The birds of Tireragan are an almost unique avian assemblage with representatives of almost every ecosystem found in Scotland.
With few mammalian predator species found on the Scottish islands, bird species make up most of the top level predators in Tireragan. Raptors known to use the estate as a prey resource include golden eagles, merlin, hen harrier, kestrel, peregrine falcon, buzzard, sparrowhawk and short-eared owl.
Since the project started numbers of breeding merlin, hen harriers and short-eared owls have all increased in the estate and the golden eagles that utilise the area for prey have enjoyed breeding success well above the national average, largely down to the healthy population of mountain hare.
Along the coast, ravens constantly patrol the shore while ringed plover and oystercatcher breed on and around the beaches. On the more inaccessible sea cliffs shag nest in small colonies and rock pipits scuttle around the huge granite boulders.
The woodlands are home to increasing numbers of woodland and woodland edge species such as willow warbler, sedge warbler and whitethroat and equally healthy are the species found on the heath and moorland such as meadow pipit, twite, wheatear, cuckoo and red grouse.