Current marine pressures and mechanisms driving changes in marine habitats

Human activities and the resultant pressures they place on the marine environment have been widely demonstrated to contribute to habitat degradation, therefore, their identification and quantification is an essential step towards any meaningful restoration effort. The overall scope of MERCES Deliverable 1.2 is to review current knowledge regarding the major marine pressures placed upon marine ecosystems in EU waters and the mechanisms by which they impact habitats in order to determine potential restoration pathways. An understanding of their geographical distribution is critical for any local assessment of degradation, as well as for planning conservation and restoration actions. This information would ideally be in the form of maps, which: (a) compile single or multiple activities and pressures over broad scales, integrating and visualizing available data and allowing direct identification of aggregations as well as gaps and (b) may be overlaid with habitat maps (or any other map layer containing additional information), thus combining different data levels and producing new information to be used for example when implementing EU policies. The deliverable also documents typical example habitat case studies, the prominent impacts and consequences of activities and pressures towards the identification of possible restoration or mitigation actions. Finally the deliverable discusses pressures, assessments, marine spatial planning and blue growth potential. Activities and pressures are used in a strict sense, where marine activities are undertaken to satisfy the needs of societal drivers (e.g. aquaculture or tourism) and pressures are considered to be the mechanism through which an activity has an actual or potential effect on any part of the ecosystem (e.g. for demersal trawling activity, one pressure would be abrasion of the seabed). Habitats are addressed using a nested approach from large-scale geological features (e.g. shallow soft bottoms) to species-characterised habitats (e.g. Posidonia meadows) because of the way they are referred to in current policy documents which lack standard and precise definitions

Feeding ecology and trophic level of Chimaera monstrosa Linnaeus, 1758 (Holocephali: Chimaeridae) in the Eastern Mediterranean

WOS: 000372096000009The feeding ecology of Chimaera monstrosa at a depth of 550 m was studied off Sigacik Bay, Eastern Mediterranean, in 2008. Forty males and 57 females with a length between 7.80 and 45.5 cm were caught. 33 stomachs contained food items. The diet was composed of 11 prey items belonging to 6 groups: Bryozoa, Cnidaria, Crustacea, Mollusca, Tunicata, and Teleostei, of which Crustacea (IRI% [Index of Relative Importance]=80) and Mollusca (IR%=16) were the most abundant prey groups. The trophic level was estimated at 3.50, which is similar to the results from other studies in the western and northern part of the Mediterranean and the Atlantic Ocean but is higher than in the North Sea.TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [2209]This work was supported by TUBITAK under the grant program 2209

Diet composition of the Thornback Ray, Raja clavata Linnaeus, 1758 (Elasmobranchii: Rajidae) in the Turkish Aegean Sea

WOS: 000346850900006The diet of Raja clavata (Thornback Ray) was studied in 2008-2009 in Sigacik Bay in the eastern Mediterranean, based on 187 stomach contents obtained by commercial trawl operations. 40 different prey species were found. Mysidacea, Parapenaeus longirostris and Plesionika sp. were the most abundant prey items. The results indicate that the main prey varies considerably depending on the ecological characteristics of the habitat

Length-weight relationship of cartilaginous fish species from Central Aegean Sea (Izmir Bay and Sığacık Bay)

