Southwest of the RN7 from Andranovory, the Réserve Spéciale de Beza-Mahafaly is better known as a scientific venture rather than a tourist destination, but travellers are welcome. The spiny and riverine forest here harbours four species of lemur (ring-tailed, white-footed and mouse lemur, as well as Verreaux's sifaka), four species of tenrec (including the large-eared tenrec), fossa, radiated tortoise and more than 100 bird species.
There are six circuits through the park, with the pick being:
* Circuit Ihazoara (4km, three hours) Natural botanical garden, canyons and good lemur viewing.
* Circuit Parcelle 1 (2km, two hours) Gallery forest, excellent lemur viewing, a riverside bird hide and the chance to see radiated tortoises.
* Circuit Parcelle 2 (12km, four hours) Spiny forest, diurnal lemurs and a sweeping viewpoint.
Visitors can pitch a tent near the scientific station and simple rooms may be available if not in use by the scientists, both for a small fee. To get here and around you'll need a 4WD (the reserve is 35km east of Betioky on rough tracks; the turn-off is signposted at the southern end of Betioky). You'll need to bring your own food and supplies.
You should also check the local security situation before heading out – the roads between Andranovory and Betioky and south of Betioky are considered unsafe after dark.