Aquatic weed survey 2013

Aquatic weed survey 2013
Grant D. Martin and Matthew C. Parkinson
Department of Zoology and Entomology, Rhodes University, Grahamstown, 6140, South Africa. ,

Annually,   the   Rhodes   University   Entomology   Department,   funded   by   Working   for   Water, Department of Water Affairs, conducts a national aquatic weed survey. To date in 2013 over 150 aquatic weed sites have been assessed in the Eastern Cape, Western Cape, KwaZulu-Natal, Free State, Gauteng and North West provinces.  High numbers of biological control agents were found at the majority of water hyacinth, water lettuce, salvinia, parrot’s feather and red water fern sites. Excellent control was noted at the majority of sites, however, a couple of sites were found to have no biological control agents particularly in the Eastern Cape. Sagittaria platyphylla, an emerging aquatic invasive, was recorded at sites in the Eastern Cape, KwaZulu-Natal and Western Cape and was found to be spreading within the systems where it has established. A summary of the biological control agents released from the Rhodes University mass rearing facility between May 2012 and May 2013 are also presented.