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Dr Julie Coetzee

Discipline: Entomology, Biological Control

Julie Coetzee

Office: Biological Sci Bldg, Lab 110

Phone: +27 46 603 8702

Email: julie.coetzee@ru.ac.za


PhD 2003 University of the Witwatersrand






Julie completed her PhD at the University of the Witswatersrand in 2003. Currently her research focuses on the biological control of invasive aquatic plants. She started working on biological control agents of water hyacinth in 1998, and has never looked back. Recently she has shifted the focus of her work on floating aquatic plants to submerged aquatic plants. As we have gained excellent control of the floating species, the submerged species have taken advantage of these new habitats, threatening indigenous aquatic flora and fauna. Working on submerged plants is a lot more challenging than on floating plants as we have to find insects that complete their life cycle underwater. This work is allowing us to explore new countries in an attempt to find the best agents for the plants.


Research Interests

  • Biological control of weeds

  • Plant-insect interactions

  • Invasion biology

  • Insect physiology

  • Thermal ecology

  • Aquatic plant ecology
  • Species distribution modelling

  • Biostatistics


Recent Publications

  • Owen, C. A., Coetzee, J. A. and van Noort, S. 2015. Distributional range of the South African maritime spider-egg parasitoid wasp, Echthrodesis lamorali (Hymenoptera: Platygastridae: Scelioninae). African Invertebrates 55: 323-332.

  • Burke, A, Coetzee, J.A. and Hill, M.P. 2014. Effect of nutrient quality and leaf age of water hyacinth, Eichhornia crassipes, on the development of its co-evolved herbivore, Eccritotarsus catarinensis (Hemiptera: Miridae). African Entomology 22: 896-899.

  • Weyl, P.S.R. and Coetzee, J.A. 2014. The invasion status of Myriophyllum spicatum L. in southern Africa. Management of Aquatic Invasions 5: 31-37.

  • Coetzee, J.A., Jones, R.W. and Hill, M.P. 2014. Water hyacinth, Eichhornia crassipes Pontederiaceae), reduces benthic macroinvertebrate diversity in a protected subtropical lake in South Africa. Biodiversity and Conservation 23: 1319–1330.

  • Canavan, K., Coetzee, J.A., Hill, M.P. and Paterson, I.P. 2014. The effect of water eutrophication on the impact of the water hyacinth moth, Niphograpta albigutallis Warren (Lepidoptera: Crambidae), on Eichhornia crassipes (Mart.) Solms-Laub. (Pontederiaceae). African Journal of Aquatic Science 39: 203-208.

  • Martin, G.D. and Coetzee, J.A. 2014. Competition between two aquatic macrophytes, Lagarosiphon major (Ridley) Moss (Hydrocharitaceae) and Myriophyllum spicatum Linnaeus (Haloragaceae) as influenced by substrate sediment and nutrients. Aquatic Botany 114: 1-11.

  • Madeira, P.T., Center, T.D., Coetzee, J.A., Pemberton, R.W., Purcell, M.F. and Hill, M.P. 2013. Identity and origins of introduced and native Azolla species in Florida. Aquatic Botany 111: 9-15.  

  • Weyl, P. and Coetzee, J. 2014. An integrated remote sampling approach for aquatic invertebrates associated with submerged macrophytes. African Journal of Aquatic Science 38: 337-340.

  • May, B. and Coetzee, J.A. 2013. Comparisons of the thermal physiology of water hyacinth biological control agents: predicting establishment and distribution pre- and post-release. Entomologia Experimentalis et Applicata 147: 241-250.

  • Martin, G.D., Coetzee, J.A. and Baars, J-R. 2013. Hydrellia lagarosiphon Deeming (Diptera: Ephydridae), a potential biological control agent for the submerged aquatic weed, Lagarosiphon major (Ridl.) Moss ex Wager (Hydrocharitaceae). African Entomology 21: 151-160.

  • Hill, M.P., Coetzee, J.A. and Ueckermann, C. 2012.  The acute toxic effect of herbicides used in water hyacinth control on two insect species released for its biological control in South Africa.  Biocontrol Science and Technology 22: 1321-1333.

  • Coetzee, J.A. and Hill, M.P. 2012. The role of eutrophication in the biological control of water hyacinth, Eichhornia crassipes, in South Africa. BioControl 57:247–261.

  • Coetzee, J.A. 2012. Meteorological weather station data can be used in climate matching studies of biological control agents. Biocontrol Science and Technology 22: 419-427.

  • Robertson, M.P., Harris, K.R., Coetzee, J.A., Foxcroft, L.C., Dippenaar-Schoeman, A.S. and van Rensburg, B.J. 2011. Assessing local scale impacts of Opuntia stricta (Cactaceae) invasion on beetle and spider diversity in Kruger National Park, South Africa. African Zoology 46: 205–223.

  • Albano Pérez, E., Coetzee J.A., Ruiz Téllez T. and Hill M.P. 2011. Water hyacinth (Eichhornia crassipes) seed bank dynamics in South Africa: the regeneration potential of the infestation. South African Journal of Botany 77: 795–800.

