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

Frugivore guild
among consumers based on species partitioning is high in Sainte Luce, the different
frugivore species are not ecologically redundant due to their differential impact. Moreover,
the actual diet overlap may be lower than described here because proportional use of diet
items should be included (Poulsen et al. 2002). In terms of conservation E. f. collaris is of
crucial importance for the dispersal and regeneration of large seeded plant species, P.
rufus for long distance dispersal across fragment boundaries and frugivore bird species
for enhancing succession and regeneration of plants in degraded areas.
Although our dietary records for each consumer species are not exhaustive, it is
assumed that the interactions reported here are an unbiased sample and thus that the
patterns found provide an accurate picture of how interactions are organized in the littoral
forest on a species-specific as well as on a community level. On the one hand, speciesspecific
fruit choice is to a limited extent determined by a particular set of morphological,
biochemical, and phenological traits. However, on the other hand, there is substantial
dietary overlap among species. Unpredictable food availability in the littoral forest may
have led to this diet generalisation and to a species-poor frugivore guild as well.
However, each frugivore has its own particular impact in the seed dispersal of plant
species. As the littoral forests become more fragmented, the remaining patches become
increasingly isolated, and heterogeneous seed transport within and between forest
patches becomes more critical for long-term species survival.
ACKNOWLEDGEMENTS
We are very grateful to QMM (QIT Madagascar Minerals) for providing logistics and infrastructure at
the study site. In particular we thank Manon Vincelette, Jean-Baptiste Ramanamanjato, and
Laurent Randrihasipara of the QMM Environmental and Conservation Team. Special thanks go to
Giuseppe Donati, Nicoletta Baldi, and Valentina Morelli from the University of Pisa (Italy) for making
their data on fruit eating by Eulemur fulvus collaris available. This draft benefited greatly from
suggestions of Steve Goodman, for which many thanks. This study was carried out under a
Collaboration Agreement between the Department of Animal Biology and Department of
Anthropology of the University of Antananarivo and the Institute of Zoology of Hamburg University
and QMM. The first author is supported by a grant from the Belgian Fund for Scientific Research,
Flanders (FWO). We thank the Flemish Government for structural support to the CRC of the RSZA.
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