Aride is the northernmost island of the granitic Seychelles. It covers an area of roughly 68 ha (approximately 0.67 km²), being 1.6 km long and 0.6 km wide. Alongside Aldabra, Aride hosts one of the most important seabird populations in the Indian Ocean. Eighteen species of native birds (including five only found in Seychelles) breed on Aride; this is far more than on any other granitic island. The island is leased and managed as a nature reserve by the Island Conservation Society of Seychelles but is presently owned by the Island Conservation Society-UK (ICS-UK), a UK based charity. The only human inhabitants are the reserve's staff, currently four Seychellois rangers and two island Wardens. They live in small plantation houses close to the beautiful coral sand beach overhung by palms on the south side of the island.

The bulk of the island is granite rock, forming steep cliffs on the north side and rising to almost 142 m at the highest point. This vantage point allows magnificent views of Greater and Lesser Frigatebirds soaring at eye level. Aride is the only place in the granitic Seychelles where these birds can be so closely encountered, and is home to a roosting population over ten times the size of that on any other island in the granitic Seychelles.

Over 1.25 million seabirds regularly breed on Aride, including the world's largest colony of Lesser Noddies, the world’s only hilltop colony of Sooty Terns, and the Indian Ocean’s largest colony of Roseate Terns (named arideensis, after the island). The island is also home to the world’s largest colony of Audubon's Shearwaters, and what is thought to be the world’s largest colony of White-tailed Tropicbirds. There are also very large numbers of breeding Brown Noddies, Fairy Terns, Wedge-tailed Shearwaters and a few pairs of Red-tailed Tropicbirds - Aride is the only place in the granitic Seychelles where this species breeds, or indeed where you are likely to see it!

Co-operation with other conservation organisations has led to spectacularly successful translocations of several endangered or restricted-range endemic bird species. The Seychelles Warbler was introduced from Cousin Island (until recently the world's only known location for this species) to Aride in 1988. Aride now houses the world's largest population of the species. The Seychelles Fody was also introduced from Cousin in 2002, and the Seychelles Magpie Robin from Fregate, most recently in 2002. The Seychelles Blue Pigeon and the Seychelles Sunbird have re-colonised Aride naturally.

The island is largely covered in native woodland, including the endemic Wright's Gardenia (Rothmannia annae), a shrub with beautifully scented flowers that is found naturally nowhere else in the world. Also found on the island is a Peponium species (from the cucumber family) which is possibly another Aride endemic. The protection of coastal woodland, devastated on most other islands, is being encouraged on Aride. Mapou (Pisonia grandis) woodland is by far the best example of such habitat in Seychelles if not the Western Indian Ocean.

Aride has a particularly rich reptilian fauna that includes 3 species of skink (a type of lizard), 3 species of gecko (another type of lizard) and 3 species of harmless snake. In fact, Aride has the highest density of lizards in the world . Two species of marine turtle, Green and Hawksbill regularly nest on Aride’s beaches. The island is becoming an increasingly important breeding site for the Hawksbill in the Western Indian Ocean.

The reserve boundary extends 200 m offshore, thereby protecting a beautiful coral reef and its associated marine life (slowly recovering from bleaching caused by the 1997/8 sea-warming event). Over 400 species of fish, from Whale Sharks to Flying Fish have been recorded on the reefs surrounding Aride.