One of the species living there is the lagoon cockle. This is a rare species in the Netherlands. In the Wadden Sea region outside the dikes, it is only known from the Slufter and from Schiermonnikoog island. In Zeeland province it occurs a bit more.
In the Kreek van Madura water in the Slufter, researchers found many lagoon cockles. Other animal species there: Hydrobia ventrosa snail; common prawn; shore crab; common goby; pill woodlouse; and sandworm.