International Journal of Agricultural Policy and Research
Vol.2 (4), pp. 132-140, April 2014
Article ID JPR015/14/09 pages
Copyright © 2014 Author(s) retain the copyright of this article. Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 3.0 International License
Original Research Paper
Biological aspects and yield of the shrimp Parapenaeus longirostris, West Africa
Accepted 27 February, 2014
1*Sankare Yacouba, 2Sohou Zaccharia and 1Tape Joanny
1Centre de Recherches Océanologiques 29 Rue des Pêcheurs, BPV 18 Abidjan, Côte D’Ivoire.
2Institut de Recherches Halieutiques et Océanologiques du Bénin (IRHOB) 03 BP 1665 Cotonou, Benin.
*Corresponding Author’s Email: sankare811(at)yahoo.fr
Tel. : +(225) 07 77 11 84
Fax : +(225) 21 35 11 55
This study within 12 months (January-December) examined the growth, mortality rates and recruitment pattern of exploited deep-water rose shrimp Parapenaeus longirostris (Lucas, 1846) in Ivorian marine waters. Length-frequency samples and FISAT software (which incorporates both the ELEFAN and LSFA programs) was used for the data analysis.A fit of the seasonalized von Bertalanffy growth equation to the Length-frequency data gave the following results: L∞ = 17.61 cm; total length, K=0.784 year-1 and an Rn value of 0.376. The study also estimated the total mortality coefficient Z=4.837year-1 through the seasonalized length-converted catch curve procedure. The instantaneous natural mortality coefficient M was 1.097 year-1 while the instantaneous fishing mortality (F) coefficient was 3.740 year-1. An exploitation rate E of 0.773 implies that the stock is over exploited. The results of the yield-per-recruit analysis lend further credence to this assertion. The distribution of juveniles and ovigerous females in the samples show that there were two reproduction peaks (February and August) and two recruitment peaks (March and September). The results of back-projected length-frequency data set on to an arbitrary one-year scale also show that there were two recruitments in a year.
Key words: Parapenaeus longirostris, deepwater rose shrimps, mortality rates, recruitment, Côte d’Ivoire