Den Dotter

Den Dotter is a nature reserve of roughly 205 hectares straddling the municipalities of Erpe-Mere (in the village of Aaigem) and Haaltert (in the village of Heldergem), in the East Flemish Denderstreek region of Belgium. The reserve lies just southwest of the town of Aalst and ranks among the most valuable natural areas in this part of Flanders.

Where does the name come from?

The reserve takes its name from the marsh marigold, known locally as "dotterbloem" — a bright yellow flower that blankets the wet meadows and thickets each spring wherever mineral-rich groundwater rises to the surface. This seasonal display of flowering meadows has become something of a signature image for the whole area.

What does the landscape look like?

At the heart of the reserve runs the Molenbeek-Ter Erpenbeek stream, whose name recalls the many watermills that once operated along its course. The terrain is markedly varied: the lower parts of the valley hold wet meadows, land once used for hay-making, thickets, and swamp forest growing on ground that floods periodically. Higher up, on drier and more undulating ground, open fields have been farmed by local communities for centuries. This mix of wetland and farmland gives Den Dotter an unusually rich landscape for such a compact stretch of Flanders.

What plants and wildlife live here?

The reserve is known for its species diversity, with as many as 320 different plant species recorded within its boundaries. Alongside the marsh marigold, several other, rarer plants typical of river valleys can be found here. Birdlife is equally abundant: the faster-flowing stretches of the brook attract grey wagtails and kingfishers, the wooded sections host hoopoes and hobbies, and the pollarded willows along the fields shelter little owls. The open farmland, in turn, provides habitat for typical field birds such as linnets and skylarks.

How is the reserve managed?

Den Dotter is looked after by Natuurpunt, Belgium's largest nature conservation organisation. Management work includes clearing fallen poplars, replanting newly acquired plots with native trees and shrubs, mowing the various grasslands and removing the cut grass, and maintaining the small ponds scattered across the site. As the reserve's own managers put it, part of the management is simply knowing when to leave a patch of nature well alone.

How can visitors explore Den Dotter?

An 11.3 km node-based walking route winds through the undulating landscape between Haaltert and Erpe-Mere, taking in the reserve and its surroundings. Visitors after a shorter outing can follow the 2.8 km yellow route, which is also suitable for pushchairs, or choose between a 5.9 km blue route and an 8.4 km red route for a longer walk through the area.

Frequently asked questions

Where exactly is Den Dotter located? The reserve sits on the border between the municipalities of Erpe-Mere and Haaltert, in the villages of Aaigem and Heldergem, southwest of the town of Aalst in East Flanders.

How large is the reserve? Den Dotter covers around 205 hectares in total, although the section around Heldergem itself is sometimes described as a smaller part of the wider complex, spanning a few dozen hectares.

Are there marked walking trails through Den Dotter? Yes — an 11.3 km node-based route and three shorter colour-coded trails (yellow, blue and red) offer options for visitors of different fitness levels and available time.

What wildlife can be seen in the reserve? The area supports numerous bird species, including kingfishers, grey wagtails, hoopoes, hobbies and little owls, as well as farmland birds such as skylarks and linnets.