The Văcărești ”delta” area is characterized as a bottom of a stuned lake, left behind after unfinished work on the transformation of this natural wetland in a dam lake. Văcărești wetland, which is part of the Dâmbovița meadow, has always been an area of high natural biodiversity. Unfortunately, the landscaping works caried out in the late 1980s have destroyed much of this natural diversity. Since the construction stopped, the area began to recover naturally and this process continues after 30 years. The series of small ponds from the concrete tub shelter a strange mixture of native and invasive fish species that have survived or were brought by humans or natural conditions. The fish population is rich, heterogenous, constantly evolving, represented by a strange mixture of indigenous species (pike, Crucian crap, perch, roach, rudd) and alien species (Prussian crap, brown bullhead, Mosquito-fish, common sunfish). From time to time there are also exotic species, released by aquarists, which survive only until the coming of winter. This ecosystem has been heavily influenced by the impact and anthropogenic influence so that it is presently in an „exotic” structure with a mosaic of native species that survived the human intrusion or naturally recolonized the area that coexists with various allogenous species introduced directly or accidentally by humans.