Stubbe Sø Nature Reserve: A Detailed Atlas of Protected Landscapes in Region Midtjylland

Human shaping of the Stubbe Sø landscape goes back at least to the closure of the original fjord system and the gradual transformation of the surrounding heath into farmland and forest, but the modern protective history of the area begins in the twentieth century. In 1963, Stubbe Sø and surrounding lands totaling 381 hectares were placed under a nature conservation order to protect their landscape values.

The Danish nature conservation organization Fugleværnsfonden acquired a 23-hectare bird reserve on the northeastern side of the lake, which remains publicly accessible and continues to play a role in managing disturbance around important waterbird habitat. The reserve sits within a broader pattern of formal protection that has accumulated over the following decades.

In 2011, the first Natura 2000 plan for the site was adopted, requiring Syddjurs Kommune and Naturstyrelsen to draw up binding action plans for its implementation. The plan was coordinated with the water plan for the Djursland catchment and has since been extended and refined in subsequent planning periods. The inclusion of Stubbe Sø within Nationalpark Mols Bjerge has further integrated the lake into a larger framework of landscape-scale protection and management in central Djursland.

Stubbe Sø sits in a gentle, low-lying terrain of lakes and mires northeast of the more pronounced uplands of Mols Bjerge. This part of Djursland consists of broad, shallow valleys and basins shaped by glacial processes and historically influenced by the sea, which once penetrated inland through a fjord that has since become the present lake.

The lake itself is large and shallow, with an open expanse of water that reflects the surrounding forest and sky. Along its margins, a narrow, lighter zone of alder and birch gives way abruptly to the darker stands of coniferous forest that now cover most of the visible landscape. This contrast between the open, light-fringed shoreline and the dense, dark plantations is one of the defining visual character traits of the area.

Around and beyond the forest, the landscape includes mires, freshwater meadows, and patches of dry heath on the older sandy and gravelly soils left by glacial activity. Together with the lake, these features create the varied wetland-mire-edge mosaic typical of this part of eastern Jutland.

The ecological character of Stubbe Sø is defined by the combination of a shallow, nutrient-rich lake with mires, freshwater meadows, stream corridors, and extensive surrounding forest. The lake supports aquatic vegetation typical of nutrient-rich Danish lowland lakes, and it is bordered by alder-birch swamp woodland in the wettest shoreline zones.

The Natura 2000 designation for the site lists a range of natural habitat types that the management plan aims to maintain in favorable condition. These include hard-water charophyte lake habitat, nutrient-rich lake habitat, watercourses, dry acidic grassland, periodically inundated meadows, and rich fens. Forest habitats of particular concern include beech forest on mor soils, oak mixed woodland, pedunculate oak scrub, and alder-ash swamp forest.

Mire and bog habitats are a special focus of the conservation strategy for the area, with the stated objective of safeguarding existing raised bogs, achieving a high state of conservation for them, and expanding them where natural conditions allow. The mosaic of open water, marshy fringes, and forested slopes creates a diverse habitat gradient that supports a wide range of breeding, staging, and wintering species.

Stubbe Sø is primarily significant for its waterbirds. The lake is an important breeding site and, more importantly, a major staging and resting area for large flocks of geese, ducks, grebes, and mergansers that use its shallow, productive waters. The combination of open water and sheltered shoreline makes it attractive to a wide variety of species throughout much of the year.

Raptors are regularly observed around the lake, with white-tailed eagles and ospreys among the more notable visitors that take advantage of the fish-rich waters and the open sightlines over the surrounding landscape. The mix of open water, marsh, and forest edge provides a range of hunting opportunities for different predator species.

Among mammals, otter has been recorded around the outflow of the lake into Havmølle Å, reflecting the connectivity of the lake and stream system and the importance of intact shoreline habitats for this species. The combination of protected aquatic habitat and adjacent mire and forest contributes to the broader fauna of the Nationalpark Mols Bjerge landscape.

Stubbe Sø is protected at multiple levels. Nationally, the lake and surrounding land were placed under a nature conservation order in 1963 to protect their landscape values. A 23-hectare bird reserve on the northeastern shore, owned by Fugleværnsfonden, provides additional protection and manages public access in sensitive areas.

At the European level, the area is designated as EU Natura 2000 habitat area number 48, with a collection of priority and non-priority habitat types listed in its formal designation. A Natura 2000 plan adopted in 2011 set binding actions for Syddjurs Kommune and Naturstyrelsen, with particular emphasis on securing raised bogs in good condition and expanding them where natural conditions allow.

The site also lies within Nationalpark Mols Bjerge, integrating Stubbe Sø into one of the most significant landscape-scale conservation frameworks in Denmark. Together these instruments aim to preserve the lake's value for waterbirds, maintain the mire, meadow, and forest habitats in favorable condition, and coordinate land and water management across the broader Djursland catchment.

Stubbe Sø is fundamentally a natural rather than cultural site, but it sits within a landscape that has been shaped over centuries by rural land use. The original heath environment around the lake was historically used for grazing and other low-intensity activity, and the later conversion of much of the heath to coniferous plantation reflects broader twentieth-century patterns of Danish afforestation.

The lake and its conservation history are also part of the identity of Djursland and of the broader Mols Bjerge region, where long-standing local interest in landscape and wildlife protection contributed to the establishment of both the 1963 conservation order and the later national park. Public access to the bird reserve and the surrounding protected landscape reflects an established Danish tradition of using such areas for quiet recreation and birdwatching.

Stubbe Sø stands out as the largest lake on Djursland and one of the most important freshwater bird sites in central eastern Denmark, with a particular reputation for large gatherings of geese, ducks, grebes, and mergansers.

Its setting within Nationalpark Mols Bjerge and its dual status as a long-protected landscape and an EU Natura 2000 habitat area give it both a strong conservation identity and a wider role in the protection of the surrounding heath, mire, and forest landscapes.

The character of a visit to Stubbe Sø varies with the seasons. Late autumn, winter, and early spring are typically the most rewarding periods for waterbird viewing, when large numbers of geese, ducks, grebes, and mergansers use the lake as a staging or wintering area, and raptors such as white-tailed eagles and ospreys may be encountered more frequently around the open water.

Spring and early summer bring breeding activity on the lake and in the surrounding wetlands, as well as fresh green growth in the alder-birch shoreline fringe, contrasting with the darker coniferous forest that dominates the wider landscape. Midsummer tends to be quieter for large flocks but offers the most pleasant conditions for exploring the surrounding woodland and mire edges.