Scientific Online Resource System

Journal of the Union of Scientists - Varna. Maritime Sciences Series

Morphometric, quantitative and population characteristics oF Rapana venosa (Valenciennes, 1846) in front of Pasha Dere

Antoaneta Trayanova


A total of 468 individuals of the rapa whelk (Rapana venosa) were studied in terms of size, weight and sex in the sea area in front of Pasha dere (south of Varna Bay, Black Sea) in the summer of 2016. Sampling was performed by bottom trawling on three transects at different depths (from 9.0 m to 24.5 m) and different type of substrate (sand, sandy silt and silt). In the present study the average length was 6.36 cm and the absolute shell length ranged from a minimum of 3.24 cm to a maximum of 9.68 cm. The established average total weight was 47.31 g, its absolute value ranging from 9.98 g to 135.02 g. The average values of the shell length and total weight of the rapa whelk were the lowest on shallow sandy bottom (6.01 cm and 41.94 g, respectively) and the highest at 21 m depth on silty sediments (6.84 cm and 55.13 g, respectively). The size-weight relationship between all individuals was described by the formula W = 0.248L2.797 (R2 = 0.937), with the allometric coefficient (b) ranging from 2.817 to 3.066. On the sandy sediment, the male: female ratio was 2:1; in sandy silt, the percentages of male and female specimens were 55% and 45% respectively, and in silty sediment the sex ratio was 1:1. The male specimens were characterized by higher values of all morphometric parameters compared to the females. In the size distribution of sexes, the highest was the frequency of the males in size class of 6-7 cm, and the females with 5-6 cm shell length. In the weight distribution of the males, the individuals with total weight in the range 30-40 g dominated, while the prevailing female individuals weighed between 20 g and 30 g.


invasive species, Rapana venosa, size-weight distribution, population characteristics, Black Sea

Full Text


Bondarev I.P., 2014. Dynamics of Rapana venosa (Valenciennes. 1846) (Gastropoda: Muricidae) population in the Black Sea. International Journal of Marine Science, Vol. 4. No. 03: 42-56.

Chandler E. A., McDowell J. R., Graves J. E., 2008. Genetically monomorphic invasive populations of the rapa whelk, Rapana venosa. Molecular Ecology, 17: 4079-4091.

Choi J.D., Ryu DK., 2009. Age and growth purple whelk. Rapana venosa (Gastropoda: Muricidae) in the West Sea of Korea. Korean J Malacol., 25(3): 189-196.

Chukhchin V.D., 1961. Development of Rapana (Rapana bezoar L) in the Black Sea. Tr Sevastopol Biol St., No. 14: 163-168.

Chung E.Y., Kim S.Y., Park K.H., Parl G.M., 2002. Sexual maturation. spawning and deposition of the egg capsules of the female purple shell. Rapana venosa (Gastopoda: Muricidae). Malacologia, No. 9:1-15.

Daskalov G., Rätz H.J., 2011. Assessment of Black Sea Stocks. JRC Scientific Technical and Economic Committee for Fisheries (STECF), Italy. 216 pp.

Drapkin E., 1963. Effect of Rapana bezoar Linne (Mollusca. Muricidae) on the Black Sea fauna. Doklady Akademii Nauk SSR, 151(3):700-703.

DÏ‹zgÏ‹nes E., Ãœnsal S., Feyzioglu M., 1992. Stock Assessment of veined whelk Rapana thomasiana (Gross, 1861) in Eastern Black Sea. Project number. DEBAG 143/G. p.55, Karadeniz Technical University, Sürmene Marine Sciences Faculty.

Emiral H., 2003. Bio-ecology of Rapa Whelk (Rapana thomasiana) in the Black sea. PhD Thesis. Karadeniz Technical University Institute of Science, 88 pp.

Erkoyuncu I., 1995. Fisheries Biology and Population Dynamics. Ondokuz Mayıs University publication, 265 pp.

Giberto D.A., Bemec C., Schejter L., Schiariti A., Mianzán H.W., Acha E.M., 2006. The invasive Rapa whelk Rapana venosa (Valenciennes 1846): status and potential ecological impacts in the Rio de la Plata estuary, Argentina-Uruguay. J Shellfish Res, 25(3): 919-924.

Gomoiu M., Alexandrov B., Shadrin N., Zaitsev Y., 2002. Black Sea - a recipient, donor and transit area for alien species. p 341-350. In: Invasive aquatic species of Europe. Distribution, impacts and management. Leppakoski E., Olenin S (Eds). Kluwer Academic Publishers, Dordrecht.

Harding J. M., Kingsley-Smith P., Savini D., Mann R., 2007a. Comparison of predation signatures by Atlantic oyster drills (Urosalpinx cinerea Say, Muricidae) and veined rapa whelks (Rapana venosa Valenciennes, Muricidae) in bivalve prey. Journal of Experimental Marine Biology and Ecology, 352: 1-11.

