Biology of the thornback ray (Raja clavata Linnaeus, 1758) in the North Aegean Sea

Cabbar, Koray; Yiğin, Cahide Çiğdem

doi:10.2478/oandhs-2021-0011

Abstract

The study deals with aspects of the population dynamics in the thornback ray (Raja clavata L., 1758), one of the most abundant cartilaginous fish caught in the North Aegean Sea. Females accounted for 73.08% and males 26.92% of all individuals. Total length of females and males ranged between 50.2 and 89.9 cm (disc width: 33.4–62.0 cm), and between 43.1 cm and 82.7 cm (disc width: 30.7–64.2 cm), respectively. Relationships between total length (TL) and total weight (TW), and between disc width (DW) and total weight (TW) were described by the equations: TW = 0.0041 TL^3.10 and TW = 0.0178 DW^3.03, respectively. Age data derived from vertebrae readings were used to estimate growth parameters using the von Bertalanffy function: L_∞ = 101.71 cm, K = 0.18 y⁻¹, t0 = −0.07 y for males and L_∞ = 106.54 cm, K = 0.16 y⁻¹, t0 = −0.28 y for females. The maximum age was 8 years for males and females. Total length at first maturity of males and females was 70.9 cm and 81.2 cm, respectively. Based on the gonadosomatic index and gonadal macroscopic observations, it was determined that the spawning period lasted throughout the year. Stomach content analysis showed that crustaceans (53.03% IRI) and teleosts (14.70% IRI) were the most preferred prey.

References

Adda-Hanifi, M., Kherraz, A., Mouffok, S. & Boutiba, Z. (2017). Age and growth estimates of thornback ray, Raja clavata (Linnaeus, 1758) in Western Algerian coast (Chondrichthyes, Rajidae). IJB 10(6): 55–68. DOI: 10.12692/ijb/10.6.55-68.
Open DOI Search in Google Scholar Back to article
Bertalanffy, L.V. (1938). A quantitative theory of organic growth (Inquiries on growth laws. II.). Hum. Biol. 10: 181–213.
Search in Google Scholar Back to article
Borges C.T., Olim, S. & Erzini, K. (2003). Weight-length Relationships for Fish Species Discarded in Commercial Fisheries of the Algorve (souther Portual). J. Appl. Ichthyol. 19: 394–396. DOI: 10.1111/j.1439-0426.2003.00480.x.
Open DOI Search in Google Scholar Back to article
Bök, D.T., Göktürk, D., Kahraman, E.A., Alıçlı, Z.T., Acun, T. et al. (2011). Length Weight Relationships of 34 Fish Species from the Sea of Marmara Turkey. J. Anim. Vet. Adv. 10(23): 3037–3042. DOI: 10.3923/javaa.2011.3037.3042.
Open DOI Search in Google Scholar Back to article
Braccini, J.M. & Chiaramonte, G.E. (2002). Reproductive biology of Psammobatis extenta. J. Fish Biol. 61: 272–288. DOI: 10.1006/jfbi.2002.204.
Open DOI Search in Google Scholar Back to article
Brander, K. & Palmer, D. (1985). Growth rate of Raja clavata in the Northeast Irish Sea. Journal du Conseil – Conseil International pour l' Exploration de la Mer 42: 125–128.
Search in Google Scholar Back to article
Campana, S.E. (2014). Age determination of elasmobranchs, with special reference to Mediterranean species: a technical manual. Studies and Reviews. General Fisheries Commission for the Mediterranean. No. 94. Rome, FAO 2014. 38 p.
Search in Google Scholar Back to article
Cannizzaro, L.G., Garofalo Rizzo, L.D. & Gancitano, S. (1995). Raja clavata in the Sicilian Channel: Growth, distribution, abundance. Biol. Mar. Mediterr. 2: 257–262.
Search in Google Scholar Back to article
Capapè, C., Guélorget, O., Siau, Y., Vergne, Y. & Quignard, J.P. (2007). Reproductive biology of the thornback skate Raja clavata (Chondrichthyes: Rajidae) from the coast of Languedoc (Southern France, Northern Mediterranean). Vie et Milieu – Life and Environment 57: 83–90.
Search in Google Scholar Back to article
Capapé, C. & Quignard, J.P. (1974). Contribution à la biologie des Rajidae des côtes tunisiennes. 1. Raja miraletus, Linné, 1758: répartition géographique et bathymétrique, sexualité, reproduction, fécondité. Archives de Ínstitut Pasteur Tunis 51: 39–60.
