eDNA metabarcoding bioassessment of endangered fairy shrimp (Branchinecta spp.) - Part A

Fairy shrimp are integral components of vernal pool ecosystems, providing key food resources for migratory birds and amphibians. However, habitat degradation and land use change severely threaten the health of both vernal pools and the survival of fairy shrimp species. Branchinecta sandiegonensis has been particularly affected by urban and agricultural development in its small native range within San Diego County, California, USA. It is listed as an endangered species under both state and federal laws and is actively managed for its conservation. However, despite its legal protections, current methods of population assessment require the capture and sacrifice of individuals of B. sandiegonensis  in order to identify specimens to species level through microscopy. Furthermore, accurate species-level identification is especially important given overlap of B. sandiegonensis with a common (non-threatened) sister species, B. lindahli. Thus non-invasive methods to definitively distinguish thes...仙女虾（Fairy shrimp）是季节性池塘（vernal pool）生态系统中不可或缺的组成部分，为候鸟与两栖类提供关键食物资源。然而，栖息地退化与土地利用变化严重威胁着季节性池塘的生态健康，以及仙女虾物种的存续。其中，圣地亚哥仙女虾（Branchinecta sandiegonensis）的原生分布范围仅局限于美国加利福尼亚州圣迭戈县的狭小区域，受当地城市与农业开发的影响尤为严重。该物种已被州级与联邦法律列为濒危物种，并得到了积极的保护管理。尽管已有法律保护，但当前的种群评估方法仍需捕获并处死圣地亚哥仙女虾个体，通过显微镜观察以实现物种水平的标本鉴定。此外，鉴于圣地亚哥仙女虾与一种常见（非受威胁）的近缘物种林氏仙女虾（B. lindahli）存在形态重叠，准确的物种级鉴定显得尤为重要。因此，可精准区分二者的非侵入式鉴定方法