Field-ready DNA extraction from scat using magnetic nanoparticles for non-invasive wildlife monitoring.

Scat is commonly used to non-invasively monitor the presence of wildlife. Samples are typically collected in the field and transported to a laboratory for downstream DNA analysis. Current gold-standard extraction methods rely on column-based kits that are expensive, labor-intensive, and require specialized instrumentation. Here we present a rapid and low-cost DNA extraction method using silica-coated magnetic beads, tested on our species of interest - Rangifer tarandus (a Species at Risk currently monitored in Canada using scat sampling) and extended to other Cervidae species. This portable approach requires only simple equipment, yields stable DNA, and is well suited for polymerase chain reaction (PCR) analysis both in the field and in centralized laboratories. We also designed and validated novel primers specific for R. tarandus mitochondrial DNA to enable reliable species identification from scat. In this study, we demonstrate the ease of use, DNA yield, stability and PCR success of our method compared with widely used kits. We further show its applicability across additional Cervidae scat, underscoring its transferability to other herbivorous mammals.