Lien vers Pubmed [PMID] – 37313847
Lien DOI – 10.24272/j.issn.2095-8137.2022.481
Zool Res 2023 Jul; 44(4): 701-711
The sizes of Astyanax mexicanus blind cavefish populations of North-East Mexico are demographic parameters of great importance for investigating a variety of ecological, evolutionary, and conservation issues. However, few estimates have been obtained. For these mobile animals living in an environment difficult to explore as a whole, methods based on capture-mark-recapture are appropriate, but their feasibility and interpretation of results depend on several assumptions that must be carefully examined. Here, we provide evidence that minimally invasive genetic identification from captures at different time intervals (three days and three years) can give insights into cavefish population size dynamics as well as other important demographic parameters of interest. We also provide tools to calibrate sampling and genotyping efforts necessary to reach a given level of precision. Our results suggest that the El Pachón cave population is currently very small, of an order of magnitude of a few hundreds of individuals, and is distributed in a relatively isolated area. The probable decline in population size in the El Pachón cave since the last census in 1971 raises serious conservation issues.分布于墨西哥东北部的墨西哥脂鲤洞穴盲鱼的种群规模是研究生态、进化和保护等问题的重要参数。然而，目前所获得的种群数量估计数据甚少。对于这些生活在难以整体探索的环境中的移动性的动物类群，基于捕获-标记-重新捕获的方法是合适的，但这种方法的可行性和对结果的解释取决于几个必须仔细研究的假设。在此，我们提供证据表明，从不同时间间隔（3天和3年）的捕获个体中进行微创遗传鉴定，可以深入了解洞穴鱼种群规模动态以及其他重要的种群统计参数。我们还提供了校准采样和基因分型工作所需的工具，以达到一定的精度水平。我们的研究结果表明，墨西哥脂鲤El Pachón洞穴种群目前非常小，数量级为几百个个体，并且分布在一个相对孤立的地区。自1971年普查以来， El Pachón 洞穴鱼种群规模的下降引发了严重的保护问题。