Global significance of freshwater swamp forest 
15 
Other adaptations include buttress roots, that provide stability in the unstable and soft 
substrates. Furthermore, many trees have lenticellate bark which aids in gas diffusion 
in anaerobic conditions (Whitten et al., 2000). Many of these root adaptations can be 
found in Southeast Asia’s freshwater swamp forests including those in Singapore. 
Aquatic fauna in freshwater swamp forests 
Previous work by Whitten et al. (2000) has documented that the fauna of freshwater 
swamp forests is as diverse as that found in lowland terra firma forests. However, 
research in this area is still very lacking (Goltenboth et al., 2006). Nonetheless, Posa et 
al. (2011) documented that approximately 23-32% of all species of mammals and birds 
in Peninsular Malaysia and Borneo have been recorded from peat swamp habitats. The 
proportions of snakes (7-18%) and amphibians (19-23%) are somewhat lower, but 
nevertheless, the results collated by Posa et al. (2011) do show that peat swamp forests 
provide habitats for a considerable proportion of the region’s fauna. 
Additionally, freshwater swamp forests support a number of rare, specialized 
and threatened species. Posa et al. (2011) found that 45% of mammals and 33% of birds 
recorded in freshwater swamp forests had an IUCN Red List status of near threatened, 
vulnerable or endangered. Additionally, Phillips (1998) documented the importance of 
swamp forests in conserving primates such as proboscis monkeys (Nasalis larvatus ) 
and the Bornean banded langur ( Presbytis chrysomelas). Previous work from Johnson 
et al. (2005) at Gunung Palung National Park in western Kalimantan, documented a 
higher density of Bornean orang-utan nests and individuals than in lowland forest. 
In addition, Cheyne et al. (2009) observed a number of endangered felids (e.g. the 
flat-headed cat, Prionailurus planiceps; the Sunda clouded leopard, Neofelis diardi; 
and the marbled cat, Pardofelis marmorata) within swamp forests, whilst Bezuijen et 
al. (2001) documented swamp forests to be favoured habitat for the endangered false 
gharial ( Tomistoma schlegelii). 
These results already suggest that freshwater swamp forests are extremely 
important for conservation, but it must also be remembered that there has been a 
general bias towards charismatic mammalian species in biodiversity research (Clark 
& May, 2002). Conversely, invertebrate, fish, amphibian and reptilian research has 
usually been under-represented (see Wells & Yule, 2008; Yule, 2010), despite the fact 
that these groups are often much more diverse than mammals, making up some of 
the dominant animal groups in the forest (Clark & May, 2002). Thus, the importance 
of freshwater swamp forests in preserving overall faunal diversity has in fact been 
understated thus far. 
Freshwater fish serve as a good example of the importance of freshwater swamp 
forests to less well known groups. They have been documented as exhibiting extremely 
high endemicity to swamp forests, up to the point that 33% of known freshwater 
fish species are associated with peat swamps (Ng et al., 1994; Kottelat et al., 2006). 
Additionally, Posa et al. (2011) found that out of 219 fish species collated from peat 
swamps, 80 species are restricted to this ecosystem, while 31 species are point endemic 