Harding J. M., Mann R. and Kilduff C. W., 2007b. The effects of female size on fecundity in a large marine gastropod Rapana venosa (Muricidae). Journal of Shellfish Research, 26(1): 33-42.

Harding J.M., 2006. Growth and development of veined rapa whelk Rapana venosa veligers. Journal of Shellfish Research, 25(3): 941-946.

Harding J.M., Mann R., 1999. Observations on the biology of the veined Rapa whelk. Rapana venosa (Valenciennes, 1846) in the Chesapeake Bay. Journal of Shellfish Research, 18(1): 9-17.

ICES, 2004. Alien Species Alert: Rapana venosa (veined whelk). Edited by Roger Mann, Anna Occhipinti, and Juliana M. Harding. ICES Cooperative Research Report No. 264, 14 pp.

Kaneva-Abadjieva V., 1958. A new harmful snail along the Bulgarian Black Sea coast. Priroda, 3: 89-91.

Le Cren E.D., 1951. The length-weight relationships and seasonal cycle in gonad weight and condition in perch (Perca fluviatilis), Journal of Animal Ecology, 20, 210-219.

Mann R., Harding J.M., 2000. Invasion of the North American Atlantic coast by a large predatory Asian mollusc. Biological Invasions, 2: 7-22.

Mann R., Harding J.M., 2003. Salinity tolerance of larval Rapana venosa: implications for dispersal and establishment of an invading predatory gastropod on the North American Atlantic coast. Biol. Bull., No. 204: 96-103.

Pastorino G., Penchaszadeh P. E., Schejter L., Bremec C., 2000. Rapana venosa (Valenciennes, 1846) (Mollusca: Muricidae): A new gastropod in South Atlantic waters. Journal of Shellfish Research, 19(2): 897-899.

Pauly D., 1980. A selection of simple methods for the assessment of tropical fish stocks. FOA Fish Circular. No. 729. Rome. 54 pp.

Saglam H., Duzgunes E., 2007. Deposition of egg capsule and larval development of Rapana venosa (Gastropoda: Muricidae) from the south-eastern Black Sea. J. Mar.Biol. Ass. U.K., 87, 953-957.

Saglam H., Düzgünes E., 2014. Biological parameters and feeding behaviour of invasive whelk Rapana venosa Valenciennes, 1846 in the south-eastern Black Sea of Turkey. Journal of Coastal Life Medicine, 2(6): 442-446.

Sahin C., Dϋzgϋnes E., Engin S., Mutlu C., Hacimurtazaoglu N., 2005. Analysis of Age and Growth Parameters of Rapa Whelk (Rapana thomasiana), Turkish Journal of Aquatic Life, 4, 34-38.

Savini D., Castellazzi M., Favruzza M., Occhipinti-Ambrogi A., 2004. The alien mollusc Rapana venosa (Valenciennes, 1846; Gastropoda, Muricidae) in the Northern Adriatic Sea: Population structure and shell morphology. Chemistry and Ecology, 20, Suppl. 1: 411-424.

Sewell J., Pearce S., Bishop J., Evans J. L., 2008. Investigations to determine the potential risk for certain non-native species to be introduced to North Wales with mussel seed dredged from wild seed beds. CCW Policy Research Report No. 06/3. pp 82.

Ãœnsal S., 1989. DoÄŸu Karadeniz de Rapana thomasiana (Gross)`nın Biyolojik Özellikleri, Besin DeÄŸeri ve Beslenme-DeÄŸerlendirilmeleri Ãœzerine AraÅŸtırmalar. KTU Sürmene Deniz Bil. Yük. Ok. 86. 101. 010. 2 Nolu Proje Raporu 47 s.

Uyan O., Aral O., 2003. The larval development stages of the Japanese snail, Rapana thomasiana, Gross [sic] 1861, in the egg capsule. Turk Journal of Zoology, 27: 331-337.

Yang J., Li Q., Kong L., Zheng X., Wang R., 2008. Genetic structure of the veined rapa whelk (Rapana venosa) populations along the coast of China. Biochemical Genetics, 46: 539-548.

Zengin M., 2006. Effects of the Trawl and Snail Fisheries on the Resources of Benthic Macro Fauna in the Middle Black Sea Coast, Samsun, Turkey. 1st Biannual Scientific Conference. Black Sea Ecosystem 2005 and Beyond 1st Biannual Scientific Conference BSERP/BSC, 8-10 May 2006 Istanbul, Turkey.

Zolotarev V., 1996. The Black Sea ecosystem changes related to the introduction of new mollusc species. Marine Ecology, 17 (1-3): 227-236.



Font Size