Gardens’ Bulletin Singapore 70 (Suppl. 1): 191-217. 2018 
doi: 10.26492/gbs70(suppl.l).2018-10 
191 
Conservation outputs and recommendations for Nee Soon 
freshwater swamp forest, Singapore 
Y. Cai 1 , G.W.H. Davison 1 , L. Chan 12 & S.Y. Liong 3 
‘National Biodiversity Centre, National Parks Board, 
1 Cluny Road, 259569 Singapore 
cai_yixiong@nparks.gov.sg 
international Biodiversity Conservation Division, National Parks Board, 
1 Cluny Road, 259569 Singapore 
3 Tropical Marine Science Institute, National University of Singapore, 
18 Kent Ridge Road, 119227 Singapore 
ABSTRACT. The current paper acts as a summary to the “Nee Soon Swamp Forest biodiversity 
and hydrology baseline studies project”, including results published previously and the results 
from papers of the current volume. Overall, flora and fauna surveys indicate healthy and 
diverse plant, fish and aquatic macro invertebrate communities in Nee Soon freshwater swamp 
forest. There are some concerns over terrestrial and aquatic alien invasive species, loss of big 
emergent trees, small population sizes and viability of various native species, and the uncertain 
outcomes of changes in water quality and quantity. The findings inform management that Nee 
Soon freshwater swamp forest is especially vulnerable to changes in hydrology and there is 
much dependency on precipitation for its water budget. Projected climate change effects on 
precipitation and statistical analyses of biotic responses to hydrology clearly define drought 
as a major, perhaps the foremost, source of vulnerability to the ecosystem functioning of Nee 
Soon freshwater swamp forest. Potential management solutions are suggested to address five 
issues of concern for the forest: hydrological integrity, erosion and sedimentation, ecological 
integrity, the impact of the spillway, and impacts of construction and development. 
Keywords . Biodiversity management, hydrological management, monitoring, wetlands 
Introduction 
Nee Soon constitutes Singapore’s last remaining patch of primary freshwater swamp 
forest. From the viewpoint of ecosystem diversity alone, this makes the conservation 
of the Nee Soon freshwater swamp forest a priority (Clews et al., 2018). The number 
of plant and animal taxa currently found nowhere else in Singapore but Nee Soon 
only emphasises its conservation value. Given that Nee Soon freshwater swamp forest 
houses a large proportion of Singapore’s overall flora and fauna, conservation of this 
habitat undoubtedly has larger-scale, positive effects for biodiversity conservation 
in Singapore as a whole (Ng & Lim, 1992; Turner et al., 1996), addressing the 
conservation of biodiversity from species to landscape scales. 
Owing to the nature of its ecosystem and drainage, the Nee Soon freshwater 
swamp forest is extremely sensitive to external disturbances (Ng & Lim, 1992). 
Furthermore, many of the species found here are highly specialised and, thus, 
