Abstract:
Small mammal communities were sampled at eight sites along an altitudinal gradient in the Groot Swartberg Mountains of the southern Cape. The plant communities sampled at each of these sites represented different altitudinal zones and rainfall regimes. Vegetation cover {as expressed by a point cover survey and foliage profiles) increased with increasing altitude and rainfall. Foliage cover was however compressed into the lower layers of the foliage profile at high altitudes. were inversely related. Rock and plant cover the small mammal communities reached higher density and alpha diversity in fynbos heathlands than in either fynbos shrublands or succulent karoo shrublands. Population densities of some species e.g. Acomys subspinosus and Otomys irroratus increased during the 15 month trapping period while those of Rhabdomys pumilio and Aethomys namaquensis decreased. Breeding of all species occurred throughout the year and the diet of the various species differed. The population density of some species, e.g. A. subspinosus, 0. irroratus and R. pumilio increased with increasing altitude. Alpha diversity increased with increasing altitude and hence probably with increasing rainfall and productivity. Alpha diversity in fynbos communities were similar to those recorded in other biomes. Beta diversity or species turnover was greatest between sites on the arid end of the moisture gradient.
