Over 200 vascular plant species have been recorded at Abernethy NNR, including some nationally scarce species like twinflower and creeping lady's tresses. Heath cudweed is also present in the reserve, classed as an endangered species. The NNR also supports a diverse population of birds, with over 70 species recorded at the Reserve. These include the Scottish crossbill, crested tit and capercaillie, which are all relatively rare species in Britain. Other birds present at the Reserve include buzzards, tawny owls, great spotted woodpeckers and sparrowhawks. A variety of mammals have also been recorded at the reserve, including red and roe deer; red squirrels; common pipistrelles; more elusive otters and pine martens; and possible sightings of wildcats. NatureScot has reported fourteen species of butterfly at the Reserve, including the pearl-bordered fritillary, a UK Biodiversity Action Plan species.