We disagree with Mr Heng Cho Choon's view on the insignificance of Bukit Brown's biodiversity ("Bukit Brown not worthy of World Heritage status"; last Saturday).
Since being de-gazetted as a cemetery, Bukit Brown has become forested with many forest plants, like the terentang and the giant mahang colonising it.
We have been monitoring its wildlife for many years.
Yes, or biodiversity, it is not comparable to Bukit Timah Nature Reserve, Pulau Ubin or Sungei Buloh.
But if it is in terms of the occurrence of rare or nationally threatened species, our records at Bukit Brown show 15 bird species listed on The Singapore Red Data Book, including critically endangered species like the white-bellied woodpecker, white-rumped shama, spotted wood owl, grey-headed fish eagle and black-headed bulbul.
There is a new butterfly record for Singapore, the banded line blue, as well as a rare one, the golden royal.
There is also an unconfirmed report of the Sunda pangolin, a critically endangered mammal, both globally and nationally.
For plants, you have the endangered Hoya latifolia and several species listed in the Singapore Red Data Book as vulnerable.
The biodiversity importance of Bukit Brown has more to do with its proximity to the MacRitchie forest, just across Lornie Road.
The presence of many forest species in Bukit Brown makes this area very important as an extended feeding ground/habitat for forest species whose populations have probably exceeded the carrying capacity of the MacRitchie forest, which is isolated from the main portion of the nature reserves by a golf course, reservoir and dam.
An example is the sighting of a Malayan colugo (flying lemur) at the very edge of the Bukit Brown forest contiguous to Lornie Road. This fascinating forest mammal must be desperate enough to risk gliding across a seven-lane road to reach the nearest tree across it.
Bukit Brown also serves as an indispensable stepping stone for the dispersal of wildlife to nature areas southwards, such as Malcolm Park and Botanic Gardens, as the animals search for habitats beyond MacRitchie.
For these reasons, we have proposed to the authorities that Bukit Brown be made into a cultural-cum-natural heritage park.
Ho Hua Chew (Dr) Vice-Chairman Conservation Committee Nature Society (Singapore)