Meeting Abstract
Environmental DNA (eDNA) assays have become a major aspect of amphibian surveys in the past decade. These methods are highly sensitive making them well-suited for monitoring rare and elusive species. Current efforts to study the Rio Grande siren in the Lower Rio Grande Valley (LRGV) have been hampered due to the cryptic nature of these aquatic salamanders. Arid conditions in the LRGV further add to the difficulty in studying this species, as many water bodies they inhabit are ephemeral, constraining sampling efforts to a short window after heavy deluges. Additionally, sirens are known to cease activity and reside underground when breeding ponds are dry. Conventional sampling efforts are require extensive man-hours to be effective, which is not always possible within the required sampling window. We here discuss the development of a novel eDNA assay technique for this elusive species quantified via probe-based qPCR. This study has found a small, handheld, coffee filtration apparatus to be a viable replacement for small-pore filters and bulky vacuum pumps, which are not capable of filtering the large amounts of turbid water required for siren detection. This methodology holds great promise for the assessment of Rio Grande sirens in the LRGV and for potential adaption to other south Texas amphibians also breeding in these highly turbid water bodies.
