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The aim of this study was to understand how communities of adult and juvenile (seedlings and saplings) woody plants were impacted by fire and the 2014–2016 El Niño drought in Kruger National Park, South Africa. We used a landscape‐scale fire experiment spanning 2013–2019 in a semi‐arid savanna in the central west of Kruger National Park (mean annual precipitation, 543 mm). Adult and juvenile woody species composition were recorded during and after the drought in 40 plots that experienced a mix of no fire, moderate fire, and frequent fire treatments. Using multivariate modeling, we related community composition in juvenile and adult woody plants to year of sampling and the experimental fire treatments. Post‐drought, there was significant adult woody plant top‐kill, especially in dominant species Dichrostachys cinerea (81% reduction in abundance), Acacia nigrescens (30%), and Combretum apiculatum (19%), but there was no significant change in adult species richness. Two years post‐drought, abundance of all juveniles decreased by 35%, and species richness increased in juveniles in both the frequent fire (7%) and no fire treatments (32%). Counter‐intuitively, the El Niño drought increased species richness of the woody plant community due to the recruitment of new species as juveniles, a potential lasting impact on diversity, and where different fire regimes were associated with differences in community composition. Drought events in semi‐arid savannas could drive temporal dynamics in species richness and composition in previously unrecognized ways. [ABSTRACT FROM AUTHOR]

Grazing lawn and flammable-tussock grass communities are contrasting resource pools for mammalian grazers in terms of forage quantity and quality. Drought events fundamentally alter forage availability within these communities and therefore should alter herbivore use with repercussions for the recovery and functioning of ecosystems after drought. During and after an intense El Niño drought (2014–2017) in Kruger National Park, South Africa, we addressed two questions: (1) how does herbivore use of different grass types change during a drought and (2) how do these changes affect grass productivity post-drought? We monitored grazer use of three different grass communities (lawn, tussock and burned-tussock) at a landscape scale and measured primary productivity monthly during and post-drought. For the first drought year, grazer numbers were highest on grazing lawn communities. This pattern continued into the second dry growing season, until herbivores finally left the study area. Both lawns and tussock grasslands recovered rapidly after the first good rainfall (productivity > 150 g m−2 per month). However, grazers did not return to feed on the same patches they had frequented pre-drought resulting in grazing lawn grasses self-shading and senescing. Longer droughts have the potential to decouple grazers and grazing lawns with negative impacts on lawn productivity and persistence that could drive the loss of lawns in savanna landscapes and impact mesoherbivore populations. It is clear from our results that grazer effects need to be incorporated into drought frameworks to understand the consequences of droughts for grassland function. [ABSTRACT FROM AUTHOR]