Rewilding

To understand what rewilding is and how this restoration of ecosystems damaged by humans is carried out, it is useful to know the three principles on which it is based.

• The reintroduction into the habitat of the so-called "keystone species", such as predators at the top of the food chain and large herbivores, which, in addition to restoring biodiversity to the ecosystem, help to maintain the ecological balance. In the case of predators, because their absence would have consequences throughout the chain, and in the case of large herbivores, because by eliminating grasses they help maintain the natural balance.
• The recovery of natural functions, such as predation and competition between animal species, or seed dispersal by carnivorous birds or mammals, so that these processes can develop without human action.
• The reduction of human intervention, to eliminate as much as possible direct human management. This principle of rewilding may involve, in addition to the reduction of human action, the elimination of infrastructures or the replacement of harmful economic activities with environmentally friendly ones.

Consequently, rewilding has the effect of returning the ecosystem to a state close to the original one, in which these processes were carried out without the need for human intervention. 

Rewilding is quite a recent conservation strategy, which originated just over 30 years ago and which today has become a global trend.

The term rewilding was first used at the start of the 90s by the environmental activist David Foreman, editor of the ‘Wild Earth’ magazine and founder of the Rewilding Institute in 2003. Foreman based his rewilding concept on the introduction of animal species, especially large carnivores, into habitats they had disappeared from. It wasn't just about recovering biodiversity, but doing so with a sufficient population to allow these ecosystems to recover their autonomy.

In 1998, conservation biologists and researchers Michael Soulé and Reed Noss published the article 'Rewilding and biodiversity: complementary goals for continental conservation’, in which as well as using the term coined by Foreman, they recovered his theory of the introduction of large carnivores.

Although this strategy was a novelty in the field of conservation, the term rewilding remained unknown outside of academia until 2020, when science popularizer David Attenborough used it in 2020 in the documentary 'A Life on Our Planet'. 

Nature-based solutions are diverse. As well as those previously mentioned, rewilding techniques include the following:

• Restoration of degraded areas. In severely affected areas, restoration can involve the removal of debris, remodeling of the terrain, and the planting of native plant species.
• Removal of invasive species. Non-native species can cause damage to local ecosystems. The eradication of these invasive plants and animals helps to restore the ecological balance and favors the conservation of native species.
• Soil recovery. Techniques such as reforestation, the use of cover crops, and the reduction of compaction improve soil quality and thus restore soil fertility.
• Reconnection of fragmented habitats. The creation of ecological corridors allows the movement of species between previously fragmented habitats and, as a result, migration and genetic exchange between animal populations. For example, through the establishment of underground tunnels or green bridges over roads.
• Extensive stockbreeding and grazing. As with large herbivores, extensive stockbreeding and grazing can improve soil quality, eliminate weeds and thus fires, and promote vegetation regeneration.
• Recovery of aquatic ecosystems. The rehabilitation of wetlands, the removal of disused dams, or the restoration of river meanders to optimize the natural flow of water are also ways to restore aquatic ecosystems and thus their biodiversity.
• Controlled fires. The use of controlled fires is a technique used to manage vegetation and conserve certain types of ecosystems, such as meadows and scrublands. These fires can help eradicate invasive species, encourage the germination of native seeds, and preserve biodiversity.