(HCVF) Toolkit for Malaysia - HCV Resource Network

5) What is the long-term viability of the local populations of these species?
When you have carried out surveys of the key endangered species in your FMU you will have quantitative
data that can be used to estimate their abundance in your FMU. As a rule, to prevent genetic inbreeding,
at least 50 breeding animals are needed to make up a viable population. The space needed by 50
breeding mice is very different from that of 50 breeding tigers. As a guide, larger animals generally require
much larger areas of forest over which to roam (see Figure 2 below). However, it is recognised that
population boundaries will seldom co-incide with FMU boundaries (with the FMU containing more than
one population of many species and only part of a population of some species).
Figure 2. Home range size of selected tropical forest animals plotted as a function of body weight
(adapted from Marcot et al., 2001).
6) What area of the FMU influences the maintenance/restoration of this animal?
A knowledge of the ecology of endangered species is needed to ascertain particular locations within an
FMU which are critical for the survival of species. Using GIS, you can then overlay a logging plan on the
wildlife base layer and see if there are areas of impending conflict, such as logging operations or roads
that will be built too near to or may destroy important sites for wildlife (such as the planned creation of
a log-landing area at a breeding site). Generally, the conservation of endangered species of mammals
14
(such as orangutans) can be aided by conserving certain “keystone” species of tree (such as figs ).
Depending on the scale of the FMU, at least 10% of the total area is recommended for strict protection
(Blockhus et al, 1992; Bennett & Gumal, 2001). The following patch sizes refer to the minimum area
of undisturbed primary forest to be retained as refugia, assuming it is within a larger area (at least one
logging compartment) of managed/logged forest.
14 As a generic conservation strategy, emphasis should be put on retaining figs (Ficus spp.) within the species mix for
enrichment planting.