Makati Anastacia A, Songhurst Anna, Bennitt Emily, Masunga Gaseitsiwe S, McCulloch Graham, Stronza Amanda, Matsika Tiroyaone A, Eckardt Frank D
Okavango Research Institute University of Botswana Maun Botswana.
Environmental and Geographical Science University of Cape Town Rondebosch South Africa.
Ecol Evol. 2025 Jan 9;15(1):e70758. doi: 10.1002/ece3.70758. eCollection 2025 Jan.
African elephants () are megaherbivores of the African savannas requiring extensive ranges that can provide critical resources for their survival and reproduction at different spatiotemporal scales. We studied seasonal differences in home range sizes and daily distance to the nearest surface water sources by five male and 10 female African elephants in the eastern Okavango Panhandle in northern Botswana between 2014 and 2017. We hypothesized that (i) elephant home ranges would be larger in the wet than in the dry season (because critical resources tend to be less localized in the wet than in the dry season), (ii) the daily distance of the elephants to the nearest ephemeral surface water sources would be larger in the dry than in the wet season because many of the ephemeral water sources would be dry in the dry season and elephants would start moving towards permanent water sources such as rivers, and lastly (iii) that the differences in elephant home ranges and daily distance to water would differ between sexes. Our results showed that elephant home ranges were larger in the wet than in the dry season, and that they differed between sexes with female elephants having smaller home ranges in the late wet season. The mean daily distance to the nearest ephemeral surface water sources was larger in the dry than in the wet season. There was an inverse relationship between elephants' daily distance to permanent surface water and to ephemeral water sources. The findings indicate the need for large conservation areas and functional connectivity between landscapes to enable the highly mobile savanna elephants to access critical seasonal resources such as water and forage in semi-arid savannas. Such landscapes are critical, especially in the face of climate change, when high air temperatures and droughts may exacerbate forage and water shortage and intensify human-elephant interactions in surrounding agroecosystems.
非洲象是非洲稀树草原的巨型食草动物,需要广阔的活动范围,以便在不同的时空尺度上为其生存和繁殖提供关键资源。2014年至2017年期间,我们研究了博茨瓦纳北部奥卡万戈河三角洲东部五条雄性和十条雌性非洲象的活动范围大小的季节性差异,以及它们与最近地表水水源的每日距离。我们假设:(i)大象的活动范围在雨季比旱季更大(因为关键资源在雨季往往比旱季分布得更分散);(ii)大象与最近的季节性地表水水源的每日距离在旱季比雨季更大,因为许多季节性水源在旱季会干涸,大象会开始向河流等永久性水源移动;最后(iii)大象的活动范围和与水源的每日距离的差异在性别之间存在不同。我们的研究结果表明,大象的活动范围在雨季比旱季更大,而且在性别之间存在差异,雌性大象在雨季后期的活动范围较小。与最近的季节性地表水水源相比,大象到永久性地表水水源的平均每日距离在旱季比雨季更大。大象到永久性地表水水源的每日距离与到季节性水源的每日距离之间存在反比关系。这些发现表明,需要大型保护区以及景观之间的功能连通性,以使高度移动的稀树草原大象能够获取半干旱稀树草原中的关键季节性资源,如水和草料。这样的景观至关重要,尤其是在面对气候变化时,高温和干旱可能会加剧草料和水资源短缺,并强化周边农业生态系统中人与大象的相互作用。