The natural dispersion of this true river engineer to Portuguese territory represents not only the return of a species that was once locally extinct but also one of the most significant steps in the aquatic rewilding of our rivers in Portugal.
The last known record of beavers in Portugal probably dates back to the end of the 15th century. Since then, this emblematic species has disappeared from our rivers, a victim of intensive hunting and the destruction of its habitat.
However, after two decades of population recovery in Spain, and recently with signs of documented proximity to the Portuguese border confirmed in several monitoring actions carried out in the field by Rewilding Portugal, unequivocal signs of its presence in national territory have finally been found. Gnawing marks began to appear on trees and watercourse manipulation structures, typical of the activity of this species, and the timely placement of photo traps confirmed, in video and photographic form, the presence of a young adult individual, already in Portuguese territory.
In 2023, the newspaper Expresso already reported that the beaver was about 150 meters from the Portuguese border, with consistent records in the Arribes del Duero Natural Park, close to the border with Portugal. . Rewilding Portugal already warned in that same article that its return would only be a matter of time – and preparation. And what was said at the time came true: the beaver is back. The preparation we were actively asking for is not. “We have been aware of this progress for some years, and now it is with great excitement that we confirm its return. The beaver is a natural ally in restoring the health of our rivers and wetlands and has a fundamental role to play in our river ecosystems,” says Pedro Prata, Team Leader at Rewilding Portugal.
The beaver is a true ecosystem engineer. Its instinctive behaviour of building dams, digging channels and modifying river banks profoundly transforms the landscape, bringing it diversity, water retention and life. These changes promoted by the beaver have profoundly beneficial effects on the biodiversity and ecological resilience of riverside habitats.
By building dams, beavers create small wetlands, marshes and areas of still water – habitats that are home to a huge variety of species: amphibians, aquatic insects, water birds, fish and small mammals. A true contribution to enriching the biodiversity of these watercourses and their surroundings. These wetlands also act as natural water filters, retaining sediments and pollutants and reducing the speed of surface runoff, which mitigates the effects of flooding and erosion.
“We are talking about a species that provides ecological services that no modern equipment can replicate with the same efficiency and scale, without costs and without bureaucracy that is never overcome. The beaver improves water quality, creates refuges for other species and helps us combat phenomena such as drought and fires”, emphasizes Pedro Prata.
On the other hand, by raising the water table level on riverbanks, beavers increase water retention in the soil, something particularly relevant in contexts of prolonged drought and desertification – two phenomena that are increasingly present in the interior of Portugal. Their structures help to store water in the territory, releasing it gradually throughout the year. Furthermore, there is growing evidence that habitats created by beavers act as natural defense lines against forest fires, by maintaining permanently wet areas that break the advance of fires and provide shelter for numerous species during the most critical periods.
Key species
The concept of rewilding, or renaturalization, has gained prominence in recent years as an innovative and systemic approach to restoring ecosystems through the return of key species, giving nature and all its components the time and space needed to evolve without human intervention. The beaver is undoubtedly one of the best European examples of this philosophy in action. Its recovery through natural expansion represents an invaluable boost for Portuguese rivers, many of which are degraded, channelled, artificialized and ecologically poor.
As Rewilding Portugal advocates, the return of the beaver should not just be tolerated – it should be used as a lever for positive ecological transformation. It is and a concrete opportunity to apply the principles of truly functional rewilding on the ground: restoring natural processes, giving nature back its leading role and creating more vibrant, resilient and biodiverse landscapes.
“The return of the beaver to Portugal is a symbol of hope and change. It shows that if we leave space and time for nature, it responds. It is now up to us to ensure that this return is welcomed and protected”, reinforces Pedro Prata.
Coexistence
Of course, the return of the beaver brings challenges. Its presence can sometimes cause impacts on riverside plantations or infrastructures that are poorly adapted to the natural dynamics of rivers. However, experiences in other European countries demonstrate that coexistence is possible and desirable, through simple and effective mitigation measures. Information, dialogue with local communities and technical support are essential to ensure that the return of this species is seen as good news – and not as a problem. In Sweden, for example, the beaver was reintroduced in the last century and financial compensation programs were created for farmers and forest owners affected by floods caused by dams. In Germany, Beaver Managers emerged who are able to mediate conflicts between beavers and human activities, installing water level control devices (e.g. pipes in dikes to regulate the height of the water without destroying the dams) and promoting natural engineering solutions such as protective barriers next to agricultural fields and valuable trees, practices also adopted in Switzerland. Even in France, several environmental education and awareness campaigns have been carried out on the importance of the beaver, with several illustrated guides having been produced on the benefits of beavers and methods for dealing with potential problems. For this same reason, Rewilding Portugal, aware of this approach to the national territory, decided to make this discovery public and informed the competent authorities in good time and in detail, asking for preparation for this arrival and a plan to anticipate possible conflicts with local communities, acting preventively and not reactively and immediately creating conditions for a return of the species carried out in a prepared manner and based on positive coexistence. So far, this request has not had any effect, and no official effort has been made in this regard. Monitoring has continued, the beaver is officially back, and there is still time to support its return in a planned manner and in harmony with what already exists. Rewilding Portugal is once again open to participating in this process.
The arrival of the beaver in Portugal is a historic and symbolic milestone for nature conservation in our country. In a context of climate crisis and biodiversity collapse, it is a sign of hope and resilience of wildlife. But it is also a call to action: to protect riverside habitats, restore ecological corridors, and support the return of species that are missing from our ecosystems. Portugal now has a unique opportunity to write a new chapter in its relationship with nature. The beaver has already done its part and arrived on our territory. It is up to us to continue.