In this study, length–weight relationship parameters of 16 out of 30 caught cartilaginous fish species examined (11 Sharks, 18 Batoids and 1 Chimaera) from the Central Aegean Sea and presented. Samples were caught from depths of 500 m by research vessel and a commercial trawler, between 2008-2009. The values of the slope b in the length-weight relationship parameters ranged from 2.79 (Torpedo marmorata) to 3.78 (Scyliorhinus stellaris), a values from 0.0002 (Scyliorhinus stellaris) to 0.9713 (Dasyatis pastinaca). This study has optained and examined the most chondrichthyan species among the studies in the eastern MediterraneanBu çalışmada Orta Ege Denizi'nden yakalanmış 30 kıkırdaklı balık türünün (11 köpekbalığı, 18 vatoz ve 1 Chimaera) 16'sının boy-ağırlık ilişkisi incelenmiş ve sunulmuştur. Örnekler bir araştırma gemisi ve bir ticari trol teknesi ile 500 m derinlikten 2008-2009 yılları arasında yakalanmıştır. Boy-ağırlık ilişkisi parametrelerinden b değeri 2.79 (Torpedo marmorata) ile 3.78 (Scyliorhinus stellaris), a değerleri 0.0002 (Scyliorhinus stellaris) ile 0.9713 (Dasyatis pastinaca).arasında değişmiştir. Bu çalışma doğu Akdeniz'de yapılmış çalışmalar arasında en yüksek tür sayısını elde etmiş ve incelemişti

Reproductive biology of pink cuttlefish Sepia orbignyana in the Aegean Sea (eastern Mediterranean)

WOS: 000323423000006Some aspects of the reproductive biology of Sepia orbignyana, such as fecundity, spawning strategies, and gonad histology, have been studied in 1048 specimens (538 males and 510 females) caught during trawl surveys from May 2008 to April 2009 in the Aegean Sea. The length at 50% maturity was estimated as 50 mm for males and 70 mm for females. The smallest mature female had a mantle length (ML) of 36 mm; the smallest mature male had a 32-mm ML. The total egg counts (potential fecundity) in females of 60-84 mm in ML varied between 201 and 1532. The spermatophore counts in mature males (ML = 42-67 mm) were between 68-1055, with a mean of 485.EBILTEM (Science and Technology Center of Ege University)Ege University [2008/SUF/004]; Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [108Y102]This study was financially supported by EBILTEM (Science and Technology Center of Ege University) (Project No: 2008/SUF/004) and the Scientific and Technological Research Council of Turkey (TUBITAK, Project No: 108Y102). We are indebted to Prof Dr Stephen Astley from the Ege University Science Faculty for editing the text. We would also like to thank both referees for their valuable and constructive comments

İzmir Körfezi’nde Kancaağız Pisi balığının Citharus linguatula (L., 1758) bazı biyolojik özellikleri

In this study, some biological features of spotted flounder Citharus linguatula (L.,1758) were investigated from İzmir Bay. 2555 specimens were captured with bottom trawl net by R/V Egesuf between January 2005-May 2006. It is determined that the samples of population distributed between I-VI age groups. Minimal, maximal and mean total length were established as 9.1cm, 23.9 cm and 15.90±0.096 cm, respectively. Minimal, maximal and mean weights were found as 5.02g, 105.34g and 32.06±0.61g, respectively. The weight-length relationships and von Bertalanffy growth equations were calculated as W=0.005*L3.14, r= 0.98, Lt = 27.38 * [1-e-0.2142 (t+1.6353)]Bu çalışmada, İzmir Körfezi'nde kancaağız pisi balığının Citharus linguatula ,(L., 1758) bazı biyolojik özellikleri tespit edilmiştir. Ocak 2005-Mayıs 2006 tarihleri arasında, İzmir Körfezi'nden Egesüf Araştırma Gemisi'nden trol ağı ile aylık olarak toplam 2555 adet elde edilmiştir. Bireylerin I-VI yaş grupları arasında dağılım gösterdiği saptanmıştır. Minimum, maksimum ve ortalama total boy sırasıyla, 9,1cm, 23,9cm ve 15,90±0,096 cm'dir. Minimum, maksimum ve ortalama ağırlık sırasıyla, 5,02g, 105,34g ve 32,06±0,61 g'dır. Total boy-ağırlık ilişkisi esas alınarak hesaplanan boy ağırlık ilişkileri, W=0,005*L314, r= 0,98 olarak tespit edilmiştir. von Bertalanffy büyüme parametreleri tüm bireyler için Lt = 27,38 * [1-e-0,2142 (t+1,6353)] olarak hesaplanmıştı