The rock ptarmigan (Lagopus muta) has a wide Holarctic geographical range, within which its status changes locally from threatened to abundant. For the correct management of populations under differing scenarios, accurate and precise estimates of bird abundances and/or densities are required. We used geolocated datasets from 56 counts of singing males carried out in 2003–2017 to estimate the density of Pyrenean rock ptarmigans (Lagopus muta pyrenaica). We analysed these datasets using two methodologies: (1) a plot sampling (PS) approach with two effective detection ranges (EDR) of 250 m and 350 m and (2) a conventional distance sampling (DS) approach. Our results showed that the density estimates obtained by DS were more precise and 30–87% higher than those obtained by PS using 250 m and 350 m EDR. Monitoring with PS underestimates populations and is less precise than DS; this bias is magnified when high EDR values are used. The monitoring of the Pyrenean rock ptarmigan could be significantly improved with greater use of the DS method.

中文翻译：

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距离抽样与地块抽样以监测比利牛斯山雷鸟的种群数量

雷鸟岩石（Lagopus muta）具有宽广的Holarctic地理范围，在该范围内其地位从受威胁的状态变为富裕的状态。为了在不同情况下正确管理种群，需要准确，准确地估计鸟类的丰度和/或密度。我们使用2003-2017年进行的56个歌唱雄性的地理定位数据集来估算比利牛斯山岩雷鸟（Lagopus muta pyrenaica）。我们使用两种方法来分析这些数据集：（1）具有250 m和350 m的两个有效检测范围（EDR）的地块采样（PS）方法，以及（2）传统的距离采样（DS）方法。我们的结果表明，与使用250 m和350 m EDR的PS所获得的密度估计相比，DS所获得的密度估计更加精确且高出30–87％。PS的监测低估了人口，并且不如DS精确；当使用高EDR值时，此偏差会放大。通过更多地使用DS方法，可以大大改善对比利牛斯山岩雷鸟的监测。