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Fine-scale spatial heterogeneity influences biodiversity and ecosystem productivity at many scales. In savanna systems, Macrotermes termites, through forming spatially explicit mounds with unique woody plant assemblages, emerge as important sources of such heterogeneity. Despite a growing consensus regarding the importance of functional diversity (FD) to ecosystem processes, no study has quantified how termite mounds affect woody plant FD. We address whether termite mounds alter the distribution of functional traits, and increase FD of woody plant communities within Africa's largest savanna woodland, the 2.7 million km miombo system. Using plant traits that change according to soil resources (for example, water and nutrients), and disturbance (for example, fire and elephant herbivory), we identified response functional groups and compared relative representation of these groups between mound and matrix habitats. We also asked whether mound and matrix habitats differed in their contribution to FD within the system. Although species representing most functional groups were found in both mound and matrix habitats, relative abundance of functional groups differed between mound and matrix. Mound plant assemblages had greater response diversity to soil resources than matrix plots, but there was no difference in response diversity to disturbance. High trait values on mounds included tree height, leaf nitrogen, phosphorus, and palatability. Species with root ectomycorrhizae dominated the matrix. In conclusion, these small patches of nutrient-enriched substrate emerge as drivers of FD in above-ground woody plant communities. [ABSTRACT FROM AUTHOR]

A wide range of bioenergetic, production, life history and ecological traits scale with body size in vertebrates. However, the consequences of differences in community body-size structure for ecological processes have not been explored. We studied the scaling relationships between body mass, shoulder height, hoof area, stride length and daily ranging distance in African ungulates ranging in size from the 5 kg dik-dik to the 5,000 kg African elephant, and the implications of these relationships on the area trampled by single and multispecies herbivore communities of differing structure. Hoof area, shoulder height and stride length were strongly correlated with body mass (Pearson's r >0.98, 0.95 and 0.90, respectively). Hoof area scaled linearly to body mass with a slope of unity, implying that the pressures exerted on the ground per unit area by a small antelope and an elephant are identical. Shoulder height and stride length scaled to body mass with similar slopes of 0.32 and 0.26, respectively; larger herbivores have relatively shorter legs and take relatively shorter steps than small herbivores, and so trample a greater area of ground per unit distance travelled. We compared several real and hypothetical single- and multi-species ungulate communities using exponents of between 0.1 and 0.5 for the body mass to daily ranging distance relationship and found that the estimated area trampled was greater in communities dominated by larger animals. The impacts of large herbivores are not limited to trampling. Questions about the ecological implications of community body-size structure for such variables as foraging and food intake, dung quality and deposition rates, methane production, and daily travelling distances remain clear research priorities. [ABSTRACT FROM AUTHOR]

Hunting lions while their populations are declining in much of Africa is a highly controversial issue. However, hunting for lions and other charismatic large mammals in Africa has contributed to maintaining large areas of wild land for lions and wildlife conservation. To minimise the impacts of hunting lions in some 150,000 km2 of Game Management Areas (total ∼190,000 km2) in Zambia an age-based quota setting system has been adopted. The approach involves reducing the number of lions taken to one per hunting block and limiting trophy hunting to past prime male lions. The age-based assessment criteria and the results from assessing the trophies taken in 2017 and 2018 are presented. Of the 18 trophies taken in 2017, 11% were judged to be under age, 17% were marginal and the remaining 72% were acceptable trophies of animals aged 6 years or older, with 28% being ≥7 years or older. The results for 2018 showed a higher proportion (42%) of older lions (≥7 years) being taken. Legal instruments to give force to the guidelines on trophies that can legally be hunted are being introduced to ensure the sustainable offtake of past prime male lions with minimal disruption of pride coalitions. These developments will contribute to improved management of lion hunting in Zambia and to meeting the non-detriment finding and conservation enhancement requirements of European and American regulations governing the importation of lion trophies. [ABSTRACT FROM AUTHOR]

Examines the use of community-based natural resource management (CBNRM) in Africa. Focus on large mammals; Features of CBNRM programs; Factors in their success; CBNRM in Zimbabwe; Use of computer technology and quantitative modeling; Partnerships between scientists and villagers; Reestablishing native species; Tie between conservation and use of natural resources.