Winter migratory birds: You can see them roughly from the last ten days of October to the first ten days of March.

They appear around April and live and breed until September, before migrating to southern regions in the autumn.

Around April to May and from around the last ten days of August until October, when they migrate to their breeding grounds and wintering place, they feed while resting at the mouth of the Nakdonggang River, storing energy in preparation for the long flight ahead. The birds of passage are mostly snipes and plovers and they form a group of more than, 2,000 birds in all, covering the sandy shore and mud flats.

Resident birds: These are birds which do not migrate according to the season but breed and spend the winter here, all within a certain region.

Their bodies are soft and they have arthromeres. All molluscs are active with soft muscular feet. These include clams or gastropods, which are a common sight.

Their bodies are bilaterally symmetrical and they have a constitutional structure with a dermoskeleton made of a chitinous substance on the surface of the body. They include prawns or crabs, which are both common

In addition to the molluscs and arthropods, a lot of zoobenthoes such as lugworms, gray mullet and javeline goby inhabit the mud flats at the mouth of the river.