1. A wetland should be considered internationally important if it contains a representative, rare, or unique example of a natural or near-natural wetland type found within the appropriate biogeographic region.
The site covers the Iron Gate Dam Reservoir and the adjacent mountains (Almaj and Locva) , and it is defined by large rivers mouth, hills and depressions, small villages which created the conditions for natural and cvasinatural ecosystems, such as associations of ash and poplar, but also comprising communities with Trapa natans and Salvinia natans, the west part of the site being known also like a very good habitat for Marsilea quadrifolia, species endangered or vulnerable in Europe. Also the presence in large surfaces of Typha spp. and Phragmites spp. communities creates the conditions for breeding, feeding and nestling of bird species mentioned here.
2. A wetland should be considered internationally important if it supports vulnerable, endangered, or critically endangered species or threatened ecological communities.
The site includes many threatened and near threatened species from the IUCN Red List of Threatened Species 2008, also protected by the national law regarding the protected areas: otter – Lutra lutra (Near Threatened), ferruginous duck – Aythya nyroca (Near Threatened), corncrake – Crex crex (Near Threatened), imperial eagle – Aquila heliaca (Vulnerable), European pond terrapin – Emys orbicularis (Lower Risk/near threatened), Herman’s turtle-Testudo hermanni (Lower Risk/near threatened). Besides, many species of European concern inhabit and use this site. Species like pygmy cormorant – Phalacrocorax pygmaeus, european fire-bellied toad – Bombina bombina, common tree frog – Hyla arborea, northern crested newt – Triturus cristatus, asp – Aspius aspius, Balkan loach – Cobitis elongate, white-finned gudgeon – Gobia albipinnatus and streber – Aspro streber are mentioned like Least Concern in the IUCN Red List of Threatened Species.
3. A wetland should be considered internationally important if it supports populations of plant and/or animal species important for maintaining the biological diversity of a particular biogeographic region.
Main characteristics of Iron Gates Natural Park are: phytocenologic diversity, mosaic-like aspect of associations, frequent changes in vegetal layers, all these in close correlation with versants exposure, valleys corridors and presence of petrographic and lithologic abrupt outcrops. The ecological features allowed the conservation of some quaternary and pre-quaternary flora and fauna elements. The biogeographic ford role of Danube Narrow Path is obvious given the existence of intersecting migration corridors of flora and fauna elements, since late tertiary to this day.
The big number of the flora and fauna species found here underlined the necessity of the designation of the protected area like RAMSAR site.
4. A wetland should be considered internationally important if it supports plant and/or animal species at a critical stage in their life cycles, or provides refuge during adverse conditions.
A lot of bird species arrive here during migration: corncrake – Crex crex, Anser albifrons, Scolopax rusticola,nesting: Vanellus vanellus, Picus canus, Ixobrychus minutus, or for wintering: common snipe – Gallinago gallinago, great white egret – Egretta alba,
The mammals (European bear – Ursus arctos, Linx – Linx linx, common otter – Lutra lutra) find here an optimal environment for reproduction and protection against hunters, the site being surrounded by hunting areas.
5. A wetland should be considered internationally important if it regularly supports 20,000 or more waterbirds.
218 bird species, from the total of about 500 European bird species, inhabit the site, breeding, nesting, wintering or in migration. More than 20000 individuals has been counting each year.
6. A wetland should be considered internationally important if it supports a significant proportion of indigenous fish subspecies, species or families, life-history stages, species interactions and/or populations that are representative of wetland benefits and/or values and thereby contributes to global biological diversity.
The ichtyofauna of Iron Gates Natural Park area is very well represented by all the Danube basin species. 47 fish species, many of them mentioned in the IUCN Red List of Threatened Species or in EU Habitats Directive and Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention), inhabit water covered areas in the site.
7. A wetland should be considered internationally important if it is an important source of food for fishes, spawning ground, nursery and/or migration path on which fish stocks, either within the wetland or elsewhere, depend.
Within the Ramsar Site the special interest has the Iron Gates 1 Water Reservoir. According to studies conducted in the area, the reservoir is a true kindergarten for Acipenser ruthenus, a species that migrates upstream to lay the eggs.
For other fish species migrating into Danube at maturity, the similar situation exists all along the green corridor of Danube River, especially in the western part of the park (ASPA pools and swamps). These pools, swamps, tributaries gulfs and the Nera delta have important role for reproduction of many fish species, such as Umbra krameri, Barbus meridionalis, B. barbus, Cobitis taenia, C, elongata.
Unfortunately, there is no synchronization between the regulation of water levels in reservoir and fish spawning period, so it often happens that fish row remain on dry surface. Another problem is absence of synchronization between the fishing prohibition period and spawning period. This decimates the fish populations in the Iron Gates area.