Fruit-frugivore interactions in a Malagasy littoral forest - Universiteit ...

Conservation
latex, which are placed in Ficus or other fruiting trees by adolescent men. Tenrecs are
hunted with the aid of dogs at dusk. Hunting occurs mainly for food purposes but
occasionally the animals are traded regionally as well for pets and this in particular for
Eulemur fulvus collaris and Coracopsis spp. (Bollen pers.obs.).
Charcoal production is an important activity of the people living in the extreme
southern Androy. At the moment, charcoal pits are regularly found in Mandena and
Petriky but not yet in Sainte Luce. It is a very destructive practice. A strip of forest is
cleared, branches are stapled in a hole in the ground, covered by vegetation and then
burned for several days. Charcoal is used by numerous people as fuel and represents a
major income for the Antandroy. It can be expected that in the near future these activities
will move up north towards Sainte Luce as the forests of Mandena and Petriky get more
depleted.
Furthermore QMM represents another threat as mining activities will destroy a large
part (76%) of the littoral forest (Lewis Environmental Consultants 1992a). In Sainte Luce,
74% of the remaining forest will vanish (QMM 2001). In November 2001, QMM got
permission of the Malagasy government to start the mining. For the coming six year all
infrastructure is being prepared to begin extraction of ilmenite in 2009 in Mandena.
Petriky and Sainte Luce will be mined respectively 20 and 35 years later. Mining activities
will last 45 up to 60 years (Vincelette pers. comm.). Populations of numerous plant
species risk disappearing together with the fauna (Lewis Environmental Consultants
1992a). Anthropogenic pressure will then further intensify on the few remaining littoral
forest fragments outside the QMM concession zone.
As everywhere, population growth is associated with limited resources. Even though
the local people are responsible for most of the degradation and fragmentation of the
littoral forest at the moment, there is definitely also willingness from their part to protect
the forest. The President of Sainte Luce in 2000-2001, Olaf Abel Isaia has done this by
initiating a traditional dina. These are local agreements for protection of natural resources
(LOI N°96-025, 1996). At the moment, QMM and delegates from the three villages are
discussing on a new version of the dina for Sainte Luce, which will probably be finalised
later this year (Vincelette pers. comm.).
IMPACT ON ECOSYSTEM AND SEED DISPERSERS
Plant-frugivore interactions are important components of complex forest communities.
Vertebrate seed dispersal is a key process in the dynamics of natural vegetation and
vegetation recovery (Wallace and Painter 2002). Furthermore, frugivores play a vital role
in the maintenance of biodiversity in tropical forests, where they constitute a large
proportion of the vertebrate biomass (Fleming et al. 1987). In the same way zoochorous
tree species make up the bulk of the tropical flora (Howe and Smallwood 1982). Loss of
fruit-frugivore interactions may thus have profound consequences for conservation
(Corlett 1998).
Many animal species in Sainte Luce rely on fruit as an essential food resource and
conversely provide valuable dispersal services to many of these fruit bearing plants
(Bollen et al., Chapter 3)(Table 1). As forests become more fragmented the remaining
patches become increasingly isolated and less accessible for arboreal lemur species. As
a consequence gene flow and seed dispersal between patches becomes more critical for
long term survival of many plant species. On the other hand, if fragments get too small or
hunting increases, the long-term survival of animal species will not be guaranteed either
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