Singapore has an estimated 23,000–28,000 species of terrestrial organisms and 12,000–17,000 marine organisms, making up over 40,000 kinds of non-microbial organisms.

Some groups are more easily discernible, with very accurate species counts. We have recorded a total of more than 390 species of birds and at least 2,100 native vascular plants, of which more than 1,500 species are classified as extant in Singapore. In contrast, the diversity of life in freshwater and marine habitats is less, especially the smaller aquatic organisms, on the numbers of bacteria, fungi and single-celled organisms in Singapore.

Singapore’s native species were thriving even before the arrival of man or flourished after coming from elsewhere in the region under their own powers of dispersal. A continuing process, colonisation brings new species, either temporarily or permanently to Singapore.

Examples include the introduced or ‘alien’ species that are accidentally or deliberately brought in by humans such as exotic pets, food materials, soil, or escaped or released wildlife. These ‘aliens’ often compete with native species, and can cause significant damage while others can be benign or even beneficial. However, the effects are normally only realised many years later, making it too late to introduce any preventive measures.

Singapore is responsible for the conservation and good management of its native flora and fauna. This is especially true of our endemic species, which are unique to the country. Scientists and naturalists contribute sightings and other information that help to evaluate the status of animal species, which are featured in the Red Lists, indicating where conservation actions are needed to assist threatened and endangered wildlife.