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Landscape Ecology

, Volume 7, Issue 4, pp 229–241 | Cite as

Spatial variation in forage nutrient concentrations and the distribution of Serengeti grazing ungulates

  • Steven W. Seagle
  • S. J. McNaughton
Article

Abstract

Resident grazing ungulates in the Serengeti National Park, Tanzania, are conspicuously patchy in their distribution among regions of the Park. Linear programming models that maximize nitrogen (N) consumption by foraging ungulates in Serengeti regions having high and low resident animal densities were compared using forage ingestion rate and twelve nutritional requirements as simultaneously imposed constraints on forage choice. Model results indicate that (1) growing season N or crude protein is not limiting in either region although greater N ingestion is possible within the eastern corridor under other nutritional constraints, (2) grazing ungulates in the eastern corridor region occur in greater density and are capable of balancing dietary requirements solely from forage while simultaneously consuming more protein than ungulates in the northeast region, and (3) rarer landscape elements are most capable of providing ungulate dietary requirements in both the northeast and eastern corridor. These results provide a nutritional basis to understand patchy spatial distributions of grazers within Serengeti regions and landscapes, and provide a partial test of the hypothesis that large generalist herbivores should graze rare forages more frequently. The ability of uncommon landscape elements to support ungulate grazing over the growing season is supported by previous ecosystem studies that demonstrate the capability of grass forages for compensatory growth and the ability of grazing to stimulate rapid nutrient recycling.

Keywords

Serengeti ungulates nutritional requirements landscape grazing 

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Copyright information

© SPB Academic Publishing bv 1992

Authors and Affiliations

  • Steven W. Seagle
    • 1
  • S. J. McNaughton
    • 2
  1. 1.University of Maryland, Appalachian Environmental LaboratoryFrostburgUSA
  2. 2.Biological Research Laboratories, Syracuse UniversitySyracuseUSA

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