It has some welcome visitors from the wild bird community, the red kite, peregrine falcon, chough and stonechat are some of the species to be found in the locality.
Stonechats, willow warblers and wood warblers sing from perches just off the path but the robins and chaffinches are far bolder and will hop around the path just two feet away from human visitors.
A number of rare plant, animal, bird and insect species can be found on the heathland including: Butterflies (e.g. Small Heath and Green Hairstreak), grasshoppers, Common lizards, Skylarks, and Stonechats.
It is a small bird 11.5–13 cm long, very closely similar to the Siberian Stonechat in both plumage and behaviour, differing in only small details, notably having a slightly broader-based bill 4.7–5.7 mm wide (4.0–4.9 mm wide in Siberian Stonechat) and slightly less white on the rump.
Trefil Quarries and Trefil Ddu are noted birding sites; this area is the last remaining site in Gwent where Ring Ouzel occurs regularly, and other species present include Raven, Wheatear, Stonechat, Whinchat, Snipe and Red Grouse.