Sand nourishment is an essential part of the long term flood defense strategy of the Dutch coast. A distinction can be made between beach nourishments and underwater nourishments. This report concerns underwater nourishments. Nourishments have ecological consequences that differ between species living in the shallow coastal zone. An additional complication is that the ecosystem in this shallow zone is not well studied because it is too shallow to use a ship, and too deep to walk. Hence, knowledge on abiotic and biotic conditions in which species live is scarce. However, some studies were done in the shallow zone and knowledge on the use of the shallow zone by fish is recently developed in the projects Zandmotor and Building with Nature HK3.8 Smart Nourishments.