Search in Google Scholar Back to article
Carlander, K.D. (1969). Handbook of freshwater fishery biology, volume 1. The Iowa State University Press, Ames: Iowa.
Search in Google Scholar Back to article
Carlander, K.D. (1977). Handbook of freshwater fishery biology 2. Life history data on centrarchidfishes of the United States and Canada. – Iowa State University Press, Ames, Iowa.
Search in Google Scholar Back to article
Demirhan, A.S., Engin, S., Seyhan, K. & Akamca, E. (2005). Some Biological Aspects of Thornback Ray (Raja clavata L., 1758) in the Southeastern Black Sea. Turk. J. Fish. Aquat. Sci. 5: 75–83.
Search in Google Scholar Back to article
Dulvy, N.K. & Reynolds John, D. (1997). Evolutionary transitions among egg–laying, live–bearing and maternal inputs in sharks and rays. Proceedings of the Royal Society B: Biological Sciences 264 (1386): 1309–1315. DOI: 10.1098/rspb.1997.0181.
Open DOI Search in Google Scholar Back to article
Du Buit, M.H. (1976). The ovarian cycle of the cuckoo ray, Raja naevus (Müller and Henle), in the Celtic Sea. J. Fish Biol. 8: 199–207. DOI: 10.1111/j.1095-8649.1976.tb03943.x.
Open DOI Search in Google Scholar Back to article
Ebeling, E. (1988). A brief survey of the feeding preferences of Raja clavata in Red Wharf Bay in the Irish Sea. p. 1–5 plus tables. ICES C.M. 1988/G:58, Demersal Fish Committee.
Search in Google Scholar Back to article
Ebert, D.A., Smith, W.D. & Cailliet, G.M. (2008). Reproductive biology of two commercially exploited skates, Raja binoculata and R. rhina, in the western Gulf of Alaska. Fish. Res. 94: 48–57.
Search in Google Scholar Back to article
Ebert, D.A. (2005). Reproductive biology of skates, Bathyraja (Ishiyama), along the eastern Bering Sea continental slope. J. Fish Biol. 66: 618–649.
Search in Google Scholar Back to article
Ellis, J.R., Pawson, M.G. & Shackley, S.E. (1996). The comparative feeding ecology of six species of shark and four species of ray (Elasmobranchii) in the North-East Atlantic. J. Mar. Biol. Assoc. U.K. 76: 89–106. DOI: 10.1017/S0025315400029039.
Open DOI Search in Google Scholar Back to article
Ellis, J.R. & Shackley, S.E. (1995). Observations on egg-laying in the thornback ray. J. Fish Biol. 46(5): 903–904. DOI: 10.1111/j.1095-8649.1995.tb01613.x.
Open DOI Search in Google Scholar Back to article
Fahy, E. (1991). The south eastern ray Raja spp. fishery, with observations on the growth of rays in Irish waters and their commercial grading. Irish Fisheries Investigations Series B, No. 37, 17pp.
Search in Google Scholar Back to article
Farias, I., Figueiredo, I., Moura, T., Gordo, S.L., Neves, A. et al. (2006). Diet Comparison of Four ray Species (Raja clavata, Raja brachyura, Raja montagiu and Leucoraja naevus) Caught Along the Portuguese Continental Shelf. Aquat. Living Resour. 19: 105–114. DOI: 10.1051/alr:2006010.
Open DOI Search in Google Scholar Back to article
Filiz, H. & Mater, S. (2002). A Preliminary Study on Lenght-Weight Relationships for Seven Elasmobranch Species from North Aegean Sea, Turkey. EgeJFAS 19(3–4): 401–409.
Search in Google Scholar Back to article
Fischer, W. (1973). FAO Species Identification Sheets for Fishery Purposes, Mediterranean and Black Sea. In W. Fıscher (Ed.), Fishing Area 37 Volume II. FAO of the UN Rome.
Search in Google Scholar Back to article
Fischer, W., Bauchot, M.L. & Schnider, M. (1987a). Fishes FAO d’identification des espe’ces pour lesw besoins de la pe’che. (Re’vision 1). Me’diterrenele et mer Noir. Zone de pe’che 37. Vol. I. Ve’ge’taux et inverte’bre’s. Publication pre’pare’e par la FAO, re’sultat du’n accord entra la FAO et la Commission des Communaute’s Europe’ennes (Project GCP/INT/422/EEC) finance’e conjointement par ces deux organizations. Rome, FAO, Vol.1.
