Shrinking saline lakes provide irreplaceable habitat for waterbird species globally. Disentangling the effects of wetland habitat loss from other drivers of waterbird population dynamics is critical for protecting these species in the face of unprecedented changes to saline lake ecosystems, ideally through decision‐making frameworks that identify effective management options and their potential outcomes. Here, we develop a framework to assess the effects of hypothesized population drivers and identify potential future outcomes of plausible management scenarios on a saline lake‐reliant waterbird species. We use 36 years of monitoring data to quantify the effects of environmental conditions on the population size of a regionally important breeding colony of American white pelicans (Pelecanus erythrorhynchos) at Great Salt Lake, Utah, US, then forecast colony abundance under various management scenarios. We found that low lake levels, which allow terrestrial predators access to the colony, are probable drivers of recent colony declines. Without local management efforts, we predicted colony abundance could likely decline approximately 37.3% by 2040, although recent colony observations suggest population declines may be more extreme than predicted. Results from our population projection scenarios suggested that proactive approaches to preventing predator colony access and reversing saline lake declines are crucial for the persistence of the Great Salt Lake pelican colony. Increasing wetland habitat and preventing predator access to the colony together provided the most effective protection, increasing abundance 145.4% above projections where no management actions are taken, according to our population projection scenarios. Given the importance of water levels to the persistence of island‐nesting colonial species, proactive approaches to reversing saline lake declines could likely benefit pelicans as well as other avian species reliant on these unique ecosystems.

中文翻译：

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依赖规模的种群驱动因素为咸水湖生态系统中的鸟类管理提供信息


萎缩的盐湖为全球水鸟物种提供了不可替代的栖息地。面对咸水湖生态系统前所未有的变化，将湿地栖息地丧失的影响与水鸟种群动态的其他驱动因素区分开来，对于保护这些物种至关重要，最好是通过确定有效管理方案及其潜在结果的决策框架。在这里，我们开发了一个框架来评估假设的种群驱动因素的影响，并确定合理的管理方案对依赖盐湖的水鸟物种的潜在未来结果。我们使用 36 年的监测数据来量化环境条件对美国犹他州大盐湖区具有区域重要性的美国白鹈鹕 （Pelecanus erythrorhynchos） 繁殖群规模的影响，然后预测各种管理情景下的蚁群丰度。我们发现，允许陆生捕食者进入栖息地的低湖水位可能是最近栖息地数量下降的驱动因素。如果没有当地的管理努力，我们预测到 2040 年，蜂群丰度可能会下降约 37.3%，尽管最近的蜂群观察表明种群下降可能比预测的更极端。我们的种群预测情景的结果表明，防止捕食者群落进入和逆转盐湖下降的积极方法对于大盐湖鹈鹕群落的持续存在至关重要。根据我们的种群预测情景，增加湿地栖息地和防止捕食者进入栖息地共同提供了最有效的保护，比未采取管理行动的预测增加了 145.4%。 鉴于水位对岛屿筑巢殖民物种的持续存在的重要性，扭转盐湖下降的积极方法可能会使鹈鹕以及依赖这些独特生态系统的其他鸟类物种受益。