On Earth Day (22 April 2025) the Frontiers Planet Prize jury of 100 leading sustainability scientists selected Prof Dr Robert Arlinghaus (Leibniz-Institute of Freshwater Ecology & Inland Fisheries / Humboldt-Universität zu Berlin) as Germany’s National Champion. The title recognises research with proven potential to help keep humanity within the planet’s safe operating space—with no direct funding attached, but enormous international visibility and access to a global innovation network.
What is the BAGGERSEE project?
Scope & timeline: 2016 – 2022, 20 gravel-pit lakes across Lower Saxony.
Method: before-and-after / control-impact experiment comparing (a) conventional fish stocking with (b) habitat restoration—especially new shallow-water zones and bundles of coarse deadwood.
Sampling effort: ~160 000 fish surveyed; 40 000 individuals PIT-tagged for growth and survival tracking; complementary monitoring of aquatic plants, dragonflies, amphibians and water chemistry.
Stakeholders: dozens of angling clubs in the Anglerverband Niedersachsen e.V.; hundreds of volunteer anglers helped implement measures and collect data, illustrating citizen science at ecosystem scale.
Funding & team: trans-disciplinary consortium led by IGB and AVN, financed by BMBF/BMUV/BfN under Germany’s National Biodiversity Strategy.
Key findings (published in Science)
Creating shallow-water habitat consistently boosted juvenile and adult fish abundance.
Adding deadwood delivered lake- and species-specific gains but less than shallow zones.
Fish stocking failed outright: no measurable improvement in target populations.
Habitat restoration simultaneously enhanced macrophytes and dragonflies, proving ecosystem-wide benefits.
Why the National Champion title matters
Being one of only 19 National Champions worldwide means the BAGGERSEE study now serves as a flagship example of nature-based solutions for inland waters. It demonstrates—at real-world scale and with rigorous controls—that restoring lost habitats can outperform decades-old management dogma, informing policy, angling practice and conservation funding far beyond Germany.
“We have put the likelihood of success of ecosystem-based measures on a scientific footing. It is essential that habitat improvements target the most limiting factors.” — Robert Arlinghaus