  • Paterson, I.D., Coetzee, J.A., Hill, M.P. and Downie, D.A. 2011. A pre-release assessment of the relationship between the invasive alien plant, Pereskia aculeata Miller (Cactaceae), and native plant biodiversity in South Africa. Biological Control 57: 59-65.

  • Martin, G.D. and Coetzee, J.A. 2011. Fresh water aquatic plant invasion risks posed by the aquarium trade, aquarists and the internet trade in South Africa. WaterSA 37: 371-380.

  • Coetzee, J.A., Bownes, A. and Martin, G.D. 2011. Prospects for the biological control of submerged aquatic macrophytes. African Entomology 19: 469–487.

  • Coetzee, J.A., Hill, M.P., Byrne, M.J. and Bownes, A.B. 2011. A review of the biological control programmes on Eichhornia crassipes (C. Mart.) Solms (Pontederiacaeae), Salvinia molesta D.S. Mitch. (Salviniaceae), Pistia stratiotes L. (Araceae), Myriophyllum aquaticum (Vell.) Verdc. (Haloragaceae) and Azolla filiculoides Lam. (Azollaceae) in South Africa since 1999. African Entomology 19: 451–468.

  • Hill, M.P., Coetzee, J.A., Julien, M. and Center, T.D. 2011. Water hyacinth. In: Simberloff, D. and Rejmanek, M. (eds). Encyclopedia of Biological Invasions. University of California Press, Berkeley. Pp. 689-692.

  • Van Driesche, R.G., R.I. Carruthers, T. Center, M.S. Hoddle, J. Hough- Goldstein, L. Morin, L. Smith, D.L. Wagner, B. Blossey, V. Brancatini, R. Casagrande, C.E. Causton, J.A. Coetzee, J. Cuda, J. Ding, S.V. Fowler, J.H. Frank, R. Fuester, J. Goolsby, M. Grodowitz, T.A. Heard, M.P. Hill, J.H. Hoffmann, J. Huber, M. Julien, M.T.K. Kairo, M. Kenis, P. Mason, J. Medal, R. Messing, R. Miller, A. Moore, P. Neuenschwander, R. Newman, H. Norambuena, W.A. Palmer, R. Pemberton, A. Perez Panduro, P.D. Pratt, M. Rayamajhi, S. Salom, D. Sands, S. Schooler, A. Sheppard, R. Shaw, M. Schwarzländer, P.W. Tipping, R.D. van Klinken. 2010. Classical biological control for the protection of natural ecosystems. Biological Control Supplement 1: 2-33.

  • Baars, J-R., Coetzee, J.A., Martin, G.D., Hill, M.P. and Caffrey, J.M. 2010. Natural enemies from South Africa for biological control of Lagarosiphon major (Ridl.) Moss ex Wager (Hydrocharitaceae) in Europe. Hydrobiologia 656:149–158.

  • Diop, O., Coetzee, J.A. and Hill, M.P. 2010. Impact of different densities of Neohydronomus affinis Hustache (Coleoptera: Cuculionidae) on Pistia stratiotes Linnaeus (Araceae) under laboratory conditions. African Journal of Aquatic Science 35: 267–271.

  • Coetzee, J.A., Byrne. M.J., Hill, M.P. & Center, T.D. 2009. Should the mirid, Eccritotarsus catarinensis (Heteroptera: Miridae), be considered for release against water hyacinth in the United States of America? Biocontrol Science and Technology 19: 103-111.

  • Coetzee, J.A., Hill, M.P. and Schlange, D. 2009. Potential spread of the invasive plant Hydrilla verticillata in South Africa based on anthropogenic spread and climate suitability. Biological Invasions 11: 801–812.

  • Coetzee, J.A. and Hill, M.P. 2009.  Management of Invasive Aquatic Plants.  In: Clout, M.N. & Williams, P.A. (eds) Invasive Species Management. A Handbook of Techniques (Techniques in Ecology and Conservation). Oxford University Press, London, pp. 141-152.

  • Coetzee, J.A., Hill, M.P., Julien, M.H., Center, T.D. and Cordo, H.A. 2009.11.Eichhornia crassipes.  In: Muniappan, R., Reddy, G.V.P., Raman, A. and Gandhi, V.P. (eds) Biological control of tropical weeds using arthropods. Cambridge University Press, Cambridge, UK. Pp. 181-208.

  • Coetzee, J.A. and Hill, M.P. 2008. Biological control of water hyacinth (Eichhornia crassipes) – the South African experience. EPPO Bulletin/ Bulletin OEPP, 38: 458–463.

  • Coetzee, J.A. and Hill, M.P. 2008. EPPO data sheet on Invasive Plants: Eichhornia crassipes. EPPO Bulletin/ Bulletin OEPP, 38: 441-449.

  • Hill, M.P. and Coetzee, J.A. 2008. Integrated control of water hyacinth (Eichhornia crassipes) in Africa. EPPO Bulletin/ Bulletin OEPP, 38:452-457.

  • Morris, T.L., Witkowski, E.T.F. and Coetzee J.A. 2008. Initial response of riparian plant community structure to clearing of invasive alien plants in Kruger National Park, South Africa. South African Journal of Botany 74: 485-494.

Last Modified :Thu, 27 Apr 2017 16:25:48 SAST