This site consists of a strip of mangrove located along the western coast and stretching over 90 km between Antsatsaka (25 km north of Ambanja) in the south, and Bobasakoa (45 km north-west of Ambilobe) in the north. Ambaro Bay lies off its southern part. Ampasinantenina (Port Saint Louis) peninsula divides the site into two parts, where the city of Antsohimbondrona is directly linked to Ambilobe by a tar road 30 km long. In addition to the mangrove, this site includes mudflats (1 km wide at low tide), lakes and saltmarshes. The main rivers in the area, the Bobasakoa, Andranomandevy, Mananjeba, Mahavavy, Itasy and Ambazoana, flow from north to south into the Mozambique Channel. Several of them (some nutrient-poor) rise from the underground waters of the Ankarana massif. The mangrove woodland is mainly composed of Avicennia and Rhizophora trees (5–10 m high).
See Box and Tables 2 and 3 for key species. Forty-eight species are known from the site, of which seven are endemic to Madagascar. The site supports the largest congregations of Dromas ardeola and Sterna saundersi known in Madagascar.
Pressure/threats to key biodiversity
This mangrove woodland is threatened by intensive cutting in some areas, and breeding-bird colonies are affected by the collection of eggs and young birds.