Wildlife in the woods, on the heath and over the fens

What makes the reserve so rich

Most Dutch wildlife lives in fragments — patches between fields, ditches, roadside strips. The Oisterwijkse Bossen en Vennen, by contrast, is a thousand connected hectares that has been undisturbed for over a century. That continuity matters: species that need quiet to breed, large home ranges or specific habitats have somewhere to be. Add the wetter heath of Kampina next door and you have a meaningful piece of working ecology.

Mammals

Red deer and roe deer both live in the reserve. Roe are smaller, browner and more often seen — usually alone or in twos, slipping between the trees in early morning or late evening. Red deer are larger, herd more, and are most dramatic in autumn during the rut, when the stags' roar carries across the fens at dusk. Walk quietly, stay off-trail-edges, and you will see them.

Foxes are widespread but shy. Wild boar are not resident here (they live in the central Veluwe and the south); the rare sighting tends to be a wanderer. Pine marten, badger and stoat are present but rarely glimpsed. Bats are everywhere on summer evenings — pipistrelle, noctule and Daubenton's hunting over the open water.

Birds

The reserve is on most Dutch birders' regular round. The list of notable residents and visitors includes:

• Kingfisher — a flash of blue over the brooks and fen edges. Best chance: still mornings, near the edge of the Voorste Goorven.
• Great spotted, green and black woodpeckers — all three breed here. The black woodpecker is loud, large and unmistakable; its laughing call is one of the reserve's signature sounds.
• Common crane — increasingly seen on passage; some pairs now breed in nearby reserves.
• Honey buzzard, sparrowhawk, goshawk — all three raptors hunt the woods.
• Tawny owl — listen at dusk in winter.
• Cuckoo — arrives in April; calls through May and June.
• Crested tit, treecreeper, nuthatch — characteristic small woodland birds.
• Stonechat on the heath, perched on top of the gorse.
• Heron, little egret, great cormorant — on the fens and reed edges.

"The laughing call of the black woodpecker is the reserve's signature sound."

Dragonflies, butterflies and other insects

The fens are world-class for dragonflies. Specialists come in June and July to tick off the emperor, four-spotted chaser, keeled skimmer, downy emerald and the rare moorland hawker. The peripheral heath is good for the silver-studded blue butterfly, which depends on heather, and a strong colony of green hairstreak. In high summer the floating bog produces clouds of damselflies.

Reptiles and amphibians

The reserve has a healthy population of adders, the only venomous snake in the Netherlands. They are shy and rarely seen, but if you sit quietly on a sunny heath edge in spring you might find one basking. Bites are vanishingly rare and treated effectively. Grass snakes and slow worms also live here; sand lizards bask on south-facing trail edges. Frogs and toads breed in the shallower fens — moor frog, common frog, common toad and natterjack — and several newt species are present in the smaller pools.

Plants

The reserve's habitats are defined by what grows in them: bell heather and ling on the dry heath; cross-leaved heath and cotton grass in the wetter parts; white water lily, bog asphodel and sundew in and around the fens; blueberry and bracken under the pines. The unusual acidic, nutrient-poor soils of the area sustain a flora that is increasingly rare elsewhere in the Netherlands.

When to see what

Watching with respect

Stay on the paths even when you see something interesting. Keep dogs on a lead — they panic deer and put up ground-nesting birds. Use a long lens rather than approaching wildlife. In ground-nesting season some paths are closed; please respect those closures. Drones are not permitted in the reserve and cause obvious disruption.