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make way for the plantation agriculture during the British colonial period.
The plantation area grew from 19 km
2
to 2,500 km
2
within less than a
century without concerning the natural equilibrium of the watershed
(Wickramagamage 1990). The land value of forested land per acre was
signifi cantly lower (13-65 pounds sterling) compared to the value of areas
cleared for cultivation (100-500 pounds sterling). The consequences were
immediately visible in the form of landslides, heavy soil erosion, soil
fertility decline and reduction in crop yields siltation of low lying areas,
frequent fl ooding, drying out of streams, etc. During the British colonial
period Highlands of Sri Lanka were also used to provide for plantations
and roads, railway tracks, holiday homes, etc. There was not enough
concern about the ecological role of forests for water balance, soil fertility,
erosion prevention, and as habitat. British hunters killed exceedingly
large numbers of wild animals, which led to the threat of several species,
e.g., the Sri Lankan elephant. A single hunter reported that he alone had
killed more than 6,000 wild elephants (Baker 1853). The third stage of
invading the environmentally sensitive Central Highlands started after Sri
Lanka's independence in 1948. The multipurpose Mahaweli Development
program was part of this stage. The attention to ecosystem and biodiversity
conservation in the submerged areas and to the impact on dried up areas
was inadequate. According to the report An Environmental Evaluation
of the Accelerated Mahaweli Development Program, the current data on
wildlife population characteristics, migration and dispersal patterns, and
habitat requirements are not suffi cient to guide management decision
making. Habitat conditions in many of the designated protected areas
were degraded over time, and restoration or enrichment measures were
insuffi cient to support the existing wildlife populations. In addition to that
some environmental and cultural values were destroyed (Tolisano et al.
1993, IEG 2012, Bulankulama 1992). Before the Mahaweli project started
there were 257 bird species, 50 mammalian species, and more than 20
reptile species in addition to amphibians and some others. Most of them
are extinct now due to the destruction of lower lying areas of the evergreen
forest and riparian ecosystems (Tolisano et al. 1993). The inhabitants of the
Mahaweli project area were sheltered in newly developed areas, and given
a fi xed extent of land. During heavy rain periods, they were exposed to
diseases spread by mosquitoes. Increased population pressure lead to the
exploitation of remaining forest areas for shifting cultivation or for attaining
fi rewood (IEG 2012) and the day to day problems they face are created due
to substantial tension and stress (Tolisano et al. 1993, Furset 1994) (Fig. 15.6).
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