The feeding behaviour of giraffes in the Kruger National Park, South Africa, was observed over 12 months and the diet analysed for condensed tannin content. Supportive evidence was found for plant defence against excessive browsing by means of tannin biosynthesis. Condensed tannin negatively influenced acceptability and nutritional value of dietary browse to giraffes. The giraffes avoided high condensed tannin levels. Tannin content of dietary foliage increased due to browse disturbance. Tannin levels fluctuated daily within the canopy of individual plants in relation to change in temperature, light intensity and phenological status of the foliage.
Keywords: Giraffe, Tannin, Chemical defence, Browse, Feeding ecology, Herbivore plant interaction
Authors: D. Furstenburg and W. van Hoven
Journal: Comparative Biochemistry and Physiology Part A: Physiology