Environmental DNA (eDNA)

Environmental DNA, or eDNA, refers to genetic material, skin cells, mucus, faeces, hair or other biological residue, that organisms continuously shed into their surrounding environment. Scientists can collect samples of soil, water or air and analyse the trace genetic material within them to determine which species are present in an area, without requiring a direct sighting, capture or invasive sampling of the organism itself. The method is a substantial advance for surveying cryptic, nocturnal, arboreal or otherwise hard-to-observe species, for which traditional survey methods such as camera trapping are structurally weak. Camera traps depend on an animal walking past a fixed point at ground level, precisely the behaviour that an arboreal, nocturnal or wide-ranging species is least likely to display, so eDNA sampling can establish presence in situations where camera-trap data would be sparse or absent. eDNA is typically used alongside other non-invasive methods, particularly occupancy surveys, which estimate the proportion of a landscape occupied by a species rather than an absolute population count, and are statistically more defensible than density estimates when the probability of detecting an individual is low. India's first dedicated Clouded Leopard Conservation Action Plan (2026) built its entire monitoring protocol around this combination, camera traps, occupancy surveys, genetic analysis and eDNA, precisely because reliable population baselines for the species had never existed, and setting numerical targets without such a baseline would have been scientifically indefensible.

• 1 eDNA = genetic material shed by an organism into soil, water or air, sampled to detect species presence without sighting or capture.
• 2 Especially valuable for cryptic, nocturnal or arboreal species poorly detected by camera traps.
• 3 Camera traps require an animal to pass a fixed ground-level point; eDNA does not depend on this behaviour.
• 4 Often paired with occupancy surveys (estimating the proportion of landscape occupied) rather than absolute density estimates.
• 5 Occupancy surveys are statistically more defensible than density estimates when detection probability is low.
• 6 Used in India's first Clouded Leopard Conservation Action Plan (2026) as part of a baseline-first monitoring protocol across 14 priority landscapes in Northeast India.
• 7 Represents a shift in conservation planning from setting population targets first to establishing a scientific baseline first.

India's Clouded Leopard Conservation Action Plan used eDNA alongside camera traps and occupancy surveys to establish a monitoring baseline for a species too nocturnal and arboreal to be reliably surveyed by conventional methods alone.