Open Day programme

On Saturday 3 October 2026, NIOO will open its doors again to visitors for our Big Open Day. From 11:00 to 17:00, everyone will be welcome. Seize your chance to take a look in our labs and experimental gardens: only possible once in every three years!
Landing page

Activity overview

We love to share what ecology is, why it is important and what we are studying exactly. And we will not only do that by talking, but also by involving visitors in stories, games and experiments.

Practical information about the Open Day
Open Dag

Filter the pond clean

The ‘Water Report’ shows that the water quality in the pond leaves a lot to be desired for our research institute. We need your eco-friendly muscle power to filter our water clean. Come and lend us a hand (or a foot) and find out how it works...

Filter de vijver schoon!

Insect memory under the microscope

In this game, you can choose from 11 different cards. Each card features a different insect, along with clues about its powers and characteristics. Can you spot that insect species under the microscope?

Microscopisch insectenmemory

Geese & GPS

Discover the hidden lives of geese with the help of modern technology. Learn how scientists use AI to recognise and count brant geese in large flocks, track barnacle geese with GPS transmitters during their daily flights and annual migrations, and find out which transmitters researchers can use to discover where geese travel to.

Ganzen GPS

Live Science bird ringing

Come and join us at the Ringing Table, where professional bird ringers will be demonstrating today how to ‘ring’ wild birds. A small, lightweight metal ring acts as a bird’s passport, bearing its own unique code. Can you decipher the code from a distance?

Live Science vogelringen

Solve the tulip mystery

Plants and micro-organisms can be the best of friends, each other’s worst enemies, or anything in between. But can you work out who does what? Take a close look at Dutch tulips with their spectacular colour patterns. Which microbes are behind them? Do they help the plant, or do they actually make it sick? Put on your detective’s hat and see if you can solve the mystery...

Los het tulpenmysterie op!

Step into the microworld

Micro-organisms are everywhere: in the soil, in plants, in water and in unexpected places all over the world. Come and meet some of our favourite microbes, find out more about our research up close on the Galápagos Islands, and, of course, take your own microbe selfie!

Stap in de wereld van microben

The breath of the lake

Even lakes ‘breathe’ – though not quite in the literal sense… Their ‘breathing’ of methane is caused by microorganisms. Come and visit us to discover how they protect our air from methane, see the equipment we use to study them, and find out whether you breathe out methane yourself!

De adem van het meer

Catch the water monsters!

Can you find any water monsters (or, in other words, aquatic animals) in our pond? And if so, which ones? Grab a landing net and then take a closer look at your monster under a microscope. You can then use an identification chart to find out which water creature you’ve caught. This activity will take place under the guidance of the Dutch Water Museum in NIOO’s experimental ponds.

Watermonsters gezocht!