Scientific Research

Yellowfish Working Group

From Waterwheel Magazine

The Water Wheel is a magazine aimed at improving general public understanding of science and technology. The Water Wheel has been in publication since 2002 with material being sourced from outside the WRC.

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Yellowfish movement behaviour

We have all asked ourselves - Do Yellowfish stay in one place, do they move around - how far do they move around upstream and downstream. Findings related to the above questions were recently published in a research paper entilted: "Habitat preferences and movement of adult yellowfishes in the Vaal River, South Africa" by Gordon C. O'Brien from the Water Research Group, Unit for Environmental Sciences and Management, North-West University.

 

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O'Brien GC, Jacobs F, Cronje L, Wepener V, Smit NJ. Habitat preferences and movement of adult yellowfishes in the Vaal River, South Africa. S Afr J Sci. 2013;109(7/8), Art. #0095, 8 pages. http://dx.doi.org/10.1590/ sajs.2013/20120095

 

Abstract: 

The yellowfishes of the Vaal River (Labeobarbus kimberleyensis and L. aeneus) are charismatic, socially and economically important fishes, but very little is known about their interspecies habitat preferences and movement. This study is the first behavioural study of yellowfish in the Vaal River using radio transmitters to characterise habitat preferences and movement patterns. A total of 22 adult L. kimberleyensis and 13 adult L. aeneus individuals were tracked for between 1 month and 1 year from 23 September 2006 to 16 May 2010. Radio telemetry revealed that yellowfish established routine daily behavioural patterns through which the habitat preferences and movement of the species could be established. Home ranges of the yellowfish ranged from 1 km to more than 12 km in the Vaal River depending on the species and habitat availability. Habitat preferences varied between species and included deep slow-flowing habitats with associated cover features particularly in winter for L. kimberleyensis and shallow fast-flowing habitats particularly for L. aeneus in spring, summer and autumn. Changes in flows, habitat availability and atmospheric pressure affected the movement of yellowfish. The biology and ecology of the yellowfish in the Vaal River is noticeably more complicated and dynamic than previously documented. We recommend that the behavioural ecology of these and other yellowfish populations in the Vaal River should continue to be characterised, and the use of the movement of yellowfish be developed as an indicator of ecosystem change.

Full article

The impact of angling on smallmouth and largemouth yellowfish, labeobarbus aeneus and labeobarbus kimberleyensis, in Lake Gariep, South Africa

A large sportfishery that targets both smallmouth (Labeobarbusaeneus) and largemouth (Labeobarbus kimberleyensis ) yellowfish exists in South Africa. Both species have high conservation priority, and no assessments documenting the effect of angling on L.aeneus and L.kimberleyensis have been undertaken. The overall aim of this study was to provide an assessment of the impact of angling on L.aeneus and L.kimberleyensis. The specific objectives of this study were to characterise the sectors utilising Lake Gariep, document catch, effort and total catch for the fishery as well as the locality specific biology of L. aeneus and L. kimberleyensis. The study was undertaken on Lake Gariep, South Africas largest impoundment, situated on the Orange River system in central South Africa
 
 
 
Compiled by: BRUCE ROBERT ELLENDER
Rhodes University
 
Summary
 
This thesis aims to assess the impact of recreational and subsistence angling on L . aeneus and L .kimberleyensis in Lake Gariep by: (1) assessing the biology of L. aeneus and L.kimberleyensis in the lake; (2) documenting catch, effort, size selectivity and total catch for both species from the fishery; and (3) based on the findings, make recommendations for future management of these species.
 
 
 
 
 

Characterisation of the social and economic value of the use and associated conservation of the yellowfishes in the vaal river

As a targeted angling species, the use and related conservation initiatives of the yellowfish in the Vaal River, to facilitate this angling industry, have been poorly characterised and are infrequently considered in the establishment of management actions for this system.
This study aims to characterise the social and economic benefits and implications associated with the use of the Vaal River by yellowfish dependent angling activities and yellowfish related conservation initiatives.

 

compiled by:

Melissa Brand1, Jennifer Maina2, Myles Mander3 and Gordon O’Brien4*

1 Centre for Aquatic Research, University of Johannesburg, P.O. Box 524, Aucklandpark, 2006 This email address is being protected from spambots. You need JavaScript enabled to view it.
2 Sociology Department, University of Johannesburg, P.O. Box 524, Aucklandpark, 2006
3 Future Works, PO Box 2221, Everton, 3625 This email address is being protected from spambots. You need JavaScript enabled to view it.
4 Centre for Aquatic Research, University of Johannesburg, P.O. Box 524, Aucklandpark, 2006, This email address is being protected from spambots. You need JavaScript enabled to view it.

 

SUMMARY

This study aims to characterise the social and economic benefits and implications associated with the use of the Vaal River by yellowfish dependent angling activities and yellowfish related conservation initiatives.
The methods used to achieve the aim of the study include the use of valid economic and social assessment methodologies currently used by local and international ecosystem managers. The economic component of the study was carried out by making use of questionnaire based surveys and personal interviews. The social component of the study involved a comprehensive desktop review of the historical findings of studies addressing fish conservation and recreation and their social benefits. In addition the social component of the study was achieved by undertaking a field survey where various stakeholders of the use and or conservation of yellowfish in the Vaal River ecosystem were interviewed.
The study resulted in 91 questionnaires being comprehensively completed by anglers, an additional 23 equipment retail store representatives were interviewed 17 accommodation sector representatives were interviewed, and numerous interviews were carried out with professional guides, conservationists, specialist consultants and academic researchers as well as with various magazine editors, Vaal River ecosystem managers and municipality representatives.

Following the outcomes of this study recommendations are made to establish an integrated use and associated conservation plan for the yellowfish in the Vaal River and assess risk posed to the continued survival of yellowfish individuals by the so called ecologically friendly practice of catch-and-release of yellowfish.

 

FULL STUDY HERE

 

 

 

 

 

 

Technical report on the state of Yellowfishses in South Africa

The 2007 technical report comprises 11 chapters, with an introduction followed by nine species accounts and a final chapter on invasive alien yellowfishes in South Africa.
Ichthyologists and conservation officials who have a sound knowledge  The report concludes with an appendix containing the most comprehensive list of yellowfish reference material available.

 

Report to the
Water Research Commission by The Yellowfish Working Group
Edited by
ND Impson1, IR Bills2 and L Wolhuter3
1 CapeNature
2 South African Institute of Aquatic Biodiversity
3 Federation of South African Flyfishers

EXECUTIVE SUMMARY
The Executive Committee of South Africa’s national Yellowfish Working Group (YWG)
recommended in 2006 that a status report be compiled for the nine “yellowfishes” that are the focus of the Group’s activities. These species include six true yellowfishes (Labeobarbus spp.) and three large Barbus species (B. andrewi, B. rapax and B. serra) that closely resemble yellowfishes. The Committee further recommended that two reports be produced: a popular report for the layman (e.g. anglers, riparian land-owners) and a technical report, aimed at scientists and conservation staff, that would provide comprehensive and updated information on the status of the nine species. Funding was needed to produce such reports, and the Water Research Commission approved an application, managed by the Federation of Southern African Flyfishers (FOSAF), in 2006. The popular report was released at the annual conference of the YWG in April 2007.

 

Full Report

 

 

 

 

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