fauna were estimated as 42,550 ind m −2 and 1503 wwt g m −2 , respectively. The species number in samples varied between 14 and 47 species. The environmental variables best explaining variations in zoobenthic community structures were salinity, dissolved oxygen and total inorganic nitrogen in the water column. The biotic indices, TUBI and ALEX, classified the ecological status of one or two stations as moderate or poor, based on the relative abundances of ecological and zoogeographic groups, respectively. A total of 21 alien species were found to be associated with the mussel bed, of which Syllis ergeni is being newly considered as a new established alien species for the Mediterranean Sea. The maximum density of associated alien species was calculated as 30,300 ind m −2 . The alien species assemblages were greatly affected by salinity and total inorganic nitrogen.

The first record of Chelonibia testudinaria (Linnaeus, 1758) (Cirripedia, Chelonibiidae) on the Turkish Aegean coast

The barnacle genus Chelonibia is known to be represented by four living species today (Hayashi, 2013). These all have a wide distribution in the world’s oceans and three of them have been reported from the Mediterranean Sea up to date (Hayashi, 2013). Among these, Chelonibia testudinaria (Linnaeus, 1758), which was already reported from many tropical and subtropical parts of oceans and seas (Hayashi, 2013) is known from the entire Mediterranean. It has often been found as an epibiont on marine turtles (Newman & Ross, 1976) and rarely also on inanimate objects (Relini, 1980; Kitsos et al., 2003). One of the other two species, Chelonibia patula (Ranzani, 1818), which is a cosmopolitan species (Darwin, 1854; Newman & Ross, 1976; Relini, 1980; Frazier & Margaritoulis, 1990; Kitsos et al., 2003), is usually reported from crustaceans and gastropods (Darwin, 1854). It was also reported from the surface of inanimate objects by Relini (1980) and Frazier & Margaritoulis (1990), and as an ongrowth on marine turtles by Ross & Jackson (1972). The last species, Chelonibia caretta (Spengler, 1790) is generally found on Caretta caretta (Linnaeus, 1758) and shows a distribution comprising the Atlantic, Pacific, and Indian oceans, as well as the Mediterranean Sea (Monroe & Limpus, 1979; Caine, 1986; Hayashi, 2013). On the other hand, Cheang et al. (2013) mentioned that based on both morphological and molecular evidence, C. testudinaria and C. patula from SE Asia and Taiwan are the same species and belong to the western Pacific population of C. testudinaria as identified by Rawson et al. (2003). Moreover, according to Zardus et al. (2014) C. testudinaria, C. patula, and also C. manati Gruvel, 1903, are genetically indistinguishable species.

On the presence of Pandora inaequivalvis (Bivalvia: Pandoridae) on the Levantine coast of Turkey

In a benthic study conducted in Iskenderun Bay, Turkey, in July 2007, the pandorid bivalve Pandora inaequivalvis was encountered at four stations having depths of 1.5–7.5 metres and muddy sand bottoms. This is the first record of this species for the Turkish part of the Levantine Sea.

Temporal variation of the soft-bottom molluscan fauna in north-western İskenderun Bay (Levantine Sea)

Abstract The present study was performed to follow temporal variation of the soft-bottom molluscan fauna in north-western Iskenderun Bay. The benthic material was collected at a depth ranging from 3 to 37 m at 12 sampling locations by the van Veen grab sampler in the summer season of 2012, 2013 and 2014. A total of 133 species were identified in the study area through the examination of the collected material. Among the identified species, Corbula gibba (Olivi, 1792), Bittium reticulatum (da Costa, 1778), Nassarius pygmaeus (Lamarck, 1822), Cerithidium diplax (Watson, 1886) and Finella pupoides Adams, A., 1860 have the highest values of the frequency index. According to the Bray-Curtis similarity index, these species also have an important effect on the similarity between the stations. Furthermore, C. diplax and F. pupoides are alien species to the Mediterranean.