http://www.naturetrek.co.uk/   In the latest episode of BBC 1's Life in Cold Blood, viewers see Sir David Attenborough in Madagascar, fulfilling his lifetime ambition to find the world's smallest chameleon, the Pygmy Leaf Chameleon, a reptile no bigger than a thumbnail, that has eluded him for around half a century.

With over 50% of the planet's chameleon population present in Madagascar, natural history specialist Naturetrek hopes to observe at least some of the species during its 17-day holiday to the northern rainforests. However, despite many wonderful wildlife distractions, Naturetrek's main focus will be the island's endemic Lemurs, in particular, the world's largest nocturnal primate, the bizarre Gollum-like Aye-Aye. Tour departs London 1st November 08.

From Antananarivo, guests are transferred via Maroantsetra, to the lush rainforests of the Masoala Peninsula. The Masoala National Park is the island's largest rainforest reserve and a strikingly beautiful place dominated by huge trees draped in climbers, mosses and other epiphytes. It is thought to be the richest area in the country for wildlife - with much of this enormous biodiversity still largely unknown to science.

However, species to keep watch for include the more familiar lemurs - Red-ruffed and Whitefronted Brown Lemur - and bird species such as Red-breasted Coua, Short-legged Ground Roller, the bizarre Helmet Vanga and the rare and elusive Madagascar Serpent Eagle.

This will also be the first opportunity to look for the Aye-aye. No creature epitomises Madagascar's weird and wonderful wildlife more than the bizarre Aye-Aye, the scruffy looking bug-eyed lemur, with its trademark skeletal middle finger.

Visitors travel  across the Bay of Antongil to the island of Nosy Mangabe, where two nights are spent at the Nosy Mangabe Special Reserve - established to protect the Aye-aye.

The animals have since flourished and the island is now one of only two places where this bizarre and elusive lemur can be reliably seen in the wild. The reserve is also home to the Pygmy Leaf Chameleon.

Next up, the green oasis of the Montagne d'Ambre National Park in search of Sanford's Brown Lemur, Mountain Forkmarked Lemur and perhaps even the elusive Fossa. Bird species here are especially abundant and include the endemic Amber Mountain Rock Thrush, as well as Madagascar Ibis, Souimanga Sunbird and Pitta-like Ground Roller. Continue south, to the dry forests of Ankarana Special Reserve.

Here, the dramatic limestone landscape of Ankarana massif rises abruptly from the surrounding grassy plains, home to Crowned Lemur, Sandford's Brown Lemur and bird life such as Madagascar Pygmy Kingfisher and the localised Whitebreasted Mesite. The holiday concludes on the beautiful coral-fringed island of Nosy Komba, with time to relax on the beach, snorkel in crystal waters and dive on nearby reefs.