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Statistical elucidation of acute faunal responses to hydrological events was not 
possible for this study based on overt surveying but warrants further investigation. 
For example, targeted studies should be aimed specifically at capturing rainfall events 
along with a high temporal resolution of faunal responses including passive and active 
drifting invertebrates (i.e. at scales over hours to days). 
iii) Future management 
Communication and cooperation among stakeholders should be enhanced by forming 
a working group or committee comprising all relevant stakeholders (ministries, 
statutory boards, academia, NGOs, public). Stakeholders should include any group 
with potential influence, impact and interest not just in Nee Soon freshwater swamp 
forest alone, but its watershed upstream and downstream. 
Reduction of the influence of the spill way/discharge from reservoirs would help 
to i) mitigate against changes in water quality; ii) reduce input of and local expansion 
in the distribution of less desirable (non-native) fish species within the swamp forest 
streams; and iii) maintain more “typical” forest stream communities of fish and 
invertebrates, notably the rarer taxa that are less prevalent elsewhere. 
To impede the spread of alien species into Nee Soon freshwater swamp forest, it 
may be possible to create a weir or low head dam downstream of Nee Soon freshwater 
swamp forest / upstream of reservoir input. However, this will probably bring about 
hydrological issues stemming from flooding or ponding upstream of such a weir or 
dam. An electric fish barrier (e.g. see http://www.smith-root.com/barriers/) could 
be created across the channel downstream of Nee Soon freshwater swamp forest / 
upstream of reservoir input, However, this would require funding, and would raise 
development, infrastructure, maintenance, long-term commitment; and safety issues. 
Environmental impact assessments (EIAs) would first have to be carried out 
to ensure that the faunal communities of Nee Soon freshwater swamp forest are not 
inadvertently impacted by the development and operation of any of these approaches. 
In addition, consultations with management of multiple agencies and other stakeholders 
will also be required prior to deployment of any engineering solutions (i.e. weirs, low 
head dam and electric fish barrier) to ensure minimal impact to ongoing operations 
(i.e. water transfer operations along spillways). 
Reduction of maximum water levels could be considered to avoid unnecessary 
disturbance of communities, by reduced input from the spillway, and by riparian and 
forest planting to reduce peak flows. Improvement of the current spillway and dam 
design, such as having a flap gate to prevent backflow of the reservoirs into the swamp, 
could also prevent peak flow disturbances to the Nee Soon freshwater swamp forest 
faunal communities. 
Maintenance of greater than minimum water levels in small streams could be 
considered, in particular to support the diversity of aquatic fauna found within the 
freshwater swamp forest, especially the rare taxa such as stoneflies that are generally 
not well supported in other catchments in Singapore. 
Although not explicitly investigated as part of this study, field observations of 
the main (3 rd order) stream channel suggest that the banks of the channel are eroding, 
and suspended sediment may be relatively high as well as the settling of sediments 
