Participate in a City Nature Challenge (Bioblitz)

Overview

A Bioblitz is a fast-paced community science event where people work together to find and identify as many wild species as possible in a specific area. In the Netherlands, this is a massive national pastime, especially during the annual global City Nature Challenge and campus-wide biodiversity campaigns. By using your phone to log observations, you contribute directly to Waarneming.nl, the premier Dutch biodiversity database. It is a fantastic, hands-on way to explore local nature, whether you are scanning the canals of Utrecht, the parks of Amsterdam, or the green spaces of Leiden.

Step-by-step Plan

1. App Setup (15 minutes): Download the free "ObsIdentify" app (highly popular in the Netherlands and linked to Waarneming.nl) or the global "iNaturalist" app. Create a free account so your findings can be recorded under your name.
2. Pick a Patch of Wild (15 minutes): Choose your exploration zone. Great options include local parks, urban canal banks, green roofs, or nearby forests like the Amsterdamse Bos or the Abtswoudse Bos in Delft. Even urban pavement cracks can harbor fascinating wild mosses and small insects.
3. The Biodiversity Hunt (2 to 3 hours): Walk slowly and keep your eyes peeled. Take clear, close-up photos of wild plants, insects, birds, and fungi. Try to get multiple angles—such as the top and underside of a leaf—to help the app's identification engine.
4. Log and Identify (30 minutes): Upload your photos through the app. ObsIdentify uses advanced image recognition to instantly suggest the species name, which local Dutch experts will later verify.
5. Celebrate the Finds (30 minutes): Wrap up your session at a nearby local cafe. Sit down with a warm drink, scroll through your digital collection of discoveries, and see how your findings contribute to the region's overall biodiversity map.

What to Bring

• Smartphone with a fully charged battery
• A portable power bank (photo-taking and GPS tracking can drain your battery quickly)
• The ObsIdentify or iNaturalist app installed
• Weather-appropriate clothing (a reliable wind- and rainproof jacket is essential for Dutch weather)
• Comfortable walking shoes
• Optional: A clip-on macro lens for your phone to capture high-quality close-ups of tiny insects or mosses

Budget

• App download: €0 (completely free)
• Park entry: €0 (almost all public parks and urban nature zones in the Netherlands are free to access)
• Optional post-hunt refreshments: €4 – €8 for a coffee and a slice of Dutch apple pie (appeltaart)

Tips & Accessibility

• Keep it Wild: Cultivated garden plants, agricultural crops, farm animals, and household pets do not count for a Bioblitz. The goal is to document wild flora and fauna reclaiming or thriving in human spaces.
• No Connection, No Problem: If you are exploring an area with weak mobile reception, simply take photos with your standard phone camera and upload them to the app once you are back on Wi-Fi.
• Accessibility: This activity is incredibly flexible and inclusive. You do not need to walk miles into the wilderness; a paved, wheelchair-accessible city park or even a backyard balcony is perfect for finding urban biodiversity. No prior scientific training is needed.

Backup Plan

If the classic Dutch rain sets in, take the search sheltered or indoors. You can conduct a "micro-bioblitz" looking for spiders, cellar slugs, and house moths on a covered porch, or pivot to visiting an indoor botanical greenhouse (like the Hortus Botanicus in Amsterdam or Leiden) or a nature-themed museum (such as Naturalis Biodiversity Center in Leiden) to appreciate biodiversity out of the rain.