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Last Updated on 16.07.10
BIODIVERSITY
Danube Delta is a real paradise of fauna. Starting with 1991, there has been started a project to develop a nomenclature with all the flora and fauna species within Delta territory, action that continues even today.
It has two main objectives: to know the importance of the natural heritage components within a natural biosphere reserve and to emphasize the species that need protection and preservation measures.
98% procent of the European aquatic fauna can be found here, also the entire aquatic lepidoptera and European gastropod mollusc, and the refuge of rare mammals such as Mustela lutreola, Lutra lutra and Felis silvestris.
The diversity of the fauna is determined by the diversity of the habitats, especially due to the fact that more than half of the identified ecosystems are natural. There have been identified a number of 623 species, of which 99 are on the list of European norms. The invertebrate fauna is very rich, at the moment being identified over 3000 species, among which 435 species of warms and rotalian, 9 species of mollusks, 115 species of shell fish, 168 species of arachnida and 2.244 species of insects. Up to present, have been described 37 new species for science, including
Avifauna. Are represented by a number of 327 species, that use the territory for nesting, during the migration period or for wintertime, and that represent 80% of the Romanian avifauna. Among them are included international threatened species such as
Among these, 218 species nest, the rest of 109 species transit through the delta and stay for different periods of time in autumn, winter and spring. The aquatic birds are the most numerous ones: 81 species nest and 60 ones transit the delta, in total being 141 species.
Terrestrial fauna. There have been identified a number of 42 species of mammals including species of importance European preservation such as the otter (Lutra lutra) and the European mink (Lutreola lutreola). The common muskrat (Ondatra zibethicus) and the wild boar (Sus scrofa) have an economical importance for their fur and for the hunting. Other predators are represented by the ermine (Mustela erminea), raccoon dog (Nyctereutes procyonoides), fox (Vulpes vulpes) and the wild cat (Felis silvestris).
Aquatic fauna. The population of fish are represented by a number of 45 species among which the most known ones are the catfish (Silurus glanis), northen pike (Exos lucius), European pike perch (Stizostedion lucioperca), Black sea herring (Alosa pontica), carp (Cyprinus carpio) and the amphibians are represented by 2 caudate species and 6 anure species and 8 reptile species.
HABITATS
On the Danube territory were identified many types of habitats, such as willow, forests, natural eutrophic lakes, plopars and willows, marshes with Typha, bushes (pledge, willow), marshes with Phragmites, wetlands with meadows, dry meadows. Due to the fact that every year, the Danube Delta Bioshere Reserve undergoes periods of floods and periods of water withdrawals, the two types of ecosystems, terrestrial and aquatic, are interdependent, creating a specific Danube biome.
Among these types of ecosystemes there is no strict territorial and temporal delimitation, but periodical succesion and replacement. When the floods are big, the terrestrial ecosystem that used to be, is replaced by an aquatic one, and during the long droughts, the aquatic ecosystems are replaced by some terrestrial ones.
