Building Field-Ready Environmental RNA Panels

Environmental RNA (eRNA) has been increasingly used to move beyond 'who is there' toward 'who is active' and 'what is happening' in ecosystems. Yet, most workflows have been optimised for laboratory sequencing, and decision-grade field use has remained sporadic. In this article, field-ready eRNA panels are defined as curated sets of transcripts paired with process controls and a transparent scoring rule, and a build-test pathway is described from marker discovery to deployment. Candidate markers are prioritised with field constraints in mind (abundance, specificity, persistence, and confounding seasonality), and RNA class choice (mRNA, rRNA, small, and other non-coding RNAs) is treated as a design lever for robustness. Pre-analytics are discussed as panel engineering, with emphasis placed on capture, rapid stabilisation, and inhibitor management to preserve multi-marker relationships. Field readout options are then compared, including isothermal amplification, CRISPR-assisted detection, portable qPCR, and portable nanopore sequencing for on-site verification and panel refresh. Finally, minimum controls and staged validation levels are proposed to support defensible ecological claims. Deliberate attention is directed toward shared terminology and testable standards so that discussion within and between ecology, diagnostics, and conservation practice is stimulated and priorities for future investigations are sharpened.