The proposed Parc Regional de Belomotse - Frontier-publications ...

proved difficult to identify, as the measurements and external characteristics do not
resemble those of M. brevicaudata. This may be an undescribed species of Microgale,
or a previously undescribed regional variant of M. brevicaudata. Specimens and DNA
samples have been sent to Chicago Field Museum for analysis. Results are not yet
available. Until formal identification has been completed, the species has been
tentatively assigned as M. brevicaudata.
The Coquerel’s dwarf lemur, Mirza coquereli, is currently listed as vulnerable with a
decreasing population (IUCN, 2002). During this survey this species was frequently
observed, foraging high in the canopy in gallery forest. It was not observed in
degraded gallery forest with low or fragmented canopies, nor was it observed in spiny
forest. This indicates that the species is dependent on undisturbed riparian forest.
Furthermore, the species is solitary with large home range sizes (Sussman et al.,
1985), so large areas of continuous forest are necessary in order to sustain viable
populations. Comparatively little gallery forest is left in Madagascar, and the
remaining areas are highly fragmented. These factors are part of the reason for the
classification of M. coquereli as vulnerable. The unexpected existence of
comparatively large populations in the surveyed area is a positive sign and an
important find for the conservation of this species.
5.4.5 Threats to mammal conservation
A number of factors affect mammal species density and distribution throughout
Madagascar. Several of these factors impact severely on specific mammal species,
causing declines in their overall populations and threatening their survival.
Throughout Madagascar, large areas of land are being cleared for agriculture. In
addition, forested areas are cleared for the production of charcoal and the collection of
firewood and building materials. Some endemic mammal species, such as Microcebus
murinus, are distributed throughout a wide variety of habitats and adapt well to
changing environments. However, many endemic mammal species are sensitive to
change, so populations are often adversely affected by habitat degradation. Many
mammal species are limited to specific habitats and comparatively small areas in
Madagascar. Clearance and fragmentation of the habitats and areas can be reflected by
a decrease in the populations of these mammals, which can lead to species becoming
vulnerable or endangered with extinction.
The remaining areas of gallery forest within the region of the proposed Parc Regional
de Belomotse are under severe threat through clearance for cultivation and charcoal
production. The corridor of gallery forest between Antafoky Lake and the Sept Lacs
region is very fragmented and it is doubtful whether it can be classified as a corridor
for certain mammal species. The small populations of many species that have become
isolated by fragmentation of habitats may be in danger of local extinction. An
example of this would be the dwarf lemur, Mirza coquereli, which is sensitive to
habitat fragmentation. This species was only found in gallery forest and now appears
to form three fragmented populations; one around Lake Antafoky, a second in an area
of forest near to Mahaleotse and the last in the upper reaches of the Sept Lacs region.
Further degradation of these sites will limit the range of this species still further.
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