Journal compilation CSIRO 2011
eastern Africa where it can cause significant crop losses. Mastomys natalensis is known to consume a variety of food
in response to the availability of food items. However, it is currently unknown whether maize crop growth stages affect
the spatio-temporal diet of this species.
Aims. We examined the foods consumed by M. natalensis in different habitats and seasons in central Tanzania and
Swaziland.
Methods. Diet was investigated in Tanzania in four different habitats (woodland, vegetable gardens, maize fields and
fallow land) during different maize crop growth stages between March 2008 and February 2009. In Swaziland, this was
conducted in three habitats (fallow land, cultivated fields and pristine land) during three crop growth stages (pre-planting,
vegetative stage and post-harvest) between March 2008 and April 2009. Micro-histological examination of undigested
fragments from the stomachs of trapped animals was made whereby the preserved stomach content was placed in a Petri dish
and sorted using a 25 or 50 magnification binocular stereoscope. Stomach contents were identified as: grain and/or seeds
(both grasses and maize), plant material (roots, stems and leaves), invertebrates, pods of seeds, fruits (vegetable fruit such as
tomato), animal hairs and unidentified matter. If necessary, a lugol solution was used to determine the presence of starch for
maize and grass seeds or grains.
Key results. In both countries, grain predominated in the diet of M. natalensis. Statistical analyses showed that there were
no differences due to seasons or habitats. Therefore, the percentage volume and relative importance were the same across
habitats and seasons in both countries.
Conclusions. Our findings highlight clearly that M. natalensis is a generalist species feeding on available resources
depending on the season and the habitat. Its preference for grain may account for its abundance in maize plantations and
confirms it as one of the major pests in crop plantations, especially grain.
Implications. This information offers a useful tool for determining the pest status in different habitats and/or seasons. The
findings of this study have implications for agriculture and conservation.