Climate change will produce ever longer and more severe droughts in Canary Islands. Climate projections warn that aridity will increase in the archipelago in the coming decades due to greenhouse gases and global warming. These scenarios point to the desertification of the vast majority of the islands, a phenomenon that Lanzarote already suffers from, being more arid and having less rainfall than the rest.
Faced with this climatic scenario, the non-profit foundation Fénix Canarias proposes to recover an ancestral technique that exists in few places in the world: the gavias. "They are an example of how a sustainable use of the territory can turn a problem into a resource," explains the forest engineer and technical director of Fénix Canarias, Roberto Castro during an interview with La Voz.
But first, what is the situation in Lanzarote? The continuous passage of Atlantic storms and fronts in recent months has made the landscape of Lanzarote flourish, but the island has not stopped suffering the consequences of the drought. A study published by the journal Nature in 2023 reported that Lanzarote had registered a decrease in hydrological drought, meaning it had managed to maintain better rainwater reserves than in previous periods. However, if other conditions were analyzed, such as evapotranspiration, the research warned: droughts are becoming more frequent, longer, and more severe.
Therefore, relating drought solely to a lack of precipitation leaves several factors out of the equation. At this point, the soil's and plants' capacity to capture and filter water, or the amount of rainwater that ends up evaporating, comes into play.
Last March, when the Canary Islands were on red alert for rain and flood risk due to the passage of storm Therese, was the wettest since 1961, when data began to be collected, according to the State Meteorological Agency. This period broke a decade of drought that the archipelago was going through.
"Our vegetation, both coastal and midland, or our palm groves, as we have in Haría, are accustomed to recurring cycles, some wetter periods and others drier," explains the forestry engineer and technical director of Fénix Canarias, Roberto Castro. This expert points out that the archipelago had been accumulating a drought period and that this wet period alone is not enough to preserve the ecosystems. "Our ecosystems have had a respite, but this by no means assures us that they can survive the future," he warns.
The forestry engineer points out that the lack of water means "a debacle" in ecosystems and causes "premature death" of certain specimens, such as palm trees. "In great extinctions, the largest specimens always start dying, and then you begin to see how the tabaibas do not spread or the verodes do not regenerate," he continues.
The Canarian vegetation can be lost, as will also happen with the soil and its nutrients. "If very heavy rains come, all that land that does not have vegetation to support it ends up going to the sea". Thus, he indicates that this layer of fertile land takes hundreds to thousands of years to form and only a few decades to be lost, driven by torrential rains and wind.
In the complexity of ecosystems, without water there is no vegetation, without vegetation there is no substrate, and without substrate new specimens cannot be born. Faced with this situation, the scenario is not only dramatic for plant species but also affects insects and birdlife, especially on an island in Lanzarote where the lack of trees forces birds to nest on the ground.
To avoid the loss of soil nutrients, but also due to intense or torrential rains, Fénix Canarias proposes two initiatives: recovering traditional architectural elements and creating gabions.
The past teachings and the seagulls
The lack of rain in Lanzarote and the need to cultivate its fields led the island's population to explore different methods for capturing this fundamental resource. Among them, the gavias, plots of land for cultivation, bordered by earth and irrigated by flooding with rainwater from ravines. These constructions, present in Lanzarote and Fuerteventura, are similar to those historically carried out in North Africa.
"When the ravines ran, part of that water that ran was channeled towards flat areas, close to the ravine and water reservoirs were created," explains Castro, who delves into the importance of the land having nutrients that allow for a sponge effect against the rain. "Part of the nutrients or sediments that could have been eroded uphill ended up in the gavias and, therefore, there was a renewal of sediments and nutrients, it had water and dryland crops could be planted," he adds.
With the torrential rains of April 2025, the gavia of Las Cabreras reappeared, in the town of Tahíche (Teguise), where hundreds of migratory birds could be seen stopping to rest on their way through the island.
Fénix Canarias studied in Lanzarote and Fuerteventura during the years 2024 and 2025, through a project financed by the Biodiversity Foundation, ancestral techniques for collecting water. Among them, they delved into the gavias. "The gavias have coexisted with the ecosystem, with the avifauna itself, and some steppe birds for years after the gavia was cultivated and harvested, they used them for feeding and as nesting or shelter areas," adds the technical director of the non-profit association. The abandonment of these infrastructures has caused some steppe bird populations to be reduced.
For the moment, Fénix Canarias proposes a project for the recovery of gavias, in which they can study the progression of ecosystems and carry out scientific monitoring of steppe birds, for which it seeks funding, without the need to build new ones. Specifically, its proposal is to restore gavias near the nesting areas of the Canarian bustard (Chlamydotis undulata fuertaventurae), a species native to the island, which is in danger of extinction. At the same time, it proposes that the waters accumulated in the gavias can be used, as in the past, for agricultural use.
The jackdaws, a layman in nature
Next to the groynes, Fénix Canarias proposes the creation of gabions in the ravines to temporarily retain water and reduce the energy with which it descends. These gabions are modern infrastructures made with wires that are filled with stones from the ravine itself and that allow "laminating the water" so that the pressure decreases.
"If we place a series of gabions one behind the other, every 400 or 500 meters, we achieve that in the event of heavy rainfall, the water arrives more slowly, much more slowly," indicates Castro, achieving that "if 50 liters fall in an hour, with the gabions we achieve that the 50 liters, instead of falling in one hour, fall in six."
Facing the gabions, the gabions are not used for agricultural purposes, but rather it is the vegetation itself that ends up "colonizing" them and growing on the meshes.
For example, in the case of Arrecife, when heavy rains flood the city in a few minutes, this non-profit foundation indicates that gabions increase the width of the ravines and help prevent flooding. At the same time, it explains that by having this mesh, the sediment and nutrients from the soil are not washed away but are retained.