Dissertation defence (Biology): MSc Pegah Hamedani Raja
MSc Pegah Hamedani Raja defends the dissertation in Biology titled “Spatial Ecology of Species–Habitat Relationships, Applications for Conservation and Rewilding” at the University of Turku on 13 March 2026 at 12.00 (University of Turku, Natura, X lecture hall, Turku).
Opponent: Dr., University Lecturer Daniel Burgas Riera (University of Helsinki)
Custos: Professor Jon E. Brommer (University of Turku)
Summary of the Doctoral Dissertation:
How can we better protect biodiversity in a changing world?
In my doctoral dissertation at the University of Turku, I studied how animals choose their habitats and how this knowledge can help us design better conservation and restoration strategies. As forests are managed and agricultural landscapes are intensively used, many species struggle to find the conditions they need to survive. Understanding what those conditions are is the first step toward protecting them.
The first part of my research focused on two small forest birds in southwestern Finland: the Crested Tit and the Willow Tit. These birds live year-round in boreal forests and are sensitive to environmental change. Instead of relying only on traditional bird surveys, I used automated sound recorders placed across 285 forest sites. These devices allowed us to “listen” to the forest during early spring, when birds establish their territories.
The results showed that habitat features within roughly a 100-metre radius around each recording site were especially important. Crested Tits were more often found in areas rich in pine trees and farther away from human settlements. Willow Tits strongly preferred pine-dominated peatland forests. These findings highlight how very local habitat conditions can shape where specialist species are able to live.
The third part of my research moved from Finnish forests to agricultural landscapes in England. Many of these landscapes have been shaped by farming for centuries, and biodiversity has declined. I studied whether “passive rewilding” — allowing land to regenerate naturally with minimal human intervention — could help restore biodiversity under the UK’s Biodiversity Net Gain policy.
By combining land-use maps with information about deer populations, I identified areas where natural forest regeneration is most likely to succeed. The results suggest that rewilding could make a meaningful contribution to national biodiversity targets, although success depends on local conditions such as grazing pressure.
What are the key findings?
My research shows that species often depend on specific, fine-scale habitat features. It also demonstrates how modern spatial tools and acoustic monitoring can help identify important habitat features across large areas.
What new information does this research provide?
The studies provide new insights into how forest birds use habitats during the early breeding season — an important but less studied period. They also demonstrate how spatial analysis can support practical conservation decisions, from identifying key forest habitats to locating areas with strong potential for ecological restoration.
What is the impact of this research?
This research supports more precise and evidence-based conservation. It provides practical tools for identifying important habitats, guiding forest management, and planning rewilding efforts. At a time of climate change and accelerating biodiversity loss, better spatial understanding helps ensure that conservation actions are targeted where they are most effective.
By linking ecological research with real-world policy frameworks, this dissertation contributes to building more resilient ecosystems for the future.
