|Central coordinates||46o 31.00' East 15o 55.00' South|
|IBA criteria||A1, A2, A3, A4i|
|Altitude||0 - 25m|
|Year of IBA assessment||2001|
Site description The site lies 20 km from Mahajanga. Bombetoka Bay is delimited, in the north, by a line from Katsepy in the west to the headland just north of Boanamary in the east, and, in the south, by the Marovoay flood-plain. The bay consists of mangrove islets (c.43,500 ha) separated by channels (c.21,500 ha at high tide) and mudflats (c.8,500 ha at low tide), with shallow subtidal waters in the estuary. The water is shallow (less than 5 m deep at low tide), except towards the mouth, and is very turbid. Northern mangroves are relatively degraded (3–4 m high), while those toward the south are in better condition; likewise, those on the coast are more intact than those in brackish, inland areas, where the canopy is 6–8 m high. The largest mudflats lie immediately seaward of the mangrove islets. A muddy bar crosses the mouth of the estuary, c.10 m wide and covered with scattered mangroves. The Marovoay wetlands comprise a vast area of rice-fields, marshes with Cyperaceae, and a large reservoir, Lake Amboromalandy.
Key Biodiversity See Box and Tables 2 and 3 for key species. Sixty species are known from the site, of which 10 are endemic to Madagascar. The occurrence of a large, seasonal congregation of Anas bernieri (the largest known), and of several individuals of Threskiornis (aethiopicus) bernieri, in the Bombetoka estuary, is notable. The eastern part of Lake Amboromalandy is very rich in waterbirds.
Non-bird biodiversity: Sirenian: Dugong dugon (VU; present, according to local people).
|Species||Season||Period||Population estimate||Quality of estimate||IBA Criteria||IUCN Category|
|Madagascar Teal Anas bernieri||resident||1997-1998||85 individuals||-||A1, A2, A3, A4i||Endangered|
|Madagascar Grebe Tachybaptus pelzelnii||resident||1997-1998||present||-||A1||Vulnerable|
|Lesser Flamingo Phoeniconaias minor||non-breeding||1997-1998||present||-||A1||Near Threatened|
|Madagascar Heron Ardea humbloti||resident||1997-1998||present||-||A1, A2, A3||Endangered|
|Great White Egret Ardea alba||non-breeding||1997-1998||700 individuals||-||A4i||Least Concern|
|Egretta dimorpha||non-breeding||1997-1998||286 individuals||-||A4i||Not Recognised|
|Madagascar Fish-eagle Haliaeetus vociferoides||resident||1997-1998||present||-||A1, A2, A3||Critically Endangered|
|Land-use||Extent (% of site)|
|Notes: Collection of eggs and young of waterbirds.|
References Delacour (1932), Hawkins (1993a), Langrand (1987), Rabarisoa (1994), Rabarisoa et al. (1995), Ségalen (1956), Thorstrom and Rabarisoa (1995), Watson et al. (1993).
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Recommended citation BirdLife International (2015) Important Bird and Biodiversity Area factsheet: Bombetoka Bay and Marovoay wetlands. Downloaded from http://www.birdlife.org on 28/11/2015
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