SINGAPORE - Singapore will be conducting a year-long survey of the Bukit Timah Nature Reserve's animals and plants starting from March, and the results will be published in March 2017.

The comprehensive effort is timely as the last time the reserve was surveyed on a similar scale was almost 20 years ago, between 1993 and 1997, said the National Parks Board (NParks) on Saturday.

"The findings will provide us with a sound basis for the systematic long-term monitoring and management of the reserve, and help us ensure a sustainable nature reserve for future generations to enjoy," said Minister of State for National Development Desmond Lee at an event.

The survey will include NParks staff, scientists from academic institutions and people with expertise in some of the wildlife. It will focus on key groups of animals and plants that are crucial to the rainforest ecosystem, such as mammals, reptiles, butterflies, fishes, spiders, birds, amphibians, dragonflies and aquatic invertebrates. The work will also include the reserve's primary forest, which includes one of the largest forest patches in Singapore that has never been cleared by people.

Researchers and experts who were involved in the 1993-1997 survey will also be roped in. They include Mr Khew Sin Khoon, an architect who is an avid butterfly enthusiast and photographer. He is also author of the book, Field Guide To The Butterflies Of Singapore.

The reserve has at least 40 per cent of Singapore's native flora despite occupying only 0.2 per cent of its land. It is home to more than 840 species of flowering plants and more than 500 species of animals, including the rare and native ones like the Singapore Freshwater Crab.

On Saturday, MND's Mr Lee also launched a new coffee table book, Rainforest in a City, which was written by NParks volunteer Dr Chua Ee Kiam and published by the agency. Mr Lee also planted a tree as part of reforestation efforts at the new Windsor Nature Park, will be opened in 2016.