KAMPALA. Egypt has offered to research on the control and elimination of giant salvinia molesta, a new water weed, described by experts as worse than the water hyacinth. According Minister of Agriculture, Animal Industry and Fisheries, Mr. Tress Bucyanayandi, the fast growing aquatic, which has massively spread on Lake Albert and Lake Kyoga are characterised by forming dense mats, brown, yellow or green in colour that affect fish and fisher men.
“Egypt has promised to pick samples of the weed and research more on it. This is a commendable move and I take this opportunity to applaud the Egyptian government. This weed is more complicated than the water hyacinth because it reduces oxygen to fish, makes it difficult to fish and our machines to harvest it because it is smaller,” he said.
Speaking after meeting Egypt Minister of Water Resources and Irrigation Prof. Hossam Moghazy, at his office in Entebbe at the weekend, Buchanayandi said the new weed possess big threat to our fish sector.
Uganda earned US$136.2 million as of December 14, 2015 from fish exports while coffee fetched US$466.6 million) and tea (US$72.1 million). Prof. Hossam Moghazy who was in Uganda for a three day visit said he is to dispatch an Egyptian technical research team to Uganda in January to embark on the investigation.
During his stay, Moghazy announced a grant of US$4.5 million (about Shs15billion) to control Kasese floods.
The weed referred to by locals as Nankabirwa, due to the absence of a native name is ranked by the International Conservation Union (IUCN) among the worst 100 invasive weeds in the world.
The importation of Salvinia has been outlawed in many developed countries because of its devastating ecological and economic effect. The weed was added to the European and Mediterranean Plant Protection Organization (EPPO) Alert List in 2007 and transferred to the List of Invasive Alien Plants in 2012 (EPPO 2012), according to IUCN.
Research indicates that this aquatic fern, thrives in slow-moving, nutrient rich, warm, freshwater. It grows very rapidly, out-competing most aquatic plants and is dispersed long distances within water bodies via water currents and between water bodies through animals and contaminated equipment, boats or vehicles.
Wikipedia further states that within a week under right circumstances, the weed, due to its rapid multiplication rate, can double in volume thereby clogging water ways and covering up the entire surface of the lake.
It states that the weed can inhabit many water environments including streams, rivers, ponds, aquariums, wetlands as well as rice fields
“The stealthy invader is very problematic to humans and the ecosystem due to its thick mats on water thus, hindering activities like agricultural irrigation, water transport, fishing and power generation. It can also deplete the oxygen source in water and block sunlight needed by aquatic organisms like fish and insects, among others,” It reads. Adding, “It also acts as a haven for mosquitoes, snakes, crocodiles and others which are a threat to human health and physical wellbeing.”
It further explains that the weed is known to be spread by boaters from site to site since it hitch-hikes on boats.
“The young and even just small fragments of the weed may travel naturally in moving water and establish colonies wherever they settle. In other cases, the weed might be recklessly dumped in water by humans out of ignorance; unaware of the consequences of their actions.”
Wikipedia further states that biological control with a weevil named Cyrtobagous salviniae is possible.
“This weevil, which can be obtained from the Agricultural Research Service in the United States Department of Agriculture, is well known for reducing and completely checking Giant Salvania weed.
It has been used in several countries like Austria, Zimbabwe, New Zealand, Zambia, New Guniea and others attaining great success. Also using Salvinia grasshopper, water lettuce moth and others can be effective since they also control other invasive water weeds including water hyacinth,” it further explains.