Search in Google Scholar Back to article
Fischer, W., Bauchot, M.L. & Schnider, M. (1987b). Fishes FAO d’identification des espe’ces pour lesw besoins de la pe’che. (Re’vision 1). Me’diterrenele et mer Noir. Zone de pe’che 37. Vol. I. Ve’ge’taux et inverte’bre’s. Publication pre’pare’e par la FAO, re’sultat du’n accord entra la FAO et la Commission des Communaute’s Europe’ennes (Project GCP/INT/422/EEC) finance’e conjointement par ces deux organizations. Rome, FAO, Vol.2: 761–1530.
Search in Google Scholar Back to article
Gallagher, S., Marras, W.S., Litsky, A.S. & Burr, D. (2005). Torso flexion loads and fatigue failure of human lumbosacral motion segments. Spine 30: 2265–2273. DOI: 10.1097/01.brs.0000182086.33984.b3.
Open DOI Search in Google Scholar Back to article
Hamlett, W.C. & Koob, T.J. (1999). Female reproductive system. In W.C. Hamlett (Ed.), Sharks, Skates and Rays (pp. 398–443). Baltimore, The John Hopkins University Press.
Search in Google Scholar Back to article
Holden, M.J., Rout, D.W. & Humphreys, N. (1971). The rate of egg laying by three species of ray. Journal du Conseil International pour I'Exploration de la Mer 33(3): 335–339. DOI: 10.1093/icesjms/33.3.335.
Open DOI Search in Google Scholar Back to article
Holden, M.J. (1972). The Growth Rates of Raja Brachyura, R. Clavata and R. Montagui as Determined From Tagging Data. Journal du Conseil International pour l'Exploration de la Mer 34(2): 161–168. DOI: 10.1093/icesjms/34.2.161.
Open DOI Search in Google Scholar Back to article
Holden, M.J. (1975). The Fecundity of Raja clavata in British Waters. ICES J. Mar. Sci. 36(2): 110–118. DOI: 10.1093/icesjms/36.2.110.
Open DOI Search in Google Scholar Back to article
Holden, M.J. & Raitt, D.F.S. (1974). Manual of Fisheries science. Part 2: Methods of Resource Investigation and Their Application. FAO Fisheries Technical Report 115(1).
Search in Google Scholar Back to article
Hyslop, E.J. (1980). Stomach Content Analysis- A Review of Methods and Their Application. J. Fish Biol. 17: 411–429. DOI: 10.1111/j.1095-8649.1980.tb02775.x.
Open DOI Search in Google Scholar Back to article
Ilkyaz, A.T., Metin, G., Soykan, O. & Kinacigil, H.T. (2008). Length–weight relationship of 62 fish species from the Central Aegean Sea, Turkey. J. Appl. Ichthyol. 24: 699–702. DOI: 10.1111/j.1439-0426.2008.01167.x.
Open DOI Search in Google Scholar Back to article
İşmen, A., Özen, Ö., Altınağaç, U., Özekinci, U. & Ayaz, A. (2007). Weight–length relationships of 63 fish species in Saros Bay. Turkey. J. Appl. Ichthyol. 23: 707–708. DOI: 10.1111/j.1439-0426.2007.00872.x.
Open DOI Search in Google Scholar Back to article
Jardas, I. (1973). A contribution to our knowledge of the biology and ecology of thornback ray (Raja clavata L.) and brown ray (Raja miraletus L.) in the Adriatic. Acta Adriat. 15: 1–42.
Search in Google Scholar Back to article
Janez, J.A. & Sueiro, M.C. (2009). Oviposition rate of the fanskate Symterygia bonapartii (Elasmobranchii, Rajidae) (Müller & Henle, 1841) held in captivity. Pan-Am. J. Aquat. Sci. 4(4): 580–582.
Search in Google Scholar Back to article
Kadri, H., Marouani, S. Saïdi, B., Bradi, N.M., Bouaïn, A. et al. (2014a). Age, Growth, Sexual Maturity and Reproduction of the Thornback ray, Raja clavata (L.) of the Gulf of Gabes (South-central Mediterrannean Sea). Mar. Biol. Res. 10(4): 416–425. DOI: 10.1080/17451000.2013.797584.
