Abstract:
BACKGROUND : Maputo Special Reserve (MSR) in Mozambique lays within the Maputaland
Centre of Endemism (MCE) and protects the biota of a habitat mosaic
dominated by coastal dune forest and inland sand forest patches of different sizes
surrounded by natural grassland.
OBJECTIVES : To determine the importance of woody versus grassland vegetation
for supporting endemic east coast versus widespread savanna dung beetles in the
MCE in the face of increased accessibility and exploitation of woody vegetation
in southern Mozambique, especially by charcoal burners.
METHOD : We used general linear mixed models, additive partitioning of diversity
and ordination to analyse species abundance and occurrence across a mosaic of
three major habitats in the MSR (grassland, sand and dune forest).
RESULTS : High compositional heterogeneity was found between habitat types and
study sites so that beta diversity was mostly higher than alpha diversity. Three distinct
scarabaeine dung beetle assemblages defined from ordination were largely
centred on the three habitat types. Out of a total of 61 species, greater numbers
were associated with grassland (38) than sand (17) and dune forest (6) although
abundance was greater in both dune forest and grassland than in sand forest. Biogeographical
classification indicated that >40% of the species are endemic to the
east coast of southern Africa with the remainder centred in adjacent savanna. Endemic
east coast species were well represented in both forest (15) and grassland
(11). Savanna species were better represented in grassland (27) than forest (8).
Proportions of grassland species and their abundance declined across increasing patch sizes of sand forest becoming lowest in dune forest.
CONCLUSIONS : Conservation of endemic, east coast dung beetle species requires
the preservation of both natural grassland and sizeable patches of forest in an
undisturbed habitat mosaic. As the east coastal system is relatively small in extent
with the MCE widely transformed in South Africa, the MSR is an important contributor
to regional conservation of endemic species.
