The site comprises the massif in the north-west of Mayotte, dominated by the peak of Hachiroungou (496 m). Ridges extend north, east and south, forming the watershed of the Dzoumonyé catchment. This area includes the upper slopes (over 180 m above sea-level) of Hachiroungou, the southern and eastern ridge, and the valley between these. The northern ridge (towards Mlima Dziani Bolé, 472 m) is excluded as it is deforested. The nearest towns are Dzoumonyé to the east and Acoua and Mtsamboro to the west. The slopes of Hachiroungou rise steeply to a triangular summit, and the slopes of the still partly forested Mapouéra valley are also fairly steep and dissected with streams. Hachiroungou supports a small expanse of mixed montane forest surrounded by cultivation and padza.
See Box and Table 2 for key species. The entire community of forest-living birds of Mayotte (around 14 species) is found at this site. Populations are likely to be small, in line with the area of forest remaining. Most species are common and not restricted to forest, although Dicrurus waldenii is found only in forest and forest-edge and the two pigeons are forest-dependent. Additional species occur in the cultivated land and villages around the forested area.
Non-bird biodiversity: Reptiles: Phelsuma geckos P. robertmertensii, P. nigristriata and P. pasteuri. No other data specific to this site.
BirdLife International (2019) Important Bird Areas factsheet: Crêtes du Nord Forest Reserve. Downloaded from http://www.birdlife.org on 21/04/2019.