The reefs in the sub-areas of Rønne Bank and Adler Ground comprise imposing boulder fields interspersed with sandy areas. This mosaic provides richly structured habitats with rich species diversity and thus an abundance of food for fish, marine mammals and seabirds. In Rønne Bank, the boulders are covered in blue mussels (Mytilus edulis) which are in turn inhabited by barnacles. In Adler Ground, the flatter rocky reefs at depths of up to 10 m are mostly overgrown with toothed wrack seaweed (Fucus serratus) and also sea lace (Chorda filum) and red algae (Furcellaria lumbricalis), offering hiding places for many fish and other small marine creatures. Recent studies have shown a strong decline in these algae due to ongoing eutrophication and rising water temperatures. The deeper reef areas in Adler Ground are overgrown with blue mussels, as in Rønne Bank. Through their fine gills, the blue mussels extract not just the oxygen vital for their survival, but also plankton organisms and floating material as food. They help improve water quality as a result.

Characteristic species on the sandbanks at depths of 20 m are the Baltic clam (Macoma balthica), the soft-shell clam (Mya arenaria), cockles and various rare crustaceans (Bathyporeia pilosa, Pontoporeia femorata and Saduria entomon). These are all characterised by the fact they can survive in the low salinity of the eastern German Baltic Sea.

The fish species found in the area include gobies, European eel pout (Zoarces viviparus), sprat (Sprattus sprattus), herring (Clupea harengus), flatfish and Atlantic cod (Gadus morhua).

Odra Bank is the central morphological structure in the Pomeranian Bay. It is presumably a dune complex that was flooded when sea levels rose at the end of the last ice age. Odra Bank is practically homogeneous and covered with light fine sand which in some places is enriched with a large proportion of shell. This large, almost macrophyte-free sandbank is unique in the German Baltic Sea region and is both an excellent and a representative example of the habitat type “sandbanks which are only slightly covered by sea water all the time”.

Only few species of bottom-dwelling invertebrates occur in the Pomeranian Bay. However, thanks to the favourable oxygen and food supplies, these can form surprisingly large populations and biomasses. Because bottom-contact fishing has for many years been prohibited in much of Odra Bank, the characteristic bottom-dwelling organisms demonstrate natural distribution patterns and population dynamics. As a result of this abundance of bottom-dwelling invertebrates, the area is of vast importance as a permanently available source of food for a large number of fish species.

Due to the shallow waters and the associated favourable supply of oxygen all year round, both Adler Ground and Odra Bank play a key role as a starting point for recolonisation of neighbouring, deeper areas with bottom-dwelling organisms. This comes into play when increasingly more frequent and wide-spread occurrence of oxygen depletion results in mass mortalities in deeper waters.

Thanks to its rich and diverse bottom-dwelling organisms, the Pomeranian Bay is of great importance as a spawning and rearing area for flatfish such as turbot, plaice and flounder. Inexperienced young fish can quickly bury themselves in the fine sediment using their wave-like fin strokes. Some species perfect their camouflage by adapting their pigmentation to the colour and structure of the surrounding substrate.

Odra Bank is also an important feeding and wintering habitat for the Baltic Sea lavaret or whitefish (Coregonus lavaretus) and the twait shad (Alosa fallax). And, based on historical sources, it is also seen as a key potential marine distribution and feeding area for the sturgeon (Acipenser oxyrinchus) reintroduced into the Oder/Odra river and its tributaries. Sturgeon and twait shad are anadromous migrating fish requiring special protection as species listed in Annex II of the Habitats Directive. Anadromous fish enter rivers only to spawn; the adult fish live in the sea.

The harbour porpoise (Phocoena phocoena) observed in Rønne Bank and Odra Bank belong to the highly endangered harbour porpoise population of the central Baltic Sea, which comprised just less than 500 individuals at the last count. They use Rønne Bank and Odra Bank as transit and wintering areas. Mother-calf pairs have also been observed. This stresses the importance of the area for both breeding and conservation of this critically endangered population. The permanently ice-free areas of the Pomeranian Bay are vital to the survival of the harbour porpoise, especially in cold winters. They then migrate from the northern, ice-covered regions of the Baltic Sea into the Pomeranian Bay.  In the summer, harbour porpoise from the Belt Sea population also enter the protected area.

Harbour porpoise have been shown to be extremely sensitive to underwater noise. As Odra Bank sees little shipping traffic, harbour porpoise benefit from one of the quietest marine areas in the German Baltic Sea. However, the construction of offshore wind farms in the vicinity of the protected area has led to an increase in shipping traffic in and around the NCA.

In addition to the harbour porpoise, the protected area is also of importance for the grey seal (Halichoerus grypus). The grey seal population in the German Baltic Sea has grown significantly in recent years, especially in the waters around the island of Rügen. The protected area is an important feeding and migration area for these seals.

The mussels on the reefs and sandbanks of Rønne Bank and Adler Ground provide an important source of food for marine ducks, and especially the long-tailed duck (Clangula hyemalis). Due to the low salinity, the mussels form only thin calcareous shells and in doing so provide a relatively convenient and energy-rich source of food for marine ducks.

Very large numbers of long-tailed ducks can be found in vast areas of the German Baltic Sea in winter and in spring. Germany thus has a special responsibility to protect this duck species. Their main migration into the German Baltic Sea takes place from the end of October to the beginning of December. The largest contiguous staging area for long-tailed ducks in winter (December to February) is the marine area of Adler Ground with its outstanding blue mussel beds extending all the way to the shallow grounds of Odra Bank. Up to 210,000 individuals stay in the protected area, representing an extremely large percentage of the wintering population in the German Baltic Sea. They use the favourable food conditions to replenish their fat reserves following their strenuous periods of breeding and migration. Their migration back home into the breeding areas begins in early February and reaches its peak at the end of April.

Studies conducted by international research teams show a dramatic decline in the number of long-tailed ducks in the West Siberian-North European population, from 4.1 million (1992/1993) to 1.5 million (2007 – 2009). At the time of writing, it is not known if this is the result of poor breeding success or of high mortality. More recently, there has been a slight increase in populations of long-tailed ducks in the German Baltic Sea, but their numbers remain significantly below earlier levels. Full recovery is made difficult by both ongoing and newly emerging pressures in their breeding, resting and wintering areas.

In the German Baltic Sea EEZ, black-throated and red-throated divers (Gavia arctica and Gavia stellata) have their most important wintering areas in the Pomeranian Bay, as does the red-necked grebe (Podiceps grisegena). As many as 10 percent of the northwest European population of Slavonian grebe (Podiceps auritus), long-tailed duck, common scoter (Melanitta nigra) and velvet scoter (Melanitta fusca) winter or rest in the Pomeranian Bay. In winter, common scoter are widely distributed in the German Baltic Sea (60,000 individuals stay in the protected area). In spring (March to May), as many as 210,000 common scoter concentrate on Odra Bank in the protected area. In summer (June to September), the Pomeranian Bay is of special importance as a moulting area for the common scoter. This is where several tens of thousands of specimens of this black beauty spend the sensitive period during which they are unable to fly. As to the velvet scoter, some 85,000 winter in the Pomeranian Bay and as many as 75,000 in spring. The moulting population of velvet scoter fluctuates considerably and sometimes amounts to as many as several hundred birds.

Many other key species of seabirds also use the protected area as resting and feeding areas at various times of the year. These include the white-billed diver (Gavia adamsii), the razorbill (Alca torda), the black guillemot (Cepphus grille), the common guillemot (Uria aalge), the little gull (Hydrocoleus minutus) and the common gull (Larus canus).