Understanding the impacts of rewilding on biodiversity and bird communities

Rewilding is an emerging conservation strategy aimed at restoring natural processes and enhancing biodiversity by reducing human intervention and fostering self-sustaining ecosystems. By reinstating ecological dynamics such as predation, herbivory, and natural disturbances, rewilding can reshape landscapes, influencing species distributions and habitat connectivity.

This is particularly relevant for bird diversity, as changes in habitat structure—whether through forest expansion, land abandonment, or reintroducing ecosystem engineers—can create both opportunities and challenges for different bird communities.

The impact of changing land use on biodiversity

In Europe, shifting land use patterns, including the abandonment of traditional agricultural lands, have led to increased forest cover, often altering bird assemblages. While some forest birds benefit from this expansion, open-land and farmland birds—many of which are in decline—face habitat loss and reduced foraging opportunities.

Rewilding is often proposed as a new way to manage abandoned farmland but such strategies must be carefully implemented to balance biodiversity conservation across landscapes. Understanding which bird species are sensitive to the changes in habitat structure that are linked to rewilding can help assess how landscapes can benefit from rewilding.

Differences in vegetation structure between planted forest (left) and natural forest (right) in central Sweden. Pictures: Tristan Bakx.

For example, in certain Mediterranean contexts, biodiversity indicators can help separate the forests by their potential for conservation. Forests on previously abandoned farmland are often inhabited by poor forest species communities and could be reverted to open habitat that supports farmland bird populations and reduces wildfire connectivity, mitigating large-scale fire risks. In contrast, Mediterranean forests with rich species communities can be identified and prioritized for protection to maintain their ecological value.

Measuring impacts on biodiversity

A landscape of abandoned and re-cultivated farmland (mostly almond and olive groves) in Catalonia, Spain, resulting in a variety of vegetation structure types. Picture: Tristan Bakx

By integrating biodiversity monitoring with rewilding frameworks, conservationists can develop adaptive management strategies that maintain diverse bird communities while enhancing ecosystem resilience. Understanding how structural changes in the landscape impact bird diversity will be crucial in guiding these efforts, ensuring that rewilding contributes to ecological balance rather than unintended biodiversity losses.

Join our webinar to learn more

As part of the wildE project, researchers from CREAF and associated researchers, in collaboration with other wildE members and the Biodiversa+ project SPEAR, are studying this relationship between bird communities and vegetation structure and changes. In an upcoming webinar, early career researchers from CREAF will present their work on biodiversity in forests exposed to environmental change. They will review the state-of-knowledge, present their ongoing work, and discuss the impacts of their work on rewilding.

First, Gabri Miret will present about using forest structure information and bird monitoring data to identify potential biodiversity indicators which could help assess forest conditions. Second, Dr. Tristan Bakx will present about the impacts of changing forest disturbance regimes on European bird communities.