Estimating the abundance and breeding success of territorial songbirds is challenging. Various types of surveys and analyses are available, but all receive some criticism in the literature, and most methods are rarely compared with results obtained using intensive monitoring efforts. We assessed the efficacy of transect and point‐count surveys to estimate the abundance of male Bobolinks (Dolichonyx oryzivorus) and detect evidence of nesting and fledging by comparing the results of those surveys to results from more intensive monitoring (i.e., spot mapping and nest monitoring). We monitored 36 fields (254 ha) of late‐harvest hay, restored grassland, and fallow fields in the Luther Marsh Wildlife Management Area and on four farms in southern Ontario, Canada, in 2018. Compared to the number of territories identified based on spot mapping (197), distance sampling analysis of transect survey data provided a more accurate estimate of the abundance of male Bobolinks (230, 95% CI: 187, 282) than N‐mixture models of transect (668, 95% CI: 332, 1342) and point‐count (337, 95% CI: 203, 559) data. Three visits to survey transects and five to point counts did not effectively detect evidence of Bobolink breeding (i.e., nesting or fledging) in fields compared to spot mapping and nest monitoring. Distance sampling analysis of transect data appears promising for estimating the number of Bobolink territories in an area, e.g., those impacted by conservation programs. If estimates of the number of nesting Bobolinks and frequency of fledging are of interest, spot mapping and nest monitoring could be implemented at a subset of sampled fields. Our results suggest that additional studies to evaluate model‐based estimates of abundance with the best available information (e.g., from spot mapping of marked or unmarked populations and nest monitoring) would be useful to ensure that robust estimates are provided to support population estimates and conservation actions.

中文翻译：

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通过样带和点计数调查评估山毛榉的丰度估计和繁殖证据

估计区域性鸣禽的丰满度和繁殖成功率具有挑战性。可以进行各种类型的调查和分析，但是所有文献都受到批评，并且大多数方法很少与使用密集监视工作获得的结果进行比较。我们评估了样方和点计数调查的有效性，以估计雄性Bobolinks（Dolichonyx oryzivorus），并通过将这些调查的结果与更深入的监控（即点测绘和嵌套监控）的结果进行比较，来检测出筑巢和出雏的证据。2018年，我们对路德沼泽野生动物管理区和加拿大安大略省南部四个农场的36个田地（254公顷）的晚收干草，恢复的草地和休耕地进行了监控。作图（197），对断面调查数据进行距离采样分析，比N提供了更准确的男性Bobolinks（230，95％CI：187，282）丰度估计混合（668，95％CI：332，1342）和点数（337，95％CI：203，559）数据的混合模型。相较于点测绘和巢监测，三次访问调查样点和五次点计数未能有效地检测出Bobolink繁殖（即筑巢或出雏）的证据。样带数据的距离采样分析似乎有望用于估计某个地区的Bobolink领土数量，例如受保护计划影响的领土。如果对嵌套波波林克斯的数量和出雏频率的估计很感兴趣，则可以在一部分采样场上实施斑点测绘和巢监测。我们的结果表明，需要进行更多的研究，以利用可获得的最佳信息来评估基于模型的丰度估算值（例如