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Protect our Fish

13.11.12

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The fish population of the Vaal River live within certain environmental conditions. Changes within this environment may result in fish kills, a world-wide phenomenon that occur due to natural or man-induced factors.

We would like to protect the aquatic integrity of the Vaal River and maintain the current species composition (typical fish species found in the Vaal River are illustrated on this poster). 

Your assistance is needed to timeously report any incidents within the Vaal River and Vaal Barrage that may result in fish kills. This poster provides contact details, information requirements, and fish illustrations that will assist you in reporting such incidents.
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Natural causes:

  • Old age
  • Oxygen depletion
  • Oxygen supersaturation
  • Toxic algal blooms
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  •  Turnover of the water column
  • Sudden temprature changes
  • Salinity changes
  • Bacterial infections
  • Parasites
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 Man-induced factors:

  • Discharge of pesticides, fertilisers, or industrial effluent into the water which can kill fish.
  • Discharge of raw sewage into the water resource.
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 Please contact the following organisations if you discover a fish kill:
Department of Water Affairs and Forestry: Gauteng Regional Office: (012) 392 1300
Hotline (Leeu/Taai Forum): 0800 204 920
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 Picture11  If possible record the following information to assist in identifying the cause of the fish kill:  Picture12
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  •  Date and time
  • Location
  • Weather
  • Extent of fish kill
  • Presence of Algal blooms
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  •  Water flow
  • Sources of pollution
  • Excessive aquatic plant growth
  • Species of fish
  • Fish behaviour
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 DWA logo  RW logo  Sasol logo
Fish illustrations with permission from, and copyright to the South African Institute for Aquatic Biodiversity. Illustrations are from the book by SKELTON, P.H. (1993), A COMPLETE GUIDE TO THE FRESHWATER FISHES FO SOUTHERN AFRICA. Southern Book Publishers (Pty) Ltd