COP16: The black soldier fly, an example of how insects are key in the fight against waste

"We humans are guests on a planet of insects. This phrase, coined by Dutch entomologist Marcel Dicke, aptly describes a world in which these tiny organisms, of which more than a million species have been described, control and maintain the delicate dynamics that allow life to fulfill its cycles within ecosystems.

They pollinate so that plants can reproduce, serve as food for some wild animals, provide biological control to prevent some populations from growing to the point of becoming pests, and are even responsible for returning energy to the earth and decomposing our bodies when the life of the beings that walk this planet is over.  

Many of them also have the task of simplifying all kinds of waste so that they can continue their cycle and maintain the balance. This is the job of the black soldier fly. Native to tropical America, it has captured the interest of hundreds of researchers around the world in recent decades for its ability to break down organic matter and convert it into valuable nutrients. It does this simply by feeding on organic waste, such as that from agricultural activities, in a process known as bioconversion. 

"Some species of insects, like the larvae of the black soldier fly, can take advantage of this decomposing waste that would have no use other than being composted and causing other kinds of changes in the environment. What they do is they eat it. What they do is they eat it, and in doing so they reabsorb all those nutrients that would have been lost before, which would generate contamination in the environment through nitrification processes that are very polluting," explains Professor Karol Barragán, a veterinarian at the Universidad Nacional de Colombia (Unal).

In its larval form, the insect - so named for its resemblance to the black uniforms with white belts worn by British soldiers in the 1960s - converts this food source into a protein content that ranges between 38 and 46 percent, making it a valuable source of nutrients, including a significant amount of healthy fats, vitamins and essential minerals, and a great source of food for animals such as fish, birds and pigs, and even for humans. 

Professor Barragán spent five years studying this small animal during her doctoral studies at Wageningen University in the Netherlands. When she returned to the country, she knew that she had to take advantage of the potential of this fly, which is widely used in countries such as China and India for the development of food products, as well as promote the use of other insects that inhabit Colombian territory, which is recognized for its biodiversity.

This research idea, which materialized in the Wildlife Conservation and Management Group of the Terrestrial Arthropod Research Center (Cinat), soon became an initiative called Insects for Peace, which sought to promote the production of the fly to use its larvae as animal feed in rural communities and in the Territorial Spaces for Training and Reincorporation (ETCR), created after the g of the peace agreement with the former FARC to temporarily house its ex-militants. 

"We wanted to give them the opportunity to learn how to use insects to reduce production costs, in addition to being less dependent on external inputs that are extremely expensive, such as commercial feed and fertilizers," explains Professor Barrangán, who explains that this work began at the ETCR Antonio Nariño (Tolima), She explains that this work began at the ETCR Antonio Nariño (Tolima), where the flies reared were used as feed for tilapia, and was later extended to the ETCR Jaime Pardo Leal (Guaviare), as well as to associations of women heads of households and indigenous women, who learned about these processes and expressed interest in participating.

What began as a study idea later became one of the first spin-off companies ed by the National University of Colombia. The company, called Entopro, now advises large waste producers in the country on how to set up systems to use this biomass, which is based on black soldier flies.

"There is too much waste, and there is a great need for protein to feed animals, as well as organic fertilizer. What we are doing is showing that this waste, which is thrown away every day and which companies pay to throw away, can be returned in two products: both flour for animal feed and organic fertilizer for crops, and this resonates with everyone," explains Javier Vázquez, CEO of Entopro.

Vázquez also speaks of fertilizers, because researchers have discovered that the fly's growth process leaves behind residues of excrement, undigested food and exoskeletons, a mixture known as frass, which can act as a substance to improve soil characteristics and even promote the arrival of pollinators to plants and repel pests, as studies by Cinat researchers have shown.

Nothing is lost for the flies. Experts have also found that their exoskeletons - the kind of shells insects shed as they grow - contain high levels of chitin, a polymer that is used as a fiber, an immunostimulant and has antimicrobial properties.

"Among the companies that us the most are, on the one hand, those that produce animal feed, because they have already realized that insect meal can have a very great potential, and on the other hand, those that produce food or snacks, which generate large quantities of organic waste every year and have to pay to get rid of it," says Professor Barragán about the main clients that Entopro has today, a company that currently provides basic employment for six people.

We are currently working exclusively with the black soldier fly, but the idea is to expand to other insects soon," says the professor, who adds that in the field they have been able to identify other native species, such as the yellow soldier fly, the green soldier fly or the blue soldier fly, which could have the same or greater potential for developing these bioconversion processes. 

"Biodiversity is full of ecosystem services, let's identify them, let's quantify them, both to conserve them and to use them in a sustainable way. That's what we're doing with insects. We are not really inventing anything, we are not making the black fly soldier carry out bioconversion processes that nature invented centuries ago," says the Unal professor.

For José Alejandro Villarruel, who started out as one of Barragán's students, helped found Entopro and is now one of the company's partners, this type of initiative is also an opportunity to recognize the ecosystem services provided by insects, many of which life on this planet, and also to draw attention to a group that is currently highly endangered.

"We are talking about losses of insect biodiversity that we have not even been able to describe. The fact that we do not know them does not mean that they are not important. Nature has gone through an evolutionary process to reach a natural balance, and all species play their role in the environment. If we interfere with these species that we do not know, we will change the balance more and more until we reach a point where it will not be sustainable, no matter how many chemical processes we use to control pests or to add nutrients to the soil for cultivation. It will not be enough because these small creatures are not there to carry out all these activities," Villarruel points out.

Today, these small animals, although they do not receive as much attention as large mammals, are also victims of the loss of biodiversity that the planet is suffering. Studies have warned that nearly a third of insect species are threatened with extinction, and that every year another 1 percent is added to the list. An irreversible path unless decisions are made to change the way we produce food today.

ALEJANDRA LÓPEZ PLAZAS

Science journalist

@malelopezpl