[2] The park lies within the Aegean and Western Turkey sclerophyllous and mixed forests ecoregion[3] and is situated on one of the main migratory routes for birds in Europe.

Glassworts cover large parts of the lagoons, forming little islands; common reeds and bulrushes create reedbed habitats; European alders, elms, willows and other trees are part of a forest that protects riverbanks from erosion; and common purslanes, petty spurges and many more plants thrive at the sand dunes of the park.

[7] In the Axios Delta National Park has been recorded an astonishing number of 299 bird species,[7] giving it worldwide ornithological importance.

[8] Some of these birds are the Dalmatian pelican, the greater flamingo, the collared pratincole, the Mediterranean gull, the pygmy cormorant, the Kentish plover, the glossy ibis and the squacco heron.

[15] Many invertebrates are found in the Axios Delta National Park, like butterflies, bivalves, beetles, gastropods and dragonflies of numerous species.

[16][17] Along the coastal zone of the Axios Delta National Park, 30,000 tons of mussels of the Mytilus galloprovincialis species are produced each year.

That is 80-90% of all mussels produced in Greece and the reason is that the Axios, Haliacmon and Loudias rivers are releasing nutrients in the water resulting in faster growth.

[21] Greek buffaloes date back 2,500 years ago and were brought to the country when Xerxes used them to carry his army's supplies across the struma river during the Greco-Persian Wars.