Capture-Mark-Release (Mark-Release-Recapture) Records of Rainbow Scarabs (<em>Phanaeus vindex</em>) from Two Farms in SE-Michigan

Until now, little is known about the population structure and mobility of temperate dung beetles including the rainbow scarab <em>Phanaeus vindex</em> (MacLeay 1819) although this knowledge is essential for their conservation as pastures become increasingly rare and the landscape fragmented by monocultures and urbanization. Here, we estimate population size, longevity, and dispersal within and between pastures. For three years, we life-trapped beetles every week on 2 adjacent farms in SE-Michigan, determined their sex, male morph, and size, and marked their elytra with individual tattoo patterns before releasing them. We marked a total of 470 rainbow scarabs of which 14 were recaptured once and two were recaptured twice. The sex ratio was not significantly sex-biased but fluctuated between months with no apparent uniformity between years. While the minor to major male ratios were unbiased in 2019 and 2020, they were marginally minor-biased in 2021. The gross population estimates for the two farms were 458-491 and 217 rainbow scarabs, respectively. Beetles travelled distances of up to 178 m within farms. No beetles dispersed between farms. One large female was recaptured after 338 days documenting the first cold hardiness and long lifespan of a cold-temperate dung beetle species. The low population estimates on both farms indicate two vulnerable populations with no or extremely limited connectivity. Supplementary funding for the land stewardship of small-scale cattle farmers could stabilize populations of native dung beetles and maintain their ecosystem services.迄今为止，学界对温带蜣螂的种群结构与活动模式仍知之甚少，其中包括彩虹蜣螂（Phanaeus vindex，MacLeay 1819）；然而随着牧场日益稀缺、景观被单一栽培与城市化割裂，这类昆虫的保护亟需此类基础研究数据。本研究针对密歇根州东南部两座相邻牧场，开展了为期三年的每周活体诱捕调查，以估算该类蜣螂的种群规模、寿命以及牧场内外的扩散能力。调查过程中，我们对捕获的蜣螂进行性别、雄性表型与体型判定，并通过在鞘翅上印制个性化纹身标记的方式完成个体标记后放归。本次研究共计标记了470头彩虹蜣螂，其中14头被再次捕获1次，2头被捕获2次。种群性比未出现显著偏倚，但各月份间存在波动，且不同年份间未呈现统一规律。2019年与2020年的雄性大小型个体比例未出现偏倚，但2021年该比例略偏向小型雄性。两座牧场的总种群估算规模分别为458~491头与217头彩虹蜣螂。个体在单座牧场内的移动距离可达178米，但未发现跨牧场的扩散事件。另有1头大型雌性个体在被标记338天后再次被捕获，这是首个关于寒温带蜣螂物种耐寒性与长寿命的记录。两座牧场的种群估算规模均偏低，说明其种群均处于脆弱状态，且种群间几乎不存在基因交流或交流程度极低。为小型牧场主提供土地管理配套资助，可帮助稳定本土蜣螂种群，进而维持其生态系统服务功能。

搜集汇总

背景与挑战

背景概述

该数据集记录了在密歇根州东南部两个农场对彩虹金龟子（Phanaeus vindex）进行的标记-释放-重捕研究，涵盖2019年至2021年的数据，包括470只标记个体、重捕记录、种群大小估计（分别为458-491只和217只）、性别比、雄性形态比例以及移动距离（最远178米）。研究揭示了种群脆弱性和缺乏农场间扩散，为温带粪金龟子保护提供了关键生态学数据。