The Andean Ibis (Theristicus branickii) is discontinuously distributed in western South America from Ecuador to northern Chile. In Ecuador, it inhabits high elevations (>3,700 m) where it is classified as critically endangered because of its low population number caused by hunting and habitat loss. However, the population size of Andean Ibis in Ecuador is unknown, hindering the implementation of conservation actions. We performed a survey to estimate the abundance of Andean Ibis in the Ecuadorian Andes. In February 2016, and January 2017 and 2018, we conducted 11 point counts. Point counts were located in two provinces, each point count had nine 30-min visits. We recorded Andean Ibis in eight point counts, all in the Province of Napo. Detectability was explained by the amount of nontree vegetation cover and terrain slope, whereas abundance corresponded to gross primary productivity, annual mean temperature, and annual precipitation. We estimated there were 85 (95% credible interval [CI]: 63–117), 94 (95% CI: 32–125), and 134 (95% CI = 77–210) individuals of Andean Ibis in 2016, 2017, and 2018, respectively. The fact that abundance increased in the past 3 years could be explained by an increase in gross primary productivity. We suggest continuing population monitoring and adopting the sampling protocol and data analysis methods presented here as a baseline to better understand the spatiotemporal variation in abundance.

中文翻译：

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估计厄瓜多尔北部高安第斯山脉的安第斯朱鹭 (Theristicus branickii) 的数量

安第斯朱鹮（Theristicus branickii）在南美洲西部从厄瓜多尔到智利北部间断分布。在厄瓜多尔，它栖息在高海拔（> 3,700 m），由于狩猎和栖息地丧失导致其数量少，因此被列为极度濒危物种。然而，厄瓜多尔安第斯朱鹮的种群规模未知，阻碍了保护行动的实施。我们进行了一项调查，以估计厄瓜多尔安第斯山脉中安第斯朱鹭的数量。2016 年 2 月、2017 年 1 月和 2018 年，我们进行了 11 点统计。点计数位于两个省，每个点计数有 9 次 30 分钟的访问。我们记录了八点安第斯宜必思，全部在纳波省。可探测性由非树木植被覆盖量和地形坡度解释，而丰度则对应于总初级生产力、年平均温度和年降水量。我们估计 2016 年、2017 年有 85（95% 可信区间 [CI]：63-117）、94（95% CI：32-125）和 134（95% CI = 77-210）个体安第斯朱鹭，和 2018 年。过去 3 年丰度增加的事实可以用总初级生产力的增加来解释。我们建议继续进行种群监测并采用此处介绍的采样协议和数据分析方法作为基线，以更好地了解丰度的时空变化。和 2018 年。过去 3 年丰度增加的事实可以用总初级生产力的增加来解释。我们建议继续进行种群监测并采用此处介绍的采样协议和数据分析方法作为基线，以更好地了解丰度的时空变化。和 2018 年。过去 3 年丰度增加的事实可以用总初级生产力的增加来解释。我们建议继续进行种群监测并采用此处介绍的采样协议和数据分析方法作为基线，以更好地了解丰度的时空变化。