Specialists from a department of the Faculty of Agronomy at the University of Buenos Aires (FAUBA) are working on an innovative project to combat dengue.
The project is based on eliminating mosquito larvae that transmit this virus and other diseases. It would be a “more sustainable and economical” prevention measure for water reservoirs in institutions, orchards, gated communities, or buildings.
The project against dengue
It is a project involving two species of native fish, better known as “water mummies,” “little pot-bellied fish,” “junqueritos,” or “tosqueritos.”
They are planted in unused swimming pools or out of season, domestic ponds, water reservoirs in vertical gardens, rainwater collection tanks for irrigation in orchards, or ornamental fountains in buildings.
As the specialists told the newspaper La Nación, the project has already benefited around 300,000 people.
“We are certain that in the water reservoir where we place these fish, no larvae survive. This has been confirmed,” said Alejandro López, a faculty lecturer and project coordinator, along with MarÃa Boveri, head of the Aquaculture department.
How it works
The researchers pointed out that the mosquito larvae Aedes aegypti hatch with the first heat of the year, starting in September with the arrival of spring.
This cycle extends until December, so they emphasized the importance of taking action during these periods throughout the year.
Moreover, considering that in recent years the dengue mosquito has expanded its range further south, and most cases are autochthonous each season.
“It is an efficient and more natural solution for mosquito proliferation because it avoids the use of insecticides and other more costly measures,” said the coordinator.
“The effectiveness of seeding these fish is 100%, and the fact that they are native species is also significant as it helps preserve the ecosystem. They dominate the environment because they are native, and there is no risk of them becoming a plague,” detailed.
How do these fish act against mosquitoes?
Two species are dedicated to this project: Jenynsia lineata and Cnesterodon decemmaculatus.
Regarding mosquito larvae, it eliminates them in all their developmental stages: egg (when they are covered by water where they were attached), larva, and pupa. “It is a specialized predator. It identifies food, recognizes stimuli, and hunts,” explained the researcher.
Due to their size, ranging from a few millimeters to between 3 and 10 centimeters in adulthood, it is recommended to use water mummies in reservoirs of 20 liters or more, if conditions are appropriate.
If the reservoir or planted space is seasonal, such as a pool, the fish can be removed and kept in a fish tank or returned to the faculty, as they have already received specimens from the last winter seasons.
How to request the fish
When they started delivering water mummies free of charge, initially to schools, inquiries and requests became more massive. Clubs, civil and neighborhood associations, architects, municipalities, hospitals, schools, gated communities, and individuals with fountains, ornamental containers, or Australian tanks.
The project officially started in 2022 and has been delivering native fish throughout the year since then, except in January.
It operates on demand and is free of charge: you have to request them by email at [email protected] or through their Instagram account.
Once the request is received, the team sends a form with a few questions, images, and necessary information. Then, they coordinate the day and time of delivery, usually at the faculty.
