A number of species of (smaller) protected animals live in the Rotterdam port area, such as the natterjack toad and the sand lizard. Account is being taken of them in the further port expansion. Development in places where there are protected species is only possible after investigation of alternatives and when the loss of habitat is compensated for elsewhere.
The natterjack toad lives in river areas and dunes, and also in heathland and peaty soils. It has been observed in various places in the Rotterdam port area, particularly at the Maasvlakte. The size of the population is presumed to be around 100 to 150 animals in the entire area. The natterjack toad is a strictly protected species. The former Ministry of Agriculture, Nature and Food Quality granted the Port Authority exemption from the prohibition on disturbance of the natterjack toad. This was possible partly because the Port Authority had constructed toad pools. The natterjacks were moved to these pools so that they could continue to live undisturbed.
The sand lizard is a rare reptile species in the Netherlands. Its ideal habitat is bare sand with varied vegetation. The sand lizard has been observed in the Rotterdam port area on the seawall south of De Slufter. The sand lizard has been able to reach the Maasvlakte by independently crossing the Brielse Gat dam. It is not impossible that the species will spread further across the Maasvlakte. This would in fact take several years, due to the great distances. Moreover, the sand lizard takes badly to disturbance, due to which much of the Maasvlakte is not a suitable habitat.