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Location Madagascar, Mahajanga
Central coordinates 46o 55.00' East  15o 28.00' South
IBA criteria A1, A2, A3, A4i
Area 180,000 ha
Altitude 0 - 40m
Year of IBA assessment 2001

Asity Madagascar (Affiliate)

Site description This large bay is located 95 km north of Mahajanga. The bay is shallow and is generally less than 5 m deep at low tide, although the main drainage channel at its mouth is 20–90 m deep at low tide. Five rivers flow into the bay: the Sofia and the Tsiribihina rivers in the north-east, the Mahajamba river in the centre, and the Andranoboka and Masokoenja rivers in the south-east. There are 47,500 ha of mangroves, located at the mouths of the five rivers and dominated by Rhizophora and Avicennia. Those located along the sea are well developed (8–10 m high) and show no signs of exploitation. Tongue-shaped mudflats, c.750 m long and 500 m wide, occur along the edge of the mangroves. Some small rocky islets are present in the channel. Parts of the bay shore are rocky, and inland there are more or less wooded hills.

Key Biodiversity See Box and Tables 2 and 3 for key species. Thirteen species are known from the site, of which one is endemic to Madagascar. The site holds the largest congregation of Egretta dimorpha known.

Non-bird biodiversity: Lemur: Propithecus verreauxi coquereli (EN).

Populations of IBA trigger species

Species Season Period Population estimate Quality of estimate IBA Criteria IUCN Category
Madagascar Heron Ardea humbloti resident  1997  present  A1, A2, A3  Endangered 
Egretta dimorpha non-breeding  1997  447 individuals  A4i  Not Recognised 
Madagascar Fish-eagle Haliaeetus vociferoides resident  1997  present  A1, A2, A3  Critically Endangered 

Land use

Land-use Extent (% of site)
other -
Notes: Collection of eggs and young of waterbirds.

References Langrand (1987), Rabarisoa (1994), Rabarisoa et al. (1995), Ségalen (1956), Watson et al. (1993).

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Recommended citation  BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Mahajamba Bay - Anjavavy Complex. Downloaded from on 27/10/2016

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