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River connectivity and fish migration considerations in the management of multiple stressors in South Africa

Gordon C. O’Brien https://orcid.org/0000-0001-6273-1288 A F , Mathew Ross B , Céline Hanzen https://orcid.org/0000-0001-6278-0258 C , Vuyisile Dlamini https://orcid.org/0000-0003-1462-1775 A , Robin Petersen D , Gerhard J. Diedericks E and Matthew J. Burnett https://orcid.org/0000-0002-6237-1697 C
+ Author Affiliations
- Author Affiliations

A University of Mpumalanga, School of Biology and Environmental Sciences, Faculty of Agriculture and Natural Sciences, Private Bag X11283, Nelspruit, 1200, South Africa. Email: vuyisile.dlamini@ump.ac.za

B EnviRoss CC, PO Box 369, Wendywood, 2144, South Africa. Email: mathew@enviross.co.za

C University of KwaZulu–Natal, School of Life Sciences, Private Bag X01, Scottsville, Pietermaritzburg, 3201, South Africa. Email: celine@riversoflife.co.za; matthewburnett014@gmail.com

D Scientific Services, South African National Parks, Skukuza, Kruger National Park, 1350, South Africa. Email: robin.petersen@sanparks.org

E Environmental Biomonitoring Services, Postnet Suite 225, Private Bag X9910, White River, South Africa. Email: gerhardd@mweb.co.za

F Corresponding author. Email: gordon.obrien@ump.ac.za

Marine and Freshwater Research 70(9) 1254-1264 https://doi.org/10.1071/MF19183
Submitted: 18 May 2019  Accepted: 1 July 2019   Published: 16 July 2019

Abstract

People throughout the world depend on the services we derive from freshwater ecosystems. Human land-use activities often affect the quality, quantity and habitat of freshwater ecosystem, which need to be carefully managed to ensure their integrity and provision of services is sustainable. In South Africa, legislation has established resource-directed measures to attain a sustainable balance between the use and protection of water resources. These procedures have been implemented in most of South Africa’s nine water-management areas, resulting in new legislation to protect these resources. Unfortunately, very little protection has been afforded to river connectivity maintenance and fish migrations. For water storage and flow regulation for agriculture and other resource use activities, >610 formal dams and ~1430 gauging weirs have been constructed that act a partial or complete barriers to fish migration on river ecosystems. Only ~60 fish passage structures have been built, but many are not functional. River connectivity and fish migration management appears to be a shortcoming of the existing management approach for multiple stressors.

Additional keywords: fish passage, resource protection, resource use, sustainability, water resources management.


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