The Okavango River Basin is a hotspot of bat diversity that requires urgent and adequate protection. To advise future conservation strategies, we investigated the relative importance of a range of potential environmental drivers of bat species richness and functional community composition in the Okavango River Basin. During annual canoe transects along the major rivers, originating in the central Angolan highlands, we recorded more than 25,000 bat echolocation calls from 2015 to 2018. We corrected for possible biases in sampling design and effort. Firstly, we conducted rarefaction analyses of each survey year and sampling appeared to be complete, apart from 2016. Secondly, we used total activity as a measure of sample effort in mixed models of species richness. Species richness was highest in the Angola Miombo Woodlands and at lower elevations, with higher minimum temperatures. In total, we identified 31 individual bat species. We show that even when acoustic surveys are conducted in remote areas and over multiple years, it is possible to correct for biases and obtain representative richness estimates. Changes in habitat heterogeneity will have detrimental effects on the high richness reported here and human land-use change, specifically agriculture, must be mediated in a system such as the Angolan Miombo Woodland.

中文翻译：

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奥卡万戈河流域大断面的蝙蝠物种丰富度和群落组成

奥卡万戈河流域是蝙蝠多样性的热点，需要紧急和适当的保护。为了建议未来的保护策略，我们调查了奥卡万戈河流域蝙蝠物种丰富度和功能群落组成的一系列潜在环境驱动因素的相对重要性。在始于安哥拉中部高地的主要河流的年度独木舟横断面上，我们记录了从2015年到2018年的25,000多只蝙蝠回声定位记录。我们纠正了采样设计和工作量方面的可能偏差。首先，我们对每个调查年度进行了稀有度分析，除2016年外，抽样工作似乎都已完成。其次，我们在物种丰富度混合模型中使用了总活动作为衡量样本工作量的指标。安哥拉Miombo森林地的物种丰富度最高，海拔较低时，最低温度更高。总共，我们确定了31种蝙蝠个体。我们表明，即使在偏远地区进行了多年的声学勘测，也有可能纠正偏差并获得代表性的丰富度估算值。栖息地异质性的变化将对这里报道的高丰度产生不利影响，人类土地利用的变化，特别是农业，必须在诸如安哥拉米伦坡林地这样的系统中进行调节。