This week a strong measure was carried out in San Vicente, Buenos Aires province, to combat the water hyacinth plague that invades the lagoon.
Insects were released that feed specifically to “release” the water mirror.
This Tuesday, scientists from CONICET and the Foundation for the Study of Invasive Species (FUEDEI) together with students from Agricultural School No. 1 carried out the activity of “biological control”.
Water hyacinth plague in the San Vicente lagoon: the measure to combat it
Although the water hyacinth is native to Argentina, it is not native to the ecoregion where the San Vicente lagoon is located.
For this reason, the invasive species can have negative consequences on the ecosystem. “We carried out the first release of megamelus scutellaris, this insect from the La Plata River Basin, where the water hyacinth is originally from,” detailed Dr. Alejandro Sosa, researcher at FUEDEI and CONICET.
“It was raised in pools at the Agricultural School, with the participation of the kids. They themselves raised them, collected them and released them into the lagoon,” he added in a dialogue with the local newspaper El Diario Sur.
“It is a little leafhopper that has a mouthpart that pierces and sucks the sap from the water hyacinth. The idea is for the insect population to grow rapidly so that the plant population collapses,” he emphasized.
“We plan to make several introductions during the year, something massive, to carry out an augmentative biological control,” added Sosa.
These are different insects from the weevils that had been introduced into the lagoon as part of a similar project in 2018. According to specialists, this technique has already proven its effectiveness in different environments around the world, especially in an urban lake in South Africa.
They also clarified that the water hyacinth will not disappear completely, but the plague will be controlled.
The team of researchers participating in the new biological control project includes: Alejandro Sosa, Ana Faltlhauser, Delfina Contestabile, and the Fulbright program fellow Alexander Cho, who came as part of an exchange from Texas, United States.
The initiative is carried out with the support of Agricultural School 1, the District Education Office of San Vicente, and the Municipality.
Cleaning of the water mirror
In parallel with the biological control strategy, this Monday the Municipality of San Vicente announced the incorporation of new machinery for cleaning the lagoon.
It is a boat equipped with blades at the front to cut the plants, load them onto a shovel, and then remove them to the shore.
This is the second equipment of this type put into operation. CONICET scientists believe that, with the action of the insects, the water hyacinths will see their size reduced, facilitating the mechanical removal work.
