On the Yucatecan coast of Sisal, a laboratory at the National Autonomous University of Mexico (UNAM) has become a bridge between scientific knowledge and the experience of those who live and work in the sea. There, local fishermen are integrated into sustainable aquaculture projects, building, together with specialists, a collaborative model that respects the ecosystem and promotes new forms of production.
Manuel Valenzuela, an academic at the Faculty of Science and in charge of the laboratory, explained that the space not only generates knowledge about the coastal area of Yucatán, but also allows us to experiment and promote sustainable aquaculture practices. Its greatest value lies in opening its doors to local fishermen.
They currently cultivate mostly shrimp. Source: Itzel Chan.
“Traditional aquaculture requires a lot of investment, infrastructure and resources; here we have realized that it is necessary to rethink that logic. For example, avoid monocultures. There are those who only grow shrimp, but we have seen that you can work with the entire food chain,” said Valenzuela.
Located within the UNAM campus in the town of Sisal, a few meters from the sea and separated only by a strip of dunes, the laboratory houses ponds of different sizes, ranging from one liter to 120 liters, in which shrimp are grown using the biofloc technique.
This system reduces water consumption, eliminates the need for chemicals and generates microorganisms that serve as food for smooth fish introduced into the same environment. Added to this are macroalgae that, by absorbing nitrogen and phosphorus, contribute to the natural filtration of water.
In these ponds there are smooth fish, shrimp and seaweed, arranged in due process. Source: Itzel Chan.
“After passing through the algae, the water is almost clean, but it still contains some nitrogen. Who is interested in that waste? To halophytic plants, which tolerate high concentrations of salt. This completes the cycle and the final filter,” said the academic.
This approach allows the development of sustainable technologies that not only care for the environment, but are economically viable. However, Valenzuela warns that the momentum for aquaculture has declined.
A decade ago there were 450 farms in Yucatán; today, there are only 30 left. He attributes this decline both to the lack of institutional interest and to the disinterest of society, especially since government authorities do not bet on training and when working with sustainability, it is costly for people to sustain aquaculture.
“People are already beginning to understand that fishing is not inexhaustible. But it's not enough to tell them to do aquaculture, we have to teach them how to do it without harming the environment or the animals,” he stressed.
Macroalgae absorb nitrogen and phosphorus that is produced in ponds. Source: Itzel Chan.
With that mission, the laboratory remains open all year round. Fridays receive visits from students —from preschool to university level— and, above all, from fishermen from municipalities such as Celestún and Telchac Puerto.
One of them is José Ricardo Novelo Chac, a fisherman and defender of the fishing shelter in Celestún. For him, visiting the laboratory has been an enriching experience.
“It is very valuable that scientists explain their work to us and that we too can contribute from our practice. We learn from each other,” he said.
Every time he returns home, he does so with the idea that in the future, seeding will be necessary.
“In this space they give us the scientific part and we have the experience in the field. I know that we have been working in fishing for many years, but we are running out of fish, so maybe mariculture is what's next right now,” he reflected.
This is a type of halophyte plant that filters water in ponds where shrimp are located. Source: Itzel Chan.
From his experience, he confirms that the problems faced by fisheries are not reduced to overfishing, but that they include threats such as climate change. Therefore, he concludes, it is time to prepare new generations for a different way of inhabiting and cultivating the sea.
“It's about overfishing, but it's also about threats such as climate change. Maybe it's time to teach our future generations how to sow in the sea through aquaculture and mariculture,” he said.
* This article was written by Itzel Chan, who covers coastal communities thanks to the support of the Report for the World program .
Comentarios (0)