Salvinia, Salvinia molesta
in south-eastern Brazil, salvinia (Salvinia molesta) was
a serious aquatic weed in Australia, Southeast Asia, the Pacific
and south, central and eastern Africa. It grows quickly to form
thick mats covering lakes, slow-moving rivers and other waterways.
These mats severely interfere with the use of water bodies for boating,
irrigation, flood mitigation and conservation of wildlife.
It took only
one species of small weevil, Cyrtobagous salviniae, to clear
massive infestations of Salvinia in areas like the Sepik River (Papua
New Guinea), Wappa Dam and Lake Moondara (Queensland) and lagoons
in Kakadu National Park (Northern Territory, Australia). Cyrtobagous
was found by CSIRO Entomology scientists in Brazil - the home of
In Sri Lanka,
the benefit to cost ratio of using the biocontrol agent, measured
in hours worked, has been estimated at 1675:1 and in rupees, dollars
or any other currency 53:1.
been controlled in at least 13 other tropical countries as a direct
flow-on from this research.
Lake Moondara before biocontrol
Lake Moondara after biocontrol