Open DOI Search in Google Scholar Back to article
Kadri, H., Marouani, S., Bradai, N.M. & Bouain, A. (2014b). Diet and Feeding Strategy of Thornback ray, Raja clavata (Chondrichthyes: Rajidae) from the Gulf of Gabes (Tunisia – Central Mediterranean Sea). J. Mar. Biol. Assoc. U.K. 94(7): 1509–1516. DOI: 10.1017/S0025315414000587.
Open DOI Search in Google Scholar Back to article
Karachle, K.P. & Stergiou, I.K. (2010). Food and Feeding Habits of Nine Elasmobranch Species in the North Aegean Sea. Rapp. Comm. İnt. Mer Medit. 39.
Search in Google Scholar Back to article
Kusher, D.I., Smith, S.E. & Cailliet, G.E. (1992). Validated age and growth of the leopard shark, Triakis semifasciata, with comments on reproduction. Environ. Biol. Fishes 35: 187–203.
Search in Google Scholar Back to article
Lesser, J.H.R. (1967). Studies on ray stocks of the southeastern Irish Sea. Unpublished MSc Thesis, University of Wales, Bangor Wales.
Search in Google Scholar Back to article
Maia, C., Serra-Pereira, B., Erzini, K. & Figueiredo, I. (2015). How is the Morphology of the Oviducal Gland and of the Resulting Egg Capsule Associated with the Egg Laying Habitat of Rajidae Species? Environ. Biol. Fishes 98: 2037–2048. DOI:10.1007/s10641-0150425-1.
Open DOI Search in Google Scholar Back to article
Marquardt, D. (1963). An Algorithm for Least-Squares Estimation of Nonlinear Parameters. SIAM J. Appl. Math. 11: 431–441.
Search in Google Scholar Back to article
Mendes, B., Fonseca, P. & Campos, A. (2004). Weight-length Relationships for 46 Fish Species of the Portuguese West Coast. J. Appl. Ichthyol. 20: 355–361. DOI: 10.1111/j.1439-0426.2004.00559.x.
Open DOI Search in Google Scholar Back to article
Morato, T., Solá, E., Grós, P.M. & Menezes, G. (2003). Diets of Thornback ray (Raja clavata) and Tope Shark (Galeorhinus galeus) in the Bottom Longline Fishery of the Azores, Northeastren Atlantic. NMFS Scientific Publications Office. Fish. Bull. 101: 590–602.
Search in Google Scholar Back to article
Murduchay-Boltouski, F.D. (1969). Detection of Black Sea and Azov Sea Fauna. In V.A. Volyaniski (Ed.). vol. 3.
Search in Google Scholar Back to article
Oddone, M.C. & Vooren, C.M. (2005). Reproductive biology of Atlantoraja cyclophora (Regan 1903) (Elasmobranchii: Rajidae) off southern Brazil. ICES J. Mar. Sci. 62: 1095–1103. DOI: 10.1016/j.icesjms.2005.05.002.
Open DOI Search in Google Scholar Back to article
Oddone, M.C. & Velasco, G. (2004). Size at maturity of the smallnose fanskate Sympterygia bonapartii (Muller and Henle, 1841) (Pisces, Elasmobranchii, Rajidae) in the SW Atlantic. ICES J. Mar. Sci. 61: 294–297. DOI: 10.1016/j.icesjms.2003.11.004.
Open DOI Search in Google Scholar Back to article
Paesch, L. & Oddone, M.C. (2008). Change in size-at-maturity of the yellownose skate Dipturus chilensis (Guichenot, 1848) (Elasmobranchii: Rajidae) in the SW Atlantic. Neotrop. Ichthyol. 6: 223–230. DOI: 10.1590/S1679-62252008000200009.
Open DOI Search in Google Scholar Back to article
Pawson, M. & Vince, M. (1999). Management of shark fisheries in the northeast Atlantic. In R. Shotton (Ed.), Case Studies of the Management of Elasmobranch Fisheries. Rome: FAO Fisheries Technical Paper 1: 1–46.
Search in Google Scholar Back to article
Pawson, M.G. & Ellis, R.J. (2005). Stock Identity of Elasmobranchs in the Northeast Atlantic in Relation to Assessment and Management. J. Northwest Atl. Fish. Sci. 35: 173–193. DOI: 10.2960/J.v35.m480.
