SNAPSHOT USA is a multicontributor, long‐term camera trap survey designed to survey mammals across the United States. Participants are recruited through community networks and directly through a website application (https://www.snapshot-usa.org/). The growing Snapshot dataset is useful, for example, for tracking wildlife population responses to land use, land cover, and climate changes across spatial and temporal scales. Here we present the SNAPSHOT USA 2021 dataset, the third national camera trap survey across the US. Data were collected across 109 camera trap arrays and included 1711 camera sites. The total effort equaled 71,519 camera trap nights and resulted in 172,507 sequences of animal observations. Sampling effort varied among camera trap arrays, with a minimum of 126 camera trap nights, a maximum of 3355 nights, a median 546 nights, and a mean 656 ± 431 nights. This third dataset comprises 51 camera trap arrays that were surveyed during 2019, 2020, and 2021, along with 71 camera trap arrays that were surveyed in 2020 and 2021. All raw data and accompanying metadata are stored on Wildlife Insights (https://www.wildlifeinsights.org/), and are publicly available upon acceptance of the data papers. SNAPSHOT USA aims to sample multiple ecoregions in the United States with adequate representation of each ecoregion according to its relative size. Currently, the relative density of camera trap arrays varies by an order of magnitude for the various ecoregions (0.22–5.9 arrays per 100,000 km2), emphasizing the need to increase sampling effort by further recruiting and retaining contributors. There are no copyright restrictions on these data. We request that authors cite this paper when using these data, or a subset of these data, for publication. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the US Government.

中文翻译：

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2021 年美国快照：美国第三次全国相机陷阱协调调查

SNAPSHOT USA 是一项多方参与的长期相机陷阱调查，旨在调查美国各地的哺乳动物。参与者是通过社区网络和直接通过网站应用程序招募的（https://www.snapshot-usa.org/）。不断增长的快照数据集非常有用，例如，可用于跟踪野生动物种群对空间和时间尺度上的土地利用、土地覆盖和气候变化的反应。在这里，我们介绍 SNAPSHOT USA 2021 数据集，这是美国第三次全国相机陷阱调查。数据是通过 109 个相机陷阱阵列收集的，包括 1711 个相机站点。总工作量相当于 71,519 个相机陷阱夜晚，并产生了 172,507 个动物观察序列。相机陷阱阵列的抽样工作量有所不同，最少为 126 个相机陷阱夜晚，最多为 3355 个夜晚，中位数为 546 个夜晚，平均为 656 ± 431 个夜晚。第三个数据集包含 2019 年、2020 年和 2021 年调查的 51 个相机陷阱阵列，以及 2020 年和 2021 年调查的 71 个相机陷阱阵列。所有原始数据和随附元数据都存储在 Wildlife Insights 上（https://www.wildlifeinsights.org/），并在数据论文被接受后公开。 SNAPSHOT USA 旨在对美国的多个生态区进行抽样，并根据每个生态区的相对规模充分代表性。目前，不同生态区的相机陷阱阵列的相对密度存在一个数量级的差异（每 100,000 公里 0.22-5.9 个阵列）2），强调需要通过进一步招募和留住贡献者来增加抽样工作。这些数据没有版权限制。我们要求作者在使用这些数据或这些数据的子集进行出版时引用本文。任何贸易、公司或产品名称的使用仅用于描述目的，并不意味着美国政府的认可。