Feeding Ecology of Perinereis Cultrifera (Grube, 1840) On Eastern Coastline of Algeria

Polychaetes are naturally important components of the food webs of aquatic ecosystems. Perinereis cultrifera (Annelida: Polychaeta), a benthic species characterized by wide geographic distribution, has economic importance because it is used as bait in recreational fishing and as a food source in aquaculture. The feeding ecology of Perinereis cultrifera was studied over 12 months at three sites on the northeast coast of Algeria; a total of 1192 guts were observed. The investigation revealed that diet changed slightly according to the sampling site, season, and specimen sizes (larger individuals ingest more algae and polychaete) with a preference of P.cultrifera to green algae. In all sampling stations, a total of twelve items were found, but only five shown an occurrence superior to 3%. These were: mucus (51%), sand (15.6%), vegetable detritus (17.2%), Nereididae (6.7%) and Crustaceans (3.8%). No difference in digestive contents between sexes despite the evidence of higher carnivore behaviour for the males of Perinereis cultrifera than females. Individuals from El Kala (reference site) had bigger weight, length, and differentiated sexes comparing with Annaba and Skikda where the degree of pollution is more consequent.