Postgraduate Programme in Ecology, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
Ecology and Conservation of Amazonian Vertebrates Research Group, Federal University of Amapá, Macapá, Amapá, Brazil.
PeerJ. 2022 Oct 20;10:e14287. doi: 10.7717/peerj.14287. eCollection 2022.
Although previous studies demonstrate declines in many large bodied species following hydropower dam installation, others suggest that some species, including the giant otter () may return to newly created reservoir habitats. Yet, there is a lack of evidence to support such theories. Here, we analyzed the effects of a hydropower dam on giant otters using a before-after control-impact study design in the eastern Brazilian Amazon. We collected data 3 years before (2011-2012 and 2015) and after (2017-2019) dam construction, totaling 6,459 km of surveys along rivers with 43 direct sightings of giant otters. Contrary to expectations, our results revealed that giant otters did not remain nor did they return to the dam reservoir. Beyond the zone directly impacted by the dam giant otter occurrence and relative abundance declined next to sustainable-use reserves where the river was more intensely used by people. Our study showed that in the absence of active management sustainable-use reserves and low human density were not sufficient to maintain this apex-predator. Our findings suggest a need to proactively create and maintain areas with low levels of anthropogenic disturbance to enable sustainable coexistence between energy demands and biodiversity across Amazonia.
虽然先前的研究表明，在水力发电大坝建成后，许多大型物种的数量有所减少，但也有研究表明，包括大水獭（）在内的一些物种可能会返回新形成的水库栖息地。然而，缺乏证据支持这些理论。在这里，我们使用巴西亚马逊东部的前后对照控制影响研究设计，分析了一座水力发电大坝对大水獭的影响。我们在大坝建设之前（2011-2012 年和 2015 年）和之后（2017-2019 年）收集了数据，总共沿着有 43 次大水獭直接目击的河流进行了 6459 公里的调查。与预期相反，我们的结果表明，大水獭既没有留下来，也没有返回大坝水库。在大坝直接影响区之外，靠近可持续利用保护区，河流被人类更频繁地使用，大水獭的出现和相对丰度下降。我们的研究表明，在没有积极管理的情况下，可持续利用保护区和低人类密度不足以维持这种顶级捕食者。我们的研究结果表明，需要积极创建和维护低人为干扰区，以实现亚马逊地区能源需求和生物多样性之间的可持续共存。
