Journal of Arid Environments Journal of Arid Environments 72 (2008) 820–835 Ecological and social characterization of key resource areas in Kenyan rangelands M.K. Ngugi à , R.T. Conant Natural Resources Ecology Laboratory, 1231 East Drive A245, Colorado State University, Fort Collins, CO 80523, USA Received 30 November 2006; received in revised form 19 September 2007; accepted 26 September 2007 Available online 7 November 2007 Abstract Key resource areas (KRAs), defined as dry season foraging zones for herbivores, were studied relative to the more extensive outlying rangeland areas (non-KRAs) in Kenya. Field surveys with pastoralists, ranchers, scientists and government officials delineated KRAs on the ground. Identified KRAs were mapped based on global positioning and local experts’ information on KRAs accessibility and ecological attributes. Using the map of known KRAs and non-KRAs, we examined characteristics of soils, climate, topography, land use/cover attributes at KRAs relative to non-KRAs. How and why do some areas (KRAs) support herbivores during droughts when forage is scarce in other areas of the landscape? We hypothesized that KRAs have fundamental ecological and socially determined attributes that enable them to provide forage during critical times and we sought to characterize some of those attributes in this study. At the landscape level, KRAs took different forms based on forage availability during the dry season but generally occurred in locations of the landscape with aseasonal water availability and/or difficult to access areas during wet season forage abundance. Greenness trends for KRAs versus non-KRAs were evaluated with a 22-year dataset of Normalized Difference Vegetation Index (NDVI). Field surveys of KRAs provided qualitative information on KRAs as dry season foraging zones. At the scale of the study, soil attributes did not significantly differ for KRAs compared to non-KRAs. Slopes of KRA were generally steeper compared to non-KRAs and elevation was higher at KRAs. Field survey respondents indicated that animals and humans generally avoid difficult to access hilly areas using them only when all other easily accessible rangeland is depleted of forage during droughts. Understanding the nature of KRAs will support identification, protection and restoration of critical forage hotspots for herbivores by strengthening rangeland inventory, monitoring, policy formulation, and conservation efforts to improve habitats and human welfare. r 2007 Elsevier Ltd. All rights reserved. Keywords: Drought; Forage; Foraging; Herbivore; Pastoralist; Rangeland; Satellite; Topography 1. Introduction Large extents of rangeland are interspersed with a few zones called key resource areas (KRAs), which provide forage during dry spells. Herbivore key resources refer to plants that grow in marginal ecosystems which have characteristics enabling them to act as drought refugia, dry season grazing, or forage reserves ARTICLE IN PRESS www.elsevier.com/locate/jaridenv 0140-1963/$ - see front matter r 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.jaridenv.2007.09.009 à Corresponding author. Tel.: +1 970 215 4009; fax: +1 970 491 1965. E-mail address: ngugi@cnr.colostate.edu (M.K. Ngugi).