This site is situated in the southern half of Praslin and extends from sea-level in the south to the highest point on Praslin (367 m). It includes Praslin National Park (330 ha). Most of the hill-slopes of the site are covered by a secondary mixed forest with a high proportion of native species, mainly palms. This includes the magnificent palm forest of Vallée de Mai, dominated by the coco-de-mer Lodoicea maldivica (the famous female pelvis-shaped nuts of which are the biggest seeds of the plant kingdom), and all five of the other endemic palms of Seychelles, including Verschaffeltia splendida, Deckenia nobilis and Phoenicophorium borsigianum. Other notable endemics include Secamone schimperianus and Drypetes riseleyi. The Fond d’Azore and Fond d’Albaretz areas retain much endemic flora (Dillenia ferruginea, Northea hornei, Pandanus spp., etc.). A few forestry plantations of Swietenia macrophylla also occur. There are numerous small streams and waterfalls. The south-eastern part of the IBA contains drier areas with shrubs, boulders and caves. Fires have affected the site in the past. Much of the site is now no longer used for anything other than nature conservation, tourism being restricted mainly to the coast and the Vallée de Mai.
See Box and Table 2 for key species. This IBA is also of vital importance for Coracopsis (nigra) barklyi, as it represents its main breeding and feeding area. Restricted to Praslin and Curieuse, it is the national bird of Seychelles. The total Seychelles population is estimated to be between 200–300 birds (fewer than 100 pairs), of which 92–150 birds occur at this site, where its numbers are probably increasing. The IBA also contains the only nesting cave of Collocalia elaphra known on Praslin (60–80 pairs). Falco araea was reintroduced on Praslin in 1980, but is now extremely rare (1–3 pairs). Terpsiphone corvina, now restricted to La Digue, was still present in the northern edge of the IBA in 1985. Three other Seychelles endemics, Alectroenas pulcherrima (300–700 pairs), Hypsipetes crassirostris (250–500 pairs) and Nectarinia dussumieri (50–100 pairs), are common. Other species of interest include Streptopelia picturatapicturata while Phaethon lepturus and Gygis alba breed in very low densities. Butorides striatus and Gallinula chloropus (both residents) are present along the coast and Arenaria interpres, Numenius arquata and other visiting waders occur on the beaches all year-round.
Non-bird biodiversity: Amphibians and reptiles include one species of frog (Tachycnemis sechellensis) and six caecilians (e.g. Grandisonia spp.), four species of gecko (Phelsuma spp. and Ailuronyx spp.), two skinks (Mabuya sechellensis and Pamelascincus gardineri) and two snakes (Lycognathopis seychellensis and Lamprophis geometricus), all endemic to Seychelles. Sea-turtles Eretmochelys imbricata (CR) nest on the beaches and there is a feeding area for Chelonia mydas (EN) along the coast. The majority of the bat Pteropus seychellensis population of Praslin roosts in the IBA. Several invertebrates (e.g. molluscs) endemic to Praslin also occur.
Pressure/threats to key biodiversity
The Vallée de Mai (45 ha) was declared a nature reserve in 1966 to protect the coco-de-mer. It was declared a World Heritage site in 1983 and the Seychelles Island Foundation has been responsible for its management since 1989. Praslin National Park was declared in 1978. Long-term population monitoring and research is conducted on Coracopsis (nigra) barklyi and Collocalia elaphra by the Ministry of Environment and Transport. The Coco-de-mer palm population is also closely monitored. A project to erect 100 nest-boxes to protect Black Parrot nests from rat predation is currently being implemented. Main threats are fire and introduced fauna (Tyto alba, Rattus spp.) and flora. The cave hosting the swiftlet colony needs to be adequately protected. A management plan exists, but requires updating.