International Journal of Agricultural Policy and Research
Vol.3 (7), pp. 300-307,July 2015
Available online at https://www.journalissues.org/IJAPR/
Article 15/ID/JPR059/08/ pages
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License.
Original Research Article
The dynamics of population of Alestes nurse (African Pink) in Gubi Dam – Nigeria using simplified empirical models
Yusuf Z.A.1 and *Abdulkarim M.2
1Department of Biological Sciences, Faculty of Science, Abubakar Tafawa Balewa University, Bauchi, Bauchi State, Nigeria.
2Department of Animal Production, Faculty of Agriculture and Agricultural Technology in Abubakar Tafawa Balewa University, Bauchi, Bauchi State, Nigeria.
*Corresponding Author E-mail:mashemau(at)yahoo.com
Length – frequencies data (LFD) were extensively collected on Alestes nurse (African pink) fish in Gubi dam for a period of one year as to study the population dynamics of the stock. The samples of LFD were adjusted against biasness using an empirical method since they were obtained from commercial catches fished with gill nets. The LFD were analysed with simplified empirical models such as ABC – DU Y/R Model and new empirical methods used for estimating total mortality (Z), that was developed alongside with introduction of new concepts: Net Reproductive Rate (Ro) and Maximum Recruit (R∞) into fisheries stock assessment. The analysis shows that population parameters: growth coefficient K = 1.21/year; mortality rates – natural (M), fishing (F) and Z are 2.22/year, 0.47/year and 2.69/year respectively while the stock status indicates that A. nurse is productive and resilient with exploitation rate, E = 0.17. However, current annual effort, fA = 49,388 man days should be increased by 17.65% so as to attain maximum sustainable yield of 646,388, 485.4g.
Key words: Alestes nurse, population parameters, stock status, empirical models, Gubi dam