Seasonal and inter-annual variations in the density of the invasive polychaete Streblospio gynobranchiata were noted in the south Caspian Sea when sediment conditions were examined at five and 14 meters depths in 2005 and 2010. There was no clear trend in changing density in line one but in line two, in all seasons except summer, density of S. gynobranchiata decreased significantly. Maximum densities of 2,040 ind./m−2 and 1,013 ind./m−2 were obtained in 2005 and 2010, respectively. Although the percentage of total organic matter as a food resource increased from 2005 to 2010, the density of S. gynobranchiata decreased slightly in the same period. It seems that in this invasion phase the population of S. gynobranchiata has decreased to a balance condition. There is evidence that the changing density of this species is also being affected by other biotic/abiotic factors like intra/interspecific competitors and pollutants.
1. Anderson M. J. and Robinson J., 2003 − Generalized discriminant analysis based on distances, Australian and New Zealand Journal of Statistics, 45, 301-318.
2. Boltacheva N. A., 2008 − Finding of new alien species Streblospio gynobranchiata Rice and Levin, 1998 (Polychaeta: Spionidae) in the Black Sea, Marine Ecological Journal, 7, 4, 12-13.
3. Cinar M. E., Ergen Z., Dagli E. and Petersen M. E., 2005 − Alien species of spionid polychaetes (Streblospio gynobranchiata and Polydora cornuta) in Izmir Bay, Mediterranean, Journal of the Marine Biological Association of the United Kingdom, 85, 821-827.
4. Cinar M. E., Katagan T., Ozturk B., Egemen O., Ergen Z., Kocatas A., Onen M., Kirkim F., Bakir K., Kurt G., Dagli E., Kaymakci A., Acik C., Dogan A. and Ozcan T., 2006 − Temporal changes of soft-bottom zoobenthic communities in and around Alsancak Harbour (Izmir Bay, Aegean Sea), with special attention to the autecology of exotic species, Marine Ecology, 27, 229-246.
5. Crooks J. A., 2001 − Assessing invader roles within changing ecosystems: historical and experimental perspectives on an exotic mussel in an urbanized lagoon, Biological Invasions, 3, 23-36.
6. Essink K. and Dekker R., 2002 − General patterns in invasion ecology tested in the Dutch Wadden Sea: the case of a brackish-marine Polychaetous worm, Biological Invasions, 4, 359-368.
7. Fereidouni S., Modir Rousta H. and Azin F., 2006 − The First Report of Avian Cholera in Miankaleh Wetland, Southeast Caspian Sea, Podoces, 1, 71-75.
8. Garcia-Arberas L. and Rallo A., 2004 − Population dynamics and production of Streblospio benedicti (Polychaeta) in a non-polluted estuary on the Basque coast (Gulf of Biscay), Scientia Marina, 68, 2, 193-203.
9. Hadjizadeh Zaker N., Ghafari P. and Jamshidi S., 2007 − Physical study of the southern coastal waters of the Caspian Sea, off Babolsar, Mazandaran in Iran, Journal of Coastal Research, 50, 564-569.
10. Karbassi A. R. and Amirnezhad R., 2004 − Geochemistry of heavy metals and sedimentation rate in a bay adjacent to the Caspian Sea, International Journal of Environmental Science and Technology, 1, 191-198.
11. Kideys A. E., Roohi A., Eker-Develi E., Mélin F. and Beare D., 2008 − Increased Chlorophyll Levels in the Southern Caspian Sea Following an Invasion of Jellyfish, Research Letters in Ecology Article, ID 185642, 4.
13. MacMahan J. H., Thornton E. B., Stanton T. P. and Reniers H. M., 2005 − RIPEX: observation of a rip current system, Marine Geology, 218, 113-134.
14. McLachlan A. and Hesp P., 1984 − Faunal response to morphology and water circulation of a sandy beach with cusps, Marine Ecology Progress Series, 19, 133-144.
15. Neideman R., Wenngren J. and Ólafsson E., 2003 − Competition between the introduced polychaete Marenzelleria sp. and the native amphipod Monoporeia affinis in Baltic soft bottoms, Marine Ecology Progress Series, 264, 49-55.
16. Norkko J. Reed D. C., Timmermann K., Norkko A., Gustafsoon B. G., Bonsdorff E., Slomp C. P., Carstensen J. and Conley D. J., 2011 − A welcome can of worms? Hypoxia mitigation by an invasive species, Global Change Biology, 18, 2, 422-434.
17. Rice A. S. and Levin L. A., 1998 − Streblospio gynobranchiata, a new spionid polychaete species (Annelida: Polychaeta) from Florida and the Gulf of Mexico with an analysis of phylogenetic relationships within the genus Streblospio, Proceeding of the Biological Society of Washington, 111, 694-707.
18. Roohi A., Kideys A. E., Sajjadi A., Hashemian A., Pourgholam R., Fazli H., Khanari A. and Eker-Develi E., 2010 − Changes in biodiversity of phytoplankton, zooplankton, fishes and macrobenthos in the Southern Caspian Sea after the invasion of the ctenophore Mnemiopsis Leidyi, Biological Invasions, 12, 2343-2361.
19. Rossi F. and Lardiccii C., 2002 − Role of nutritive value of sediment in regulating population dynamics of the deposit-feeding Polychaeta streblospio shrubsolii, Marine Biology, 140, 1129-1138.
20. Shafiei Sabet B. and Barani G. A., 2011 − Field investigation of rip currents along the southern coast of the Caspian Sea, Scientia Iranica, 18, 4, 878-884.
21. Taheri M., Seyfabadi J., Abtahi B. and Yazdani Foshtomi M., 2009 − Population changes and reproduction of an alien spionid polychaete, Streblospio gynobranchiata, in shallow waters of the south Caspian Sea, Marine Biodiversity Records, 2, 40.
22. Taheri M. and Yazdani Foshtomi M., 2011 − Community structure and biodiversity of shallow water macrobenthic fauna at Noor coast, South Caspian Sea, Iran, Journal of the Marine Biological Association of the United Kingdom, 91, 607-613.
23. Taheri M., Yazdani Foshtomi M., Noranian M. and Mira S. S., 2011 − Annelida Community Structure in the Gorgan Bay, Southeast of Caspian Sea, Iran - A Case Study, World Journal of Fish and Marines Sciences, 3, 5, 414-421.
24. Taheri M., Yazdani Foshtomi M., Noranian M. and Mira S. S., 2012 − Spatial Distribution and Biodiversity of Macrofauna in the Southeast of the Caspian Sea, Gorgan Bay in Relation to Environmental Conditions, Ocean Science Journal, 47, 2, 113-122.