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Published yearly: 

4 Issues

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ISSN: 2320-964X (Online) 

ISSN: 2320-7817  (Print)

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Dr. Santosh Pawar 


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ORIGINAL ARTICLE

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Int. Journal of Life Sciences, 2017; 5(2): 180- 188    |    Available online, June 30, 2017

The community structure of demersal fish species from bottom-trawls off Namibia and the West coast of South Africa


Mafwila SK

 

 

Sam Nujoma Marine and Coastal Resources Research Centre, and Department of Fisheries and Aquatic Sciences, P.O. Box 462 Henties Bay, Namibia. E-mail: smafwila@unam.na

 

Received: 15.02.2017    |     Accepted: 24.06.2017    |      Published :30.06.2017

Changes in the structure and composition of the demersal fish assemblages are assessed using a variety of ecosystem indicators known to capture such changes, which may be induced by bottom-trawling. The aim of this study was to investigate whether there are any structural changes in demersal fish assemblages by way of latitudinal variation. The study was conducted from the Kunene River to Agulhas Bank during the 2007 demersal surveys. Abundance and biomass data was analysed using cluster analysis, non-metric multidimensional scaling, abundance biomass comparison curves, and similarity profiles in PRIMER v6 software. The dendrogram identified three main groups, two in northern Benguela, separated into shelf and slope assemblages and one in the southern Benguela, without any distinction between shelf and slope at 19% similarity.  Identified assemblages are spatially distinct. The average similarities on the continental shelf in northern Benguela were driven by the following top three species: M. capensis, Sufflogobius bibarbatus and Trachurus trachurus capensis; on the continental slope they were driven by M. paradoxus, Nezumia micronychodon and Helicolenus dactylopterus; while the similarities in southern Benguela assemblages were driven by M. paradoxus, H. dactylopterus and Lophius vomerinus, in order of % contribution.

 

Keywords: Demersal fish, bottom-trawling, community structure, assemblages


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Editor: Dr. Arvind Chavhan

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Cite this article as:

Mafwila SK (2017) The community structure of demersal fish species from bottom-trawls off Namibia and the West coast of South Africa International J. of Life Sciences, 5  (2): 180-188.

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Conflicts of interest: The authors stated that no conflicts of interest.

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Copyright: © 2017 | Author(s), This is an open access article under the terms of the Creative Commons Attribution-Non-Commercial - No Derivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

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