Anjajavy Forest is an element of the Madagascar dry deciduous forests situated on the Indian Ocean of northwest Madagascar. The Anjajavy Forest surrounds the village of Anjajavy and provides the habitat for many rare and endangered species. This forest consists of roughly 50 square kilometres and occupies a continuous zone of much of the land peninsula upon which Anjajavy village lies. The peninsula is bounded by Majajamba Bay to the south and Narinda Bay to the north. Anjajavy Forest has much in common with other dry deciduous forests rising out of the tsingy limestone formations of western Madagascar. It is due to the presence of expansive tsingy outcrops as well as the remoteness of this part of Madagascar from the population center of the country at Antananarivo that the forest here has been less disturbed than many other forests in the country. For example, the central highland plateau, readily accessible from the population center, has been decimated by decades of slash-and-burn farming by indigenous peoples, leading to massive desertification and erosion. The incidence of species endemism in the western dry forests is very high, including ten of the fourteen known lemur genera, five of the eight tenrec genera and 16 of the 17 Chiroptera genera of Madagascar represented. There are a variety of mammals, birds, reptiles and arthropods present within the Anjajavy Forest.
Like most of Madagascar's dry deciduous forests, the upper canopy is composed of trees which shed their leaves in the winter months (June through September), including at least two species of baobabs endemic to the western part of the island. Trees here have adapted to the warm arid climate by shedding leaves in the dry season to reduce evapotranspiration, and some species such as the baobab store large amounts of water in their bulbous trunks.
There is a very high rate of species endemicity in all the western dry deciduous forests of Madagascar, for both flora and fauna; this rate is thought to be higher than for the eastern rainforests, although the biodiversity, while extremely high, is slightly less than the eastern counterparts. Geologically the tsingy formations have numerous subterranean caverns (used by early tribesmen) and karst formations, which provide underground water storage.
The forest canopy contains numerous species of deciduous trees, including at least two species of baobab, Adansonia rubrostipa and Adansonia madagascariensis. In addition, trees such as Grewia ciclea (Malagasy name, andilambarika) and Terminalia catappa (Malagasy name: antafana) occur. The latter tree provides a favourite food supply to the Coquerel's Lemur, with both fruits and leaves being appealing.
Some of the common shrubs found in the Anjajavy forest are Vepris ampody (Malagasy name: ampoly) and Rhizorphora mucronata (Malagasy name: honkovavy). There are also abundant lianas (vines) as well as numerous herbs, including the Madagascar vanilla (Vanilla madagascariensis, whose Malagasy name is vahimatso).
Lemurs are a noted species in the Anjajavy Forest, since they are abundant in the trees and even sometimes on the forest floor. The most frequently seen diurnal species are Coquerel's Sifaka and the common brown lemur. Other lemurs of the Anjajavy Forest are the Milne-Edwards sportive lemur (Lepilemur edwardsi) and the Pale fork-marked lemur.
The tsingy caves provide special habitat for the bats of this region, offering cool shelter. Probably the most common member of the chiroptera family locally is the Commerson's leaf-nosed bat (Hipposideros commersoni). The cave explorer will sight many bats in flight and some hanging from the ceiling on stalactite formations of the limestone cave interiors.
Also thought to be present in the Anjajavy Forest area is the endangered (EN – C2a classification per Redlist) Fossa (Cryptoprocta ferox), the largest mammalian carnivore in Madagascar. The nocturnal Greater hedgehog tenrec (Setifer setosus} also occurs in the forest here.
There is abundandant birdlife present in the Anjajavy Forest. One of the most notable is the Madagascar Fish Eagle (Haliaeetus vociferoides), which has four breeding pairs in the Anjajavy Forest according to Garbutt and Hogan. This very large bird of prey is endemic to western Madagascar, and the species is critically endangered, with an estimated 99 breeding pairs estimated in total existence. Other raptors present in the forest are the Madagascar harrier hawk and the Madagascar cuckoo falcon.
Some of the other bird species frequenting the Anjajavy Forest are the Helmeted guinea fowl, White throated rail, Glossy ibis, Madagascar White Ibis, Greater flamingo Broad-billed roller, Madagascar wagtail, Madagascar bulbul, Madagascar hoopoe, White-headed vanga, Crested drongo and the Pied crow.
An assortment of chameleons, lizards and snakes occur in the Anjajavy Forest. Among these are the Collared iguanid lizard (opluris cuveri) and the Lined plated lizard (Zonosaurus laticaudatus). Local snakes include the Madagascar ground boa (Acratophis madagascariensis) and the Madagascar hog-nosed snake (Leioheterodon madagascariensis). Chameleon species present include Oustalet's chameleon (Furcifer oustaleti) and the Jewel chameleon (Furcifer lateralis).