Smith-Root Sampling Equipment on the Cutting Edge of eDNA Research

Two new peer-reviewed studies published in 2026 demonstrate that Smith-Root’s environmental DNA (eDNA) sampling technology is at the forefront of aquatic species monitoring, delivering reliable, field-tested performance across diverse research applications. In the first, a prototype Smith-Root eDNA Autosampler autonomously tracked the migrations of adult Pacific salmon through Seattle’s Lake Washington Ship Canal, capturing behavioral patterns including a striking 23-day delay in Chinook migration. In the second, Smith-Root’s self-preserving filter housing was put through rigorous field testing across Pacific Northwest streams, where it matched ethanol-preserved filters in performance while dramatically outperforming older filtration methods. Both studies feature Smith-Root’s 5.0-μm self-preserving filter technology, and both involve co-author Austen C. Thomas of Smith-Root, Inc.

In a landmark study published in Frontiers in Ecology and Evolution (Hoy et al., 2026; https://doi.org/10.3389/fevo.2026.1824094), researchers from the U.S. Geological Survey’s Western Fisheries Research Center deployed a prototype Smith-Root eDNA Autosampler in Seattle’s Lake Washington Ship Canal to track the migrations of adult Chinook, Sockeye, and Coho salmon across a full four-month return season. Collecting samples autonomously twice daily, day and night, the autosampler captured the fine-scale movement of all three species with remarkable resolution, revealing species-specific migration lag times between fish counts at the Ballard Locks and eDNA detection 3 km upstream. For Sockeye and Coho, eDNA peaked just five days after visual fish counts, a result consistent with known transit times through the canal. Most strikingly, Chinook eDNA lagged visual counts by approximately 23 days, a pattern the authors attribute to the well-documented “recycling” behavior of Chinook holding in cold-water refuges near the locks during the warmest months of summer before pushing upstream once temperatures declined below 20°C. The autosampler performed comparably to manual sampling methods while delivering a level of temporal resolution that manual field collection simply cannot match, demonstrating its potential as a scalable, low-labor tool for long-term salmon migration surveillance.

A companion study published in Environmental DNA (Pilliod et al., 2025; https://doi.org/10.1002/edn3.70104) (Revised 2026) put Smith-Root’s self-preserving filter housing, the same filter technology used in the autosampler, through rigorous field testing in the streams of Washington state and British Columbia, where researchers sampled eDNA from free-swimming rainbow trout across a range of discharge and temperature conditions. The self-preserving filters performed comparably to identical filters preserved in ethanol, validating the desiccation-based preservation approach that makes autonomous and remote eDNA collection practical without the need for cold storage or chemical preservatives in the field. Notably, both the self-preserving and ethanol-preserved 5.0-μm PES filters significantly outperformed the traditional 0.45-μm cellulose nitrate filter protocol in DNA detection and yield, an important finding for the many monitoring programs currently using older methods. The study also raises a critical and underappreciated point: when monitoring programs switch sampling methods, formal calibration is essential to ensure that apparent changes in eDNA signal reflect real biological trends rather than methodological artifacts. Taken together, these two studies confirm that Smith-Root’s eDNA sampling technology is not only field-ready and effective, but is actively enabling the next generation of fish monitoring science.