Pretorius Mariëtte, Markotter Wanda, Keith Mark
Centre for Viral Zoonoses, Department of Medical Virology, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
Mammal Research Institute, Department of Zoology and Entomology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria, South Africa.
BMC Zool. 2021;6(1):31. doi: 10.1186/s40850-021-00095-5. Epub 2021 Nov 20.
Modification and destruction of natural habitats are bringing previously unencountered animal populations into contact with humans, with bats considered important zoonotic transmission vectors. Caves and cave-dwelling bats are under-represented in conservation plans. In South Africa, at least two cavernicolous species are of interest as potential zoonotic hosts: the Natal long-fingered bat and the Egyptian fruit bat . Little information is available about the anthropogenic pressures these species face around important roost sites. Both bats are numerous and widespread throughout the country; land-use changes and urban expansions are a rising concern for both conservation and increased bat-human contact.
Our study addressed this shortfall by determining the extent of land-cover change around 47 roosts between 2014 and 2018 using existing land cover datasets. We determined the land-cover composition around important roost sites (including maternity, hibernacula and co-roosts), distances to urban settlements and assessed the current protection levels of roost localities. We detected an overall 4% decrease in natural woody vegetation (trees) within 5 km buffer zones of all roost sites, with a 10% decrease detected at co-roost sites alone. Agricultural land cover increased the most near roost sites, followed by plantations and urban land-cover. Overall, roosts were located 4.15 ± 0.91 km from urban settlements in 2018, the distances decreasing as urban areas expand. According to the South African National Biodiversity Institute Ecosystem Threat Status assessment, 72% of roosts fall outside of well-protected ecosystems.
The current lack of regulatory protection of cavernicolous bats and their roosts, increasing anthropogenic expansions and proximity to human settlements raises concerns about increased human-bat contact. Furthermore, uncontrolled roost visitation and vandalism are increasing, contributing to bat health risks and population declines, though the extent of roosts affected is yet to be quantified. In an era where pandemics are predicted to become more frequent and severe due to land-use change, our research is an urgent call for the formal protection of bat-inhabited caves to safeguard both bats and humans.
The online version contains supplementary material available at 10.1186/s40850-021-00095-5.
自然栖息地的改变和破坏使以前未接触过的动物种群与人类接触，蝙蝠被认为是重要的人畜共患病传播媒介。洞穴及穴居蝙蝠在保护计划中的代表性不足。在南非，至少有两种洞穴物种作为潜在的人畜共患病宿主受到关注：纳塔尔长指蝠和埃及果蝠。关于这些物种在重要栖息地周围面临的人为压力，我们所知甚少。这两种蝙蝠在该国数量众多且分布广泛；土地利用变化和城市扩张对保护以及增加蝙蝠与人类的接触而言，都是日益令人担忧的问题。
我们的研究通过使用现有的土地覆盖数据集，确定了2014年至2018年间47个栖息地周围土地覆盖变化的程度，解决了这一不足。我们确定了重要栖息地周围的土地覆盖组成（包括繁殖地、冬眠地和共栖地）、到城市定居点的距离，并评估了栖息地所在地目前的保护水平。我们检测到所有栖息地5公里缓冲区内的天然木本植被（树木）总体减少了4%，仅共栖地就减少了10%。栖息地附近农业用地覆盖增加最多，其次是种植园和城市土地覆盖。总体而言，2018年栖息地距离城市定居点4.15±0.91公里，随着城市地区扩张，距离在缩短。根据南非国家生物多样性研究所的生态系统威胁状况评估，72%的栖息地位于保护良好的生态系统之外。
目前对洞穴蝙蝠及其栖息地缺乏监管保护，人为扩张不断增加以及与人类住区距离更近，引发了对人类与蝙蝠接触增加的担忧。此外，不受控制的栖息地探访和破坏行为不断增加，导致蝙蝠面临健康风险和种群数量下降，尽管受影响栖息地的范围尚未量化。在一个预计由于土地利用变化大流行将变得更加频繁和严重的时代，我们的研究迫切呼吁对蝙蝠栖息的洞穴进行正式保护，以保护蝙蝠和人类。
在线版本包含可在10.1186/s40850-021-00095-5获取的补充材料。
