Regional variation in the diet of martial eagles in the Cape Province, South Africa
The remains of 1542 prey individuals were collected at 35 martial eagle Polemaetus bellicosus nests and feeding perches to analyse, by number, the diet of the species in the Cape Province. Overall, hares are the dominant prey taxon (50% of the total), followed by striped polecat, genet, ground squirrel, and mongooses (14%). Juvenile domestic small-stock comprises 5%, of which a portion is likely to be carrion. The eagles, which tend to select prey in the 1-5 kg mass range, are opportunistic predators which take a wide spectrum of prey but which also exploit local abundances of suitable types. The effect of habitat variation on the diet, across an environmental gradient, was investigated by creating three groups of nests according to key environmental criteria pertinent to the four biomes in which they are located. The three groups, NW and SE Nama-Karoo (arid zone) and Grassland (moist zone), were compared according to relative proportions of prey taxa, and indices of general diversity and species richness. From the Nama-Karoo groups to the Grassland group the proportion formed by hares decreases from 63% to 13%, and that of birds increases from 7% to 32%. There is a statistically significant increase in prey diversity from each of the Nama-Karoo groups to the Grassland group, and in species richness from the SE Nama-Karoo group to the Grassland group. These findings are discussed in relation to differences in rainfall, topography, primary production, and vegetation cover and height between the Nama-Karoo and Grassland or Savanna Biomes.
No Reference information available - sign in for access.
No Citation information available - sign in for access.
No Supplementary Data.
No Article Media