Feeding-height stratification among African browsing ruminants

This study investigated the hypothesis that the use of different feeding levels in the vegetation promotes resource partitioning among browsing ungulate species in African savannas. Focal animal feeding observations, recorded on a real-time basis using computerized data-capture system, were conducted on giraffe (Giraffa camelopardalis Linnaeus), kudu (Tragelaphus steosiceros Pallas), impala (Aepyceros melampus Lichtenstein) and steenbok (Raphicerus campestris Thunberg) in the central region of the Kruger National Park, South Africa, Although there was clear stratification in mean feeding heights among the four species throughout the seasonal cycle, there was considerable overlap in the feeding-height ranges of kudu, impala and steenbok. Hence, feeding-height stratification probably only separates giraffe from other species. Giraffe bulls fed at a higher level in the vegetation than cows, often with head and neck extended vertically. It is suggested that bulls benefit in this by gaining access to nutritious new shoots in the upper canopy, but may suffer an increased predation cost due to reduced vigilance when in this posture.

Last Updated
January 26, 2021
Size
415.70 KB