Open DOI Search in Google Scholar Back to article
Pinkas, L.M., Oliphant, S. & Iverson, I.L.K. (1971). Food habits of albacore, bluefin tuna, and bonito in Californian waters. State of California the Resources Agency Department of Fish and Game, Fish Bulletin 152: 1–105.
Search in Google Scholar Back to article
Prager, M.H., Saila, S.B. & Recksiek, C.W. (1987). FISHPARM: A microcomputer program for parameter estimation of nonlinear models in fishery science. Old Dominion University, Norfolk, Virginia, Technical Report (87–10): 1–37.
Search in Google Scholar Back to article
Quiniou, L. & Rabarison, A.G. (1979). Variations du regime alimentaire de raies de la baie de Douarnenez (Raja montagui Fowler, 1910; Raja brachyura Lafont, 1873; Raja clavata L., 1758). Cybium 3^e série 7: 27–39.
Search in Google Scholar Back to article
Rosa, A., Menezes, G., Melo, O. & Pinho, R.M. (2006). Weight-length relationships of 33 demersal fish species from Azores archilago. Depertamento de Oceanografia e Pescas, Universidade dos Açores, PT-9901-862 Horta, Portugal.
Search in Google Scholar Back to article
Ryland, S.J. & Ajayi, O.T. (1984). Growth and Population Dynamics of Three Raja Species (Batoidei) in Carmarthen Bay, British Isles. ICES Journal of Marine Science 41(2): 111–120.
Search in Google Scholar Back to article
Sağlam, H. & Ak, O. (2012). Reproductive Biology of Raja clavata (Elasmobranchii: Rajidae) from Southern Black Sea Coast Around Turkey. Helgol. Mar. Res. 66: 117–126.
Search in Google Scholar Back to article
Sağlam, H. & Başçınar, S.N. (2008). Feeding Ecology of Thornback ray (Raja clavata Linnaeus, 1758) on the Turkish Coast of the South-Eastern Black Sea. Mar. Biol. Res. 4: 451–457. DOI: 10.1080/17451000802233393.
Open DOI Search in Google Scholar Back to article
Šantić, M., Rada, B. & Pallaoro, A. (2012). Diet and Feeding Strategy of Thornback ray Raja clavata. J. Fish Biol. 81: 1070–1084. DOI: 10.1111/j.1095-8649.2012.03382.x.
Open DOI Search in Google Scholar Back to article
Serra-Pereira, B., Figueiredo, I., Bordalo-Machado, P., Farias, I., Moura, T. et al. (2005). Age and Growth of Raja clavata Linnaeus, 1758 – Evaluation of Ageing Precision Using Different Types of Caudal Denticles. ICES CM Elasmobranch Fisheries Science N:17.
Search in Google Scholar Back to article
Serra-Pereira, B., Afonso, F., Farias, I., Joyce, P., Ellis, M. et al. (2011). The development of the oviducal gland in the rajid thornback ray, Raja clavata, Helgol. Mar. Res. DOI: 10.1007/s10152-010-0232-1.
Open DOI Search in Google Scholar Back to article
Skomal, G.B. & Natanson, L.J. (2003). Age and growth of the blue shark, (Prionace glauca) in the North Atlantic Ocean. Fish. Bull. 101: 627–639.
Search in Google Scholar Back to article
Smale, M.J. & Cowley, P.D. (1992). The feeding ecology of skates (Batoidea: Rajidae) off the Cape South coast, South Africa. South Afr. J. Mar. Sci. 12: 823–834. DOI: 10.2989/02577619209504744.
Open DOI Search in Google Scholar Back to article
Sparre, P. & Venema, S.C. (1992). Introduction to tropical fish stock assessment. Part 1. Manual FAO Fisheries Technical Paper No: 306/1, Rev. 1, 376.
Search in Google Scholar Back to article
Stehmann, M. & Bürkel, D.L. (1984). Rajidae. In P.J.P. Whitehaed, M.-L. Bauchot, J.-C. Hureau, J. Nielsen & E. Tortonese (Eds.), Fishes of the North-eastern Atlantic and the Mediterranean (pp. 163–196). Vol. I, UNESCO.
Search in Google Scholar Back to article
Tanaka, S., Cailliet, G.M. & Yudin, K.G. (1990). Differences in growth of the blue shark, Prionace glauca: Technique or population? In H.L. Pratt, S.H. Gruber & T. Taniuchi (Eds.) Elasmobranchs as Living Resources: Advances in the Biology, Ecology, Systematics, and the Status of the Fisheries. NOAA Technical Report NMFS 90: 177_87.
