Norway rats (Rattus norvegicus) living in urban environments are a critical public health and economic problem, particularly in urban slums where residents are at a higher risk for rat borne diseases, yet convenient methods to quantitatively assess population sizes are lacking. We evaluated track plates as a method to determine rat distribution and relative abundance in a complex urban slum environment by correlating the presence and intensity of rat-specific marks on track plates with findings from rat infestation surveys and trapping of rats to population exhaustion. To integrate the zero-inflated track plate data we developed a two-component mixture model with one binary and one censored continuous component. Track plate mark-intensity was highly correlated with signs of rodent infestation (all coefficients between 0.61 and 0.79 and all p-values < 0.05). Moreover, the mean level of pre-trapping rat-mark intensity on plates was significantly associated with the number of rats captured subsequently (Odds ratio1.38; 95 % CI 1.19–1.61) and declined significantly following trapping (Odds ratio 0.86; 95 % CI 0.78–0.95). Track plates provided robust proxy measurements of rat abundance and distribution and detected rat presence even when populations appeared ‘trapped out’. Tracking plates are relatively easy and inexpensive methods that can be used to intensively sample settings such as urban slums, where traditional trapping or mark-recapture studies are impossible to implement, and therefore the results can inform and assess the impact of targeted urban rodent control campaigns.

中文翻译：

---

对轨道板进行比较评估，以量化城市贫民窟中挪威老鼠相对丰度的精细尺度变化。


生活在城市环境中的挪威鼠（ Rattusnorvegicus ）是一个严重的公共卫生和经济问题，特别是在城市贫民窟，那里的居民患鼠传疾病的风险较高，但缺乏定量评估种群规模的便捷方法。我们将轨道板作为确定复杂城市贫民窟环境中老鼠分布和相对丰度的方法进行了评估，方法是将轨道板上老鼠特异性标记的存在和强度与老鼠侵扰调查和老鼠诱捕与人口枯竭的结果相关联。为了整合零膨胀轨道板数据，我们开发了一种双成分混合模型，其中一个二元成分和一个删失连续成分。轨道板标记强度与啮齿动物侵扰的迹象高度相关（所有系数在 0.61 和 0.79 之间，所有p值< 0.05）。此外，诱捕前板上大鼠标记强度的平均水平与随后捕获的大鼠数量显着相关（优势比 1.38；95% CI 1.19–1.61），并在诱捕后显着下降（优势比 0.86；95%） CI 0.78–0.95）。轨道板提供了对老鼠丰度和分布的可靠替代测量，即使在老鼠群体出现“被困”的情况下也能检测到老鼠的存在。追踪板是相对简单且廉价的方法，可用于对城市贫民窟等环境进行密集采样，在这些环境中传统的诱捕或标记重新捕获研究无法实施，因此结果可以为有针对性的城市啮齿动物控制活动提供信息和评估其影响。