A multitude of ponds dot the Metropolis. Each of them is unique and home to a myriad of living beings that compete fiercely. Who are these beings? How do they live? How did they get there? This is what we propose to discover, from the snails of a few millimeters, through the crustaceans, to the larva of several centimeters of the largest dragonfly in France. Appointment: 14h30 – Allée des pêcheurs in Leers Duration: 2h Contact: Maison de l'eau, de la pêche et de la nature at 03 20 99 00 22