Browsing and plant traits in nutrient-rich and nutrient-poor savannas in Tanzania. (3rd November 2017)

• Record Type: Journal Article
• Authors: Mramba, Rosemary P.; Andreassen, Harry P.; Skarpe, Christina
• Is Part Of: Journal of tropical ecology. Volume 33:Part 5(2017:Sep.)
• Page Start: 327
• Page End: 336
• Publication Date: 2017-11-03
• Subjects: Aepyceros melampus, -- Africa, -- browsing height, -- Giraffa camelopardalis, -- leaf size, -- Loxodonta africana, -- Mikumi National Park, -- Serengeti National Park, -- soil nutrient, -- spinescence; Ecology -- Tropics -- Periodicals; 577.0913
• DOI: 10.1017/S026646741700030X
• Languages: English
• ISSNs: 0266-4674

Abstract

Abstract: Environmental productivity is important in determining defensive or tolerance traits of plants, with nutrient-rich savannas showing tolerance and nutrient-poor showing defence traits. Animals are affected differently by such traits due to differences in size, and other characters. We studied differences in browsing as a response to plant traits by elephant, giraffe and impala in Mikumi, a nutrient-poor savanna, and Serengeti, a nutrient-rich savanna, both in Tanzania, for a total of 4 mo; 2 mo at each site. Browsing time on a plant, species and height browsed were recorded. Spinesence reduced biting rate by elephant in Serengeti to 3.8 bites min −1, compared with 4.7 without spines, but had no effect on impala or giraffe. Leaf size affected biting rate by giraffe, decreasing with size in Serengeti from 19.8 bites min −1 to 17.4 bites min −1, increasing in Mikumi, from 17.7 to 19.5 bites min −1, but did not differ in elephant and impala. Biting rate by elephant in Serengeti decreased with browsing height from 0.6 m to 4.2 m and by impala in Mikumi decreased from 0.25 m to 1.5 m, while that of giraffe in Mikumi increased with browsing height, peaking at 4.2 m. The effect was comparable for elephant and impala.