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Polychaetes tend to form the dominant sediment dwelling fauna of the most mudflats, estuaries and sheltered sandy shores and it also play a significant role in ecosystem functioning and services. Seasonal changes in the length, fresh weight, oocyte diameter, sexual status and sexual maturity index of the polychaete Perinereis cultrifera (Grube, 1840) (Anellida Polychaeta Nereididae) were studied during twelve months from January to December 2016 in the east coast of Algeria. The samples were collected monthly at three sites: El-Kala, a site far from any source of pollution, Annaba and Skikda, sites located near human and industrial wastes. The reproductive cycle of the females was studied; however, the ovaries consist of coelomic germ-cell clusters surrounded by a thin envelope of follicle cells. The female coelomic puncture has a heterogeneous aspect and shows different oocyte diameters. The reproductive period is more intense in spring period. The results show differences between sites compared with the reference samples. The reproduction period of occurs in spring (April, May). This approach confirms that individuals collected from Annaba and Skikda have been submitted to a highly polluted environment. Therefore, individuals sampled from Skikda showed the highest reduction of different measured parameters.

Effects of environmental stress on the growth and the reproduction of Perinereis cultrifera (Annelida Polychaeta) from the eastern coasts of Algeria