Recovering local biodiversity, how do you do that?
Utrecht University aims to reestablish 20 icon species by 2035
Prior to the 1960s, badgers, grass snakes and lapwings were abundant in the agricultural landscape that is now Utrecht Science Park. But as roads and buildings encroached upon the area, these populations began to retreat. Now, a dedicated team at Utrecht University is inviting them back. What does it take to restore biodiversity in an entire landscape?
On an ordinary spring day just a few decades ago, walking across Utrecht Science Park meant you could find over 100 meadow birds nesting. Species like the black-tailed godwit, skylark, redshank and partridge were common, and have since disappeared from USP. Their numbers have dwindled so drastically that they are now on the red list of breeding birds in the Netherlands, a stark reminder of how quickly an species can all but vanish when their habitats change.
There is one main factor driving the decline of meadow birds and many other animal and plant species: the deterioration and fragmentation of their habitats. So by restoring the ecosystems where these species once thrived – and interconnecting them, a team at Utrecht University hopes to bring them back from the brink.
We will show that restoring local biodiversity is possible.
An Ambitious Restoration Project
“The loss of biodiversity at Utrecht Science Park, like everywhere else in the world, is disheartening. But we will show that restoring local biodiversity is possible,” says Dorinne Raaimakers, Programme Manager of Biodiversity at Utrecht University. The team aims to reestablish twenty icon species by 2035, including badgers, little owls, roe deer and weatherfish. These species serve as indicators for the state of biodiversity in the area. If the Wall Brown butterfly, another icon species, is seen around, it means conditions have also become suitable for other pollinators to return.
“We don’t just want to see these species pass by at the Science Park; we want them to stay, find food and nest here too,” emphasizes Raaimakers. According to her, recovering these species is important because of their own intrinsic value as living beings, but also for their contribution to biodiversity and ecosystem functioning. “Biodiversity is crucial for ecosystem services such as climate control, flood protection and food security. Insects pollinate fruit trees and other crops,” she explains. “Also, a green environment provides health benefits for the staff, students and patients that visit the Science Park. Creating the right environmental conditions for these species is therefore vital to our own well-being.”
Of course, recreating entire ecosystems for such a diverse group of species takes some landscape engineering at first. How did the team know which habitats to restore, or which species to prioritise? “Restoration needs to be ecologically sound,” says Raaimakers. “That’s why Utrecht University has a Biodiversity Council, whose knowledge and expertise helped determine which species are characteristic for the area and most promising for recovery.”

Sustainable development
Professor of Land Use and Biodiversity at Utrecht University and chair of the Biodiversity Council, Merel Soons, explains their approach: “We reviewed studies describing the area’s biodiversity before it became the Utrecht Science Park we know today. Based on the species documented to be present, we inferred the habitats that supported these species, considering soil conditions, climate and hydrology of the area,” says Soons.
When records fell short, expert judgement filled in the gaps. For example, while bird records were extensive, those for reptiles and amphibians were not. The team identified six key habitats necessary for the twenty icon species to survive. For example, common pipistrelles (or dwarf bats) need buildings for nesting, while roe deer love forest-like areas with open fields. Crested newts, grass snakes and the scarce chaser dragonfly require open water and wide aquatic-terrestrial transition zones.
Connecting the Dots
But equally important as restoring habitats is interconnecting them. “One of the main threats to populations such as badgers or newts surviving in the wider area is that they have become separated from each other,” says Soons. “Today, the three green estates that border Utrecht Science Park (Sandwijk up north, Amelisweerd to the south, Oostbroek to the east) function ecologically as islands. Science Park infrastructure and buildings form a physical barrier which many wild species do not or cannot pass. To welcome more biodiversity, we not only need to improve the conditions at the Science Park; we also need to reconnect the nature areas surrounding it.”
The goal, endorsed by UU’s Strategic Plan, is to transform Utrecht Science Park into a network of blue and green corridors, providing safe passage for wildlife. “Tree tops form runways for forest species to move from branch to branch; ponds create corridors for (semi-)aquatic species; and herb-rich grasslands attract and provide habitat for pollinators, and provide a linear structure along which they can move,” explains Soons.
Still, the process of recovering species can be slow. “Take the crested newt,” says Soons. “We’ve designed a landscape corridor consisting of ponds to connect Amelisweerd and Oostbroek for this species. But we don’t expect that one newt individual will travel from pond to pond in one go. Most probably, one newt may reach the first pond, lay its eggs, and start colonizing the place. From there, a new generation may reach the next pond, and the next, and so on.”
Weighing of interests
Restoring these key habitats requires careful planning. “Where should the ponds be located? If they are too close to the river, fish may eat the crested newt eggs, defeating the purpose,” Soons elaborates. “Collaborating with experts in the field has been of incredible help to weigh in all these considerations.”
Sometimes, compromises are necessary. "Hedgerows may need to be low and broad for some species but tall and narrow for others. We choose dimensions that attract the most species," says Soons. "Gaps between hedgerows can be problematic, but sometimes unavoidable due to existing roads, ditches or field entrances."
But those challenges, Soons is eager to point out, are what makes this project an inspiring model for other biodiversity restoration efforts. "Restoring nature itself isn't the hard part; it's doing so in an area where various interests coexist," she says. In this way, the Utrecht Science Park is representative for other landscapes in densely populated areas. “By working together with other stakeholders, we designed restoration efforts for the local situation. Especially important, and even crucial, is our collaboration with De Tolakker, the teaching farm at the Faculty of Veterinary Medicine. Together, we are exploring ways of cultivating herb-rich grasslands in at least 20 percent of the meadows. That will provide a new habitat for many wild plants and animals, and ultimately improve biodiversity.”
“By doing all this, we are turning Utrecht Science Park into a ‘living lab’ for biodiversity recovery that is representative for large parts of the country. We are exploring best practices and win-win situations that can be extrapolated to real world conditions,” Soons says. “Therefore, it is also very important that we monitor the success rate of our activities and evaluate its impact on all inhabitants of the Utrecht Science Park and beyond, no matter which species they belong to. This way, UU scientists can practice what they teach and learn from interactions in the living lab. It’s definitely more challenging, but it is also more valuable.”
More information?
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