Windows of Opportunity

The "Kleine Pechlibelle" is one of twenty-five species that ecologist Felix Zitzmann and his colleagues from the University of Hanover found on their test site, making it the most significant waterbody for dragonflies in the local area. Their study, published in July, is part of a wider research effort to understand the role rewetted peatlands, a type of wetland with organic soil made of decaying plants, can play as habitats for insects and other animals when they are simultaneously used for crop cultivation. As an alternative to conventional farming, paludiculture attempts to balance human and ecological needs - and wildlife flourishing is one important factor in this equation.

That mires are far from barren "wasteland" has become more widely appreciated as their critical role to climate protection is better understood. Historically, almost all of the muddy expanses that once spanned the North German Plain were drained to grow crops and graze sheep and cattle. Once dry, peatlands begin to emit the large amounts of carbon they store when wet: though making up just 7% of Germany's arable lands, they are currently responsible for 37% of sector emissions, the Umweltbundesamt reports.

"The main reason for paludiculture is climate protection, but it would be an even more sustainable land use if paludiculture also had some benefits for biodiversity," Zitzmann says. "We've got a climate crisis, but we've also got a biodiversity crisis. In the best case, these measures go hand in hand."

Natural mires are true biodiversity hotspots and home to many specialised species which depend on wet and nutrient-poor environments to thrive. To evaluate if paludicultures can restore some of these conditions while keeping the productive use of the land, observing dragonflies is especially instructive, according to Alexander Drexler. He researches the intersection between paludiculture and biodiversity at the University of Greifswald.

Not only has peatland drainage had devastating effects on the climate but also on those species that evolved alongside its unique and delicate conditions.

"Dragonflies are valuable indicator species," he says. "As semi-aquatic insects that undergo both aquatic and terrestrial phases in their life cycle, they reflect the health of the entire ecosystem."

Upon emerging from their underwater larvae life, dragonflies shed a translucent skin called exuviae. Collecting these was one of the key ways for Zitzmann and his research team to determine which species found the paludiculture's habitat quality suitable to lay their eggs, and stable enough for their larvae to mature. Of the twenty-five types of dragonflies counted in three years, twenty were certainly or probably reproducing on the site at least once. Apart from Ischnura Pumilio, three of these are red-listed as endangered in Germany or Lower Saxony.

One such measure could be to reserve small plots of land within the paludiculture as "dragonfly windows": permanent sanctuaries maintained to be dragonfly-friendly. The University of Hanover study suggests that this may help make their results more widely applicable. And for the "Kleine Pechlibelle," a species so unlucky in finding a home, such windows could offer an opportunity to build back enough of its population to make the peatlands glimmer once more.