This coastal park is located in the north-west corner of the country and extends from just outside the town of Barra to the northern border with Senegal, where it is contiguous with the Delta du Saloum National Park (IBA SN013). Ginak Island, included in the park, and separated from the mainland by the Niji Bolon channel, has some 15 km of narrow, sandy beaches facing the Atlantic, backed by sand-dunes. The island also has a small coastal lagoon, seasonally wet saltmarshes, narrow Rhizophora mangrove bordering the bolon, mudflats and rice-fields. The remainder of the island is degraded savanna woodland or arable. The dominant crop is Cannabis sativa. The mainland section of the park has more extensive, tall Rhizophora mangrove forest either side of the larger Massarinko Bolon and further small areas of saltmarsh and mudflats. There are two small villages in the park, both on Ginak Island.
See Box for key species. Of greatest importance are the tern and gull roosts which form on the Atlantic coast in the extreme north and south of the park, at Buniada Point and the mouth of Niji Bolon. Numbers are variable and may have recently declined with the shrinking of the sandbar at Buniada Point. The Atlantic coast is also notable for nationally high numbers of Sterna dougallii and, probably, several breeding pairs of the locally declining Charadrius marginatus. The tidal creeks, saltmarshes and rice-fields have generally low numbers of waterbirds, but Limosa limosa occasionally occurs in thousands. Large numbers of herons, egrets and terns regularly fly through the site into roosts in the Delta du Saloum National Park. Passerines are well studied, due to the activities of the Gambia Ringing Project, whose main interests are in the movements and site fidelity of wintering Palearctic passerines.
Non-bird biodiversity: Mammals of global conservation concern include Procolobus badius temminckii (EN) while Trichechus senegalensis (VU) may still occur. The turtle Chelonia mydas (EN) has been recorded and there is some evidence of breeding. Offshore, there is a small population of the dolphin Sousa teuszii (DD) which moves between Niumi and the Delta du Saloum.
BirdLife International (2019) Important Bird Areas factsheet: Niumi National Park. Downloaded from http://www.birdlife.org on 16/10/2019.