Natural diet of deep-water rose shrimp in the Beni-Saf Bay (Western Algeria)

Abstract

The deep-water rose shrimp, Parapenaeus longirostris (Lucas, 1846) is one of the Decapod crustacean species that is targeted by coastal and deep-sea demersal fisheries in the western Mediterranean, in the Algerian west coast in particular. Despite its socio-economic importance and commercial interest across the country, there were only few studies focusing on its biology and ecology and no species development plan has been drawn up for now. Our study of the rose shrimp diet was based on the analysis of the faunistic composition of the ingested prey. Seasonal sampling was carried out at Beni Saf port (western Algeria) during 2018-2019, from landings from inshore trawling fisheries. A total of 641 individuals were analyzed, while taking account of males and females and size classes. Results of stomach content analyzes showed a wide range of benthic and endobenthic species. Crustacea are the preferred prey (F=77.69%), followed by Foraminifera, Annelida Polychaeta, and Mollusca with respective frequencies of (77.22%, 58.50% and 52.73%). Radiolaria, Porifera and Echinodermata represent a less important part in the diet of this species and constitute accidental prey, whose frequency is less than 10%. Benthic organisms with silt ingest the plant and various debris, which are the secondary prey with an average frequency of 14.81%.