of biodiversity when humans first settled in the area, including the disappearance of most of the giant tortoises from the granitic islands, the felling of coastal and mid-level forests, and the extinction of species such as the chestnut flanked white eye, the Seychelles parakeet, and the saltwater crocodile. However, extinctions were far fewer than on islands such as Mauritius or Hawaii, partly due to a shorter period of colonizer occupation. Seychelles today is known for success stories in protecting its flora and fauna. The rare Seychelles black parrot, the national bird of the country, is now protected. The freshwater crab genus Seychellum is endemic to the granitic Seychelles, and a further 26 species of crabs and five species of hermit crabs live on the islands. From the year 1500 until the mid-1800s (approximately), the then-previously unknown Aldabra giant tortoise was killed for food by pirates and sailors, driving their numbers to near-extinction levels. Today, a healthy yet fragile population of 150,000 tortoises live solely on the atoll of Aldabra, declared a UNESCO World Heritage Site. Additionally, these ancient reptiles can further be found in numerous zoos, botanical gardens, and private collections internationally. Their protection from poaching and smuggling is overseen by CITES, whilst captive breeding has greatly reduced the negative impact on the remaining wild populations. The granitic islands of Seychelles supports three extant species of Seychelles giant tortoise. Seychelles hosts some of the largest seabird colonies in the world, notably on the outer islands of Aldabra and Cosmoledo. In granitic Seychelles the largest colonies are on Aride Island including the world's largest numbers of two species. The sooty tern also breeds on the islands. Other common birds include cattle egret (Bubulcus ibis) and the fairy tern (Gygis alba). More than 1,000 species of fish have been recorded. The granitic islands of Seychelles are home to about 75 endemic plant species, with a further 25 or so species in the Aldabra group. Particularly well known is the coco de mer, a species of palm that grows only on the islands of Praslin and neighbouring Curieuse. Sometimes nicknamed the "love nut" (the shape of its "double" coconut resembles buttocks), the coco-de-mer produces the world's heaviest seed. The jellyfish tree is to be found in only a few locations on Mahé. This strange and ancient plant, in a genus of its own, Medusagyne seems to reproduce only in cultivation and not in