[en] We studied the diet composition of Northern Grey-headed Sparrow Passer
griseus and Southern Red Bishop Euplectes orix in four localities of the
Rusizi Plain, northwest Burundi. We analyzed crop contents of 100 adults
from each of the two species and the composition of food brought by parents
to nestlings of the sparrow at ten nests. In all four sites, the sparrow’s diet
consisted primarily of rice. The bishop also fed mostly on rice grains but also
ate Lepidoptera caterpillars, some other insects and wild grass seeds such as
Panicum sp. and Brachiaria sp. For adults of both bird species, there was no
significant variation in diet throughout the year. However, the diet of young
sparrows was much more diverse and changed from the day of hatching until
fledging. On the day of hatching, chicks ate mainly caterpillars but by the
tenth day, food items comprised one third caterpillars, one third Orthoptera
and the rest of other insects including Odonata, Dictyoptera, Isoptera and
adult Lepidoptera. After this and until fledging, the chicks were fed
increasingly on rice seeds. Simultaneously, the proportion of caterpillars taken
gradually decreased until none was fed to the nestlings at the end of the
nestling period. The items brought by parents also varied with time of day,
with caterpillars and grasshoppers in higher proportions in the morning,
decreasing around mid-day and then increasing in the evening.
