Primates in Peril

Lac Alaotra Bamboo Lemur
Hapalemur alaotrensis Rumpler, 1975
Madagascar
(2000, 2014)
Fay Clark and Lance Woolaver
Hapalemur alaotrensis exclusively inhabits the dense
papyrus and reed beds surrounding Lac Alaotra,
Madagascar’s largest lake, located on the western edge
of the eastern rain forest region (Mutschler and Feistner
1995). The species occurs as two subpopulations, a
small fragmented one in the northern part of the lake
around the Belempona Peninsula and a larger one in
contiguous marshlands along the lake’s southwestern
shore. Its entire range appears to be less than 5,800
ha and it occurs only up to elevations of 750 m. The
lake is surrounded by a vast wetland area consisting of
14,000 ha of marshes and 175,000 ha of rice fields and
constitutes an important biodiversity area (Pidgeon
1996). Guillera-Arroita et al. (2010) reported that
difficulties in monitoring this species arise because the
wetland is difficult to survey. It can only be accessed via
canals cut by fishermen, resulting in limited transects
for monitoring, and visibility is typically restricted to a
few metres.
The Alaotra watershed is of international importance
under the Ramsar Convention of 2003. The government
of Madagascar also recognized the conservation value of
this area by classifying it as a Temporary New Protected
Area within national law N°381-2007/ MINENVEF/
MAEP in January 2007, which was given permanent
protection status in July 2015. In spite of this, the
human population in the Alaotra watershed has rapidly
increased in the last few decades, from 109,000 in
1960 to approximately 550,000 in 2003 (Pidgeon 1996;
PRD 2003). People heavily rely on rice cultivation and
fishing for their livelihoods (Andrianandrasana et al.
2005; Copsey et al. 2009a; Wallace et al. 2015), leading
to severe loss, degradation and fragmentation of the
Alaotran marshes as lemur habitat (Mutschler et al.
1995, 2005). Conversion of marsh habitat to rice fields
has been the most significant historical and continuing
threat to the survival of H. alaotrensis. From 2001-2007
there was a decrease in the coverage of marsh vegetation
of 29.7%, from 19,000 to 14,000 ha (Durrell unpublished
data). Marsh burning inhibits the regeneration of H.
alaotrensis habitat which also declined during that same
period from 9,400 to 5,800 ha. Unfortunately, marsh
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Lac Alaotra bamboo lemur (Hapalemur alaotrensis)
(Illustration: Stephen D. Nash)
burning increased dramatically in 2013 (3,000 ha)
and 2014 (2,600 ha) due to a lack of law enforcement
and an increase in coordinated pressure by people in
power organising conversion of the marsh to ricefields
for their own financial benefit (Ratsimbazafy et al.
2013). Some of this burned marsh will regenerate if
not converted to rice but the trend in annual burning
has accelerated. Hunting for food and capture for pets
has significantly reduced lemur numbers in the past
but has been mitigated somewhat in more recent years
due to intervention by conservation organizations
(Razafimananahaka et al. in prep). Various methods