The avifauna of Ireland included a total of 522 species as of the end of 2019 according to the Irish Rare Birds Committee (IRBC).
Several species such as the tawny owl, Eurasian nuthatch and willow tit which breed in Great Britain have not been recorded.
However, there are large colonies of seabirds including important populations of European storm-petrels, northern gannets, and roseate terns.
This list's taxonomic treatment (designation and sequence of orders, families and species) and nomenclature (English and scientific names) are those of the International Ornithological Congress (IOC) as of July 2021.
These birds are adapted to an aquatic existence with webbed feet, flattened bills, and feathers that are excellent at shedding water due to an oily coating.
Order: Otidiformes Family: Otididae Bustards are large terrestrial birds mainly associated with dry open country and steppes in the Old World.
Order: Pterocliformes Family: Pteroclidae Sandgrouse have small, pigeon-like heads and necks, but sturdy compact bodies.
Order: Charadriiformes Family: Burhinidae The thick-knees are a group of waders found worldwide within the tropical zone, with some species also breeding in temperate Europe and Australia.
Order: Charadriiformes Family: Haematopodidae The oystercatchers are large and noisy plover-like birds, with strong bills used for smashing or prising open molluscs.
They are small to medium-sized birds with compact bodies, short thick necks, and long, usually pointed, wings.
Variation in length of legs and bills enables multiple species to feed in the same habitat, particularly on the coast, without direct competition for food.
Terns are a group of generally medium to large seabirds typically with grey or white plumage, often with black markings on the head.
Order: Charadriiformes Family: Alcidae Alcids are superficially similar to penguins due to their black-and-white colours, their upright posture, and some of their habits.
Order: Gaviiformes Family: Gaviidae Loons, also known as divers, are a group of aquatic birds found in many parts of North America and northern Europe.
Order: Procellariiformes Family: Procellariidae The procellariids are the main group of medium-sized "true petrels", characterised by united nostrils with medium septum and a long outer functional primary.
Order: Ciconiiformes Family: Ciconiidae Storks are large, long-legged, long-necked, wading birds with long, stout bills.
Members of Ardeidae fly with their necks retracted, unlike other long-necked birds such as storks, ibises, and spoonbills.
Order: Strigiformes Family: Strigidae The typical owls are small to large solitary nocturnal birds of prey.
Order: Bucerotiformes Family: Upupidae Hoopoes have black, white, and orangey-pink colouring with a large erectile crest on their head.
Order: Coraciiformes Family: Coraciidae Rollers resemble crows in size and build, but are more closely related to the kingfishers and bee-eaters.
Order: Coraciiformes Family: Alcedinidae Kingfishers are medium-sized birds with large heads, long pointed bills, short legs, and stubby tails.
Order: Piciformes Family: Picidae Woodpeckers are small to medium-sized birds with chisel-like beaks, short legs, stiff tails, and long tongues used for capturing insects.
Order: Passeriformes Family: Vireonidae The vireos are a group of small to medium-sized passerine birds restricted to the New World.
Order: Passeriformes Family: Bombycillidae The waxwings are a group of birds with soft silky plumage and unique red tips to some of the wing feathers.
Order: Passeriformes Family: Remizidae The penduline-tits are a group of small passerine birds related to the true tits.
Order: Passeriformes Family: Alaudidae Larks are small terrestrial birds with often extravagant songs and display flights.
Order: Passeriformes Family: Aegithalidae Long-tailed tits are a group of small passerine birds with medium to long tails.
They are generally very small birds of drab brown or grey appearance found in open country such as grassland or scrub.
They mainly occur as breeding species, as another common name (Old World warblers) implies, in Europe, Asia, and, to a lesser extent, Africa.
Order: Passeriformes Family: Cinclidae Dippers are a group of perching birds whose habitat includes aquatic environments in the Americas, Europe, and Asia.