The purpose of its designation as a nature reserve is to preserve a lagoon-like cove (or bodden) in the Bay of Greifswald as one of the last regional quiet areas for resting water birds.

The Wreechener See also has areas undergoing natural silting up that support special communities and are breeding grounds for rare bird species.

The cove is linked to the Bay of Greifswald by a short narrow channel spanned by a wooden road bridge.

As the sea level rose during the Littorina Transgression, the area was flooded and was joined to the Rügischer Bodden.

Typical species are common reed, saltmarsh rush, sea aster, softstem bulrush, tule and water mint.

After they had disappeared in previous decades as a result of fertiliser discharge and subsequent loss of water quality, in recent years new colonies of these species have re-established themselves.