Search in Google Scholar Back to article
Taylor, A.J. & Holden, M.J. (1964). The preparation and use of vertebrae for age determination in ray. Vol. 145 ICES Document CM near Northern Seas Committee, pg. 4.
Search in Google Scholar Back to article
Templeman, W. (1987). Differences in sexual maturity and related characteristics between populations of thorny skate (Raja radiata) from the Northwest Atlantic. J. Northwest Atl. Fish. Sci. 7: 155–167.
Search in Google Scholar Back to article
Torres, B., Morey, G. & Tomas, J. (2005). Interpretation of vertebral growth marks as annuli in the sandbar shark Carcharhinus plumbeus: Analysis of vertebrae of captive specimens. J. Mar. Biol. Assoc. U.K. 85: 1167–1170.
Search in Google Scholar Back to article
Tüik, 2018. Türkiye İstatistik Kurumu, Su Ürünleri İstatistikleri https://biruni.tuik.gov.tr/medas/?kn=97&locale=tr. (In Turkish).
Search in Google Scholar Back to article
Valls, M., Quetglas, A., Ordines, F. & Moronta, J. (2011). Feeding ecology of demersal elasmobranchs from the shelf and slope off the Balearic Sea (western Mediterranean). Sci. Mar. 75(4): 633–639.
Search in Google Scholar Back to article
Walker, P.A. (1999). Fleeting images. Dynamics of North Sea ray populations. Unpublished doctoral dissertation. University of Amsterdam.
Search in Google Scholar Back to article
Wheeler, A. (1978). Key to the fishes of northern Europe. Frederick Warne, London.
Search in Google Scholar Back to article
Whitehead, P.J.P., Bauchot, M.L., Hureau, J.C., Nielsen, J. & Tortonese, E. (Eds) (1986a). Fishes of the North-Eastern Atlantic and the Mediterranean. Vol. 1. Richard Clay Ltd, UK: 511–1007.
Search in Google Scholar Back to article
Whitehead, P.J.P., Bauchot, M.L., Hureau, J.C., Nielsen, J. & Tortonese, E. (Eds) (1986b). Fishes of the North-Eastern Atlantic and the Mediterranean. Vol. 2. Richard Clay Ltd, UK: 1008–1474.
Search in Google Scholar Back to article
Whittamore, M.J. & McCarthy, D.I. (2005). The Population Biology of the Thornback ray, Raja clavata in Caernarfon Bay, North Wales. J. Mar. Biol. Assoc. U.K. 85: 1089–1094. DOI: 10.1017/S0025315405012130.
Open DOI Search in Google Scholar Back to article
Windell, J.T. & Bowen, S.H. (1978). Methods for The Study of Fish Diets Based on Analysis of Stomach contents. In T. Bagnel (Ed.), Methods for the Assessment of Fish Production in Fresh Waters. 3rd edn. Oxford: Blackwell.
Search in Google Scholar Back to article
Yeldan, H., Avşar, D. & Manaşırlı, M. (2008). Kuzeydoğu Akdeniz’deki Deniz Tilkisi Raja clavata (Linnaeus, 1758)’nın Bazı Biyolojik Özellikleri. EgeJFAS 25(3): 221–228.
Search in Google Scholar Back to article
Yemişken, E. (2017). Doğu Akdeniz Balıkçılık Bölgelerinde Trol Balıkçılığının Kıkırdaklı Balık Türleri Üzerine Etkisinin Karşılaştırılması. Unpublished doctoral dissertaton. İstanbul Üniversitesi, Türkiye. (In Turkish).
Search in Google Scholar Back to article
Yığın, C.Ç. & İşmen, A. (2009). Lenght-Weight Relationship for Seven Rays from Saros Bay (North Aegean Sea). J. Appl. Ichthyol. 25: 106–108. DOI: 10.1111/j.1439-0426.2008.01161.x.
Open DOI Search in Google Scholar Back to article
Yığın C.Ç. & İşmen, A. (2010). Diet of Thornback ray (Raja clavata Linnaeus, 1758) in Saros Bay (The North Aegean Sea). Rapp. Comm. Int. Mer Médit. 39.
Search in Google Scholar Back to article

Biology of the thornback ray (Raja clavata Linnaeus, 1758) in the North Aegean Sea

Abstract

Paradigm

My account