Estimates of age-specific survival probabilities are needed for age-structured population models and to inform conservation decisions. However, determining the age of individuals in wildlife populations is often problematic. We present a hidden Markov model for estimating age-specific survival from capture–recapture or capture–recapture–recovery data when age is unknown and indicators of age, such as size and growth layer counts, are imprecise. The model is evaluated through simulations, and its implementation is illustrated with maximum likelihood and Bayesian approaches in commonly used software. The model is then applied to genetic capture–recapture data of Florida manatees to estimate age- and time-variant survival probabilities. The approach is broadly applicable to studies aiming to quantify age-specific effects of environmental change and management actions on population dynamics, including studies that rely on minimally invasive methods such as genetic and photo identification.

中文翻译：

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当年龄和大小不确定时，用于估计特定年龄生存的隐马尔可夫模型

年龄结构人口模型需要对特定年龄的生存概率进行估计，并为保护决策提供信息。然而，确定野生动物种群中个体的年龄通常是有问题的。我们提出了一个隐马尔可夫模型，用于在年龄未知且年龄指标（例如大小和生长层计数）不精确时，从捕获-重新捕获或捕获-重新捕获-恢复数据中估计特定年龄的存活率。该模型通过模拟进行评估，并在常用软件中用最大似然和贝叶斯方法说明其实现。然后将该模型应用于佛罗里达海牛的遗传捕获-重新捕获数据，以估计随年龄和时间变化的生存概率。