The Zwin: wader passage, ringing season and the stork colony
Dunlin, curlew sandpiper, ringed plover, redshank and other waders on the tidal plain; white storks breeding in and around the park (first chicks late April); autumn passerine migration ringed daily 1 Aug–11 Nov. Zwin Natuur Park, Knokke-Heist (Belgian–Dutch border), Belgium.
Best time: 20 Aug – 30 Sep and 15 Mar – 31 Jul (March to September). Where: Zwin Natuur Park, Knokke-Heist, Zwin from the Dutch side – dunes and dike at Retranchement / Cadzand-Bad (Belgium). Time of day: Waders feed on the mudflats at low tide and pack onto the salt marsh at high tide — plan around the Zwin tide and the park's 10:00–17:00 hours.
- Partly on your own
- Entry fee
- Telescope recommended
- Sound 3/5
Open it in the interactive calendarSunrise and sunset listening times for the day you pick, and the map.
When is the best time?
- Peak 1: 20 Aug – 30 Sep — Wader and passerine autumn passage
- Peak 2: 15 Mar – 31 Jul — White storks on the nests (bill-clattering, chicks)
Active from 1 Aug to 11 Nov (August to November) in a typical year.
Time of day
Waders feed on the mudflats at low tide and pack onto the salt marsh at high tide — plan around the Zwin tide and the park's 10:00–17:00 hours; ringing can be watched from 10:00. Storks clatter most at nest changeovers in the morning and evening.
- Park hours (ringing from 10:00): 10:00 → 17:00
- Dawn on the public dike (free): 30 min before sunrise → 2 h after sunrise
Depends on the tide: best around high tide. Check local tide tables.
What will you hear?
Bill-clattering of storks greeting at the nest; dunlin and redshank flocks over the salt marsh at the top of the tide; curlews; the sea behind the dunes; in autumn a steady trickle of migrating pipits and finches over the dike.
Binoculars?
Telescope recommended. The tidal plain is wide — a scope from the hides and the dike; storks are at close range on the park's nest poles.
Where to go
- Zwin Natuur Park, Knokke-Heist — Open Tue–Sun 10:00–17:00 (daily in Flemish autumn holiday); hides over the Zwin plain; daily ringing 1 Aug–11 Nov, watchable from 10:00; Zwinbus from Knokke station (1 Apr–18 Oct). Map
- Zwin from the Dutch side – dunes and dike at Retranchement / Cadzand-Bad — Het Zwin (NL) is open public dune and beach; the dike path overlooks the same tidal plain, free and open at all hours. Map
How to go on your own, and what it costs
Park entry is ticketed (€12 online in advance, €14 on the day, children 6–17 €6; 2026) and limited to 10:00–17:00 Tue–Sun; take the Zwinbus from Knokke station or drive to the park car park. For free, unrestricted access walk the dike and dune paths of the Dutch Zwin from Cadzand-Bad or Retranchement (Het Zeeuwse Landschap), open at all hours.
Cost: Zwin Natuur Park €12 adult online / €14 at the counter, €6 child 6–17, under-6 free (2026); the Dutch-side dike and dunes are free.
Free or no-guide alternative: Walk the dike and dune path of Het Zwin on the Dutch side from Cadzand-Bad or Retranchement: the same tidal plain and roosting waders, free, no hours, and you can be there at dawn.
Who runs access
- Zwin Natuur Park – weekend guided walks and migration walks (park authority) — Guided walks with park guides; 'Vogeltrekwandeling' on set October dates; ringing demonstrations.
Field-recording notes
Inside the park you are limited to its hours and hides — fine for the stork colony and the ringing station, poor for dawn. The free option is the dike and dune path on the Dutch side from Cadzand-Bad/Retranchement, open at night, with the tidal plain below; Knokke's seafront and the N49 are the noise, the beach is wide and the dunes shelter. Ringing: ask the ringers before recording near nets, and no playback anywhere in the reserve. September high tides at dawn put the wader roost at its closest to the dike.
Sources
- Zwin Natuur Park – homepage (hours, ringing dates)
- Zwin Natuur Park – tickets
- Zwin – Steltlopertrek volop bezig (wader passage, Sept)
- Zwin – satellite-tagged storks (colony in and around the park)
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