We develop a new method for estimating population abundance for notoriously difficult to count populations. This is made possible using an easy to count auxiliary population with a known link to the target population under the framework of a layered hidden Markov model. We apply the new methods to estimate the breeding population of an Ancient Murrelet seabird colony, using Ancient Murrelet chicks as an auxiliary population. We compare our results to those of the established survey methodology from the Canadian Wildlife Service (CWS), which similarly shows a decrease in population over 1995 to 2006. Our methods improve upon the CWS survey methods by allowing density differences across sampling sites, and by allowing estimates to be made between CWS survey years.

中文翻译：

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使用辅助人口计数估算人口数量

我们开发了一种新方法，用于估计难以计数的人口数量。在分层的隐马尔可夫模型的框架下，使用易于计数的辅助人口（与目标人口的已知链接）可以实现这一点。我们应用新方法，以古默雷莱特小鸡为辅助种群，估算古默雷莱特海鸟殖民地的繁殖种群。我们将结果与加拿大野生动物服务局（CWS）建立的调查方法的结果进行比较，该方法类似地显示了1995年至2006年间种群数量的减少。我们的方法通过允许各个采样点之间的密度差异以及允许在CWS调查年之间进行估算。