Population dynamics and yield of the black goby Gobius niger L. in Algeria (Gulf of Annaba)

Abstract

Event Abstract Back to Event Population dynamics and yield of the black goby Gobius niger L. in Algeria (Gulf of Annaba) Abderrahmane Kassar1*, Alaeddine Benallia1, Daoud Bouchelif1 and Farid Hemida1 1 École Nationale Supérieure des Sciences de la Mer et de l'Aménagement du Littoral, Algeria The black goby Gobius niger L., 1758 is a demersal gobiid fish caught by bottom trawl in the Gulf of Annaba (South Western Mediterranean). No published prior studies on its biology, population dynamics or stock assessment has been conducted in Algeria. A monthly sampling of this species has been done between Dec 2015 and May 2016 from commercial catch in order to estimate the growth, mortality and exploitation parameters of the stock for the first time in the Algerian Basin. Maximum total length (TL) and maximum total weight (TW) were 15.3 cm and 43.2 g, respectively. Power function type relationship between length and weight was obtained using 344 couples and it was written as TW = 0.0095*TL^3.0701. Estimated von Bertalanffy growth parameters using ELEFAN I routine in FiSAT II program were as follows: L∞ = 16.03 cm and K = 0.8 year-1. The estimated value of Total Mortality based on length converted catch curve was Z = 1.93 year-1. Natural Mortality calculated using Djabali et al. method (1994) based on the asymptotic length and the growth curvature was M = 0.6 year-1. Computed Fishing Mortality was F = 1.33 year-1. The Thompson & Bell model (1934) was used for stock assessment based on data obtained from Jones analysis (1983). Model estimated Maximum Sustainable Yield was MSY = 9 tonnes that corresponds to a 2.6 F-factor. As the reference yield is 8.5 t, there would be scope only to marginally increase the catch by 5.56%. A doubled fishing effort would increase the catch by 7%. Exploitation rate is at its optimum and the applied model recommends maintaining the actual catch. It could also be reduced by a third (loss of 9% of yield), which is more careful in order to protect the stock and preserve the resource in a sustainable way. References Djabali, F., Mehailia, A, Koudil, M., Brahmi B. (1994). A reassessment of equations for predicting natural mortality in Mediterranean teleosts. Naga, the ICLARM Quarterly 17:1, 33-34. Jones, R. (1984). Assessing the effects of changes in exploitation pattern using length composition data (with notes on VPA and cohort analysis). FAO Fisheries Technical Paper 256. Rome: Food and Agriculture Organization of the United Nations. Thompson, W. F., & Bell, F. H. (1934). Effect of changes in intensity upon total yield and yield per unit of gear. Report of the International Fisheries Commission 8, 7-49. Keywords: Algerian basin, Bottom trawling, Gobiidae, Mediterranean Sea, VBGM Conference: XVI European Congress of Ichthyology, Lausanne, Switzerland, 2 Sep - 6 Sep, 2019. Presentation Type: Oral Topic: ECOLOGY AND LIFE CYCLES Citation: Kassar A, Benallia A, Bouchelif D and Hemida F (2019). Population dynamics and yield of the black goby Gobius niger L. in Algeria (Gulf of Annaba). Front. Mar. Sci. Conference Abstract: XVI European Congress of Ichthyology. doi: 10.3389/conf.fmars.2019.07.00140 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 22 Jul 2019; Published Online: 14 Aug 2019. * Correspondence: Mr. Abderrahmane Kassar, École Nationale Supérieure des Sciences de la Mer et de l'Aménagement du Littoral, Algiers, Algeria, a.w.kassar@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Abderrahmane Kassar Alaeddine Benallia Daoud Bouchelif Farid Hemida Google Abderrahmane Kassar Alaeddine Benallia Daoud Bouchelif Farid Hemida Google Scholar Abderrahmane Kassar Alaeddine Benallia Daoud Bouchelif Farid Hemida PubMed Abderrahmane Kassar Alaeddine Benallia Daoud Bouchelif Farid Hemida Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.