Oral Presentation International Conference on River Connectivity (Fish Passage 2018)

Understanding the effects of flow on the movement of Yellowfish using the FISHTRAC programme as a management tool in Southern Africa: Crocodile River, Kruger National Park case study. (#114)

Matthew J Burnett 1 , Gordon C O'Brien 1 , Graham Jewitt 1
  1. University of KwaZulu-Natal, Pietermaritzburg, KWAZULU-NATAL, South Africa

The excessive use of aquatic ecosystem services in developing countries has caused a decline in ecosystem integrity processes. Alterations to flow, habitat and water quality from dams, abstractions and users are among the main drivers towards the decline in ecosystem integrity and processes. The FISHTRAC programme has been established to promote the development of, and use of fish movement variables in the evaluation of ecological consequences for altered flow, habitat and water quality in southern Africa. Numerous evidence research studies have been undertaken on the Vaal (O’brien et al. 2013, Jacobs et al. 2016, Ramesh et al. 2017) and Crocodile Rivers (Burnett et al. 2018) to evaluate the behavioural ecology, home range, daily and seasonal migratory behaviour and movement responses to changes in environmental variable. The most recent Crocodile River evidence-based research has shown the response of yellowfish towards the releases of flows from upstream. Understanding these responses can assist park and water affairs managers to reach the required environmental flows both within and outside the Kruger National Park. This behavioural study included the use of manual and remote fish tracking techniques developed for the FISHTRAC programme with a range of flow, water quality and habitat evaluation methods. Established univariate and multivariate statistical and probability modelling techniques were used to evaluate the response of fish behavioural data (+180 00 data strings) to the changes in environmental variable states. The movement responses by yellowfish resulted in the establishment of a four primary levels of fish movement response this includes the disruption of established behaviour, significant reduction in movement, prolonged residency of refuge areas and vacation of their core home range. These responses can be incorporated into water resource management in South Africa, and used to monitor the wellbeing of the variable states in real time and remotely using the FISHTRAC approach.

  1. O'Brien, G.C., Jacobs, F., Cronje, L., Wepener, V. and Smit, N.J., 2013. Habitat preferences and movement of adult yellowfishes in the Vaal River, South Africa. South African Journal of Science, 109(7-8), pp.01-08.
  2. Jacobs, F.J., O'Brien, G.C. and Smit, N.J., 2016. Diel movement of smallmouth yellowfish Labeobarbus aeneus in the Vaal River, South Africa. African Journal of Aquatic Science, 41(1), pp.73-76.
  3. Ramesh, T., Downs, C.T. and O’Brien, G.C., Movement response of Orange-Vaal largemouth yellowfish (Labeobarbus kimberleyensis) to water quality and habitat features in the Vaal River, South Africa. Environmental Biology of Fishes, pp.1-13.
  4. Burnett, M.J. O'Brien, G.C. Wepener, V. Pienaar, D. 2018. The spatial ecology of adult Labeobarbus marequensis and their response to flow and habitat variability in the Crocodile River, Kruger National Park. South African Journal of Aquatic Science, (In Press).
  5. O’Brien GC, Jacobs FJ, Burnett MJ. Kruger P, Botha IF, Cordier JA. 2013a. Remote and manual radio telemetry methods to monitor and use fish behaviour in South Africa’s inland waters. Report No. 2111/1/13. Pretoria: ISBN: Water Research Commission, Pretoria.