Birds (Class Aves) are feathered, warm-blooded vertebrates that evolved from small theropod dinosaurs during the age of the dinosaurs. Modern birds are therefore the only living dinosaurs, with more than 11,000 species found across every continent and ocean.

They occupy an extraordinary range of ecological roles — from ocean-wandering albatrosses and forest canopy specialists to desert runners and aerial insect hunters. Advances in DNA research over the past two decades have greatly reshaped our understanding of bird relationships, revealing deep evolutionary connections between groups that were once thought unrelated.

How the Classification is Organised

The classification used here broadly follows the sequence of the  AviList 2025, arranged into nine sections that reflect major evolutionary groupings. Each section includes a short overview of the orders within it, followed by my personal records of species observed.

Section 1 — Ratites, Tinamous & Gamebirds

Early-branching ground birds with ancient lineages, including the flightless ratites and their flying relatives the tinamous, alongside the early waterfowl and gamebirds such as ducks, geese, pheasants, and grouse.

Section 2 — Flamingos to Pigeons

A diverse mix of wetland and land‑based birds, starting with flamingos and grebes and moving through turacos, bustards, cuckoos, and finally pigeons and doves. This group bridges aquatic specialists and mainly terrestrial or arboreal species.

Section 3 — Rails, Cranes & Shorebirds

Wetland and coastal birds ranging from secretive marsh species to coastal and oceanic shorebirds. This section includes rails, cranes, waders, gulls, and terns, many of which are long-distance migrants.

Section 4 — Seabirds & Large Aquatic Birds

Birds strongly adapted to aquatic life, including penguins, albatrosses, loons, cormorants, pelicans, herons, and storks. Many are specialised swimmers, divers, or long-distance ocean travellers.

Section 5 — Nocturnal & Aerial Insectivores

A group centred on birds adapted for catching insects in low light or in flight, including nightjars, potoos, swifts, and hummingbirds.

Section 6 — Owls & Birds of Prey

The main predatory birds, from nocturnal owls to diurnal raptors such as hawks, eagles, kites, and vultures. These species are adapted for hunting with sharp eyesight, strong talons, and powerful flight.

Section 7 — Rollers, Kingfishers & Woodpeckers

A colourful and mostly arboreal birds including trogons, hornbills, rollers, kingfishers, jacamars, puffbirds, and woodpeckers, many associated with forest and woodland habitats.

Section 8 — Falcons, Seriemas & Parrots

These evolutionarily linked but very different groups are the closest relatives of the songbirds: the fast-flying falcons, the ground-hunting seriemas, and the intelligent and highly social parrots.

Section 9 – Passerines (Perching Birds)

The largest and most diverse group of birds, making up over half of all species. Passerines range from ancient New Zealand wrens to broadbills, flycatchers, fairywrens, crows, warblers, thrushes, finches, and the many colourful families of the tropics.

Because of their size and evolutionary breadth, the passerines are presented here in six major subsections covering the full range of passerine diversity.

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Species lists reflect my personal observations, with notes on location and date where recorded. Photographs will be added progressively.

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Previous classification and comparison

When I first explored bird classification I found that the major global checklists didn’t agree on the orders, families or species recognised. To understand those differences, I compared the four leading world lists available at the time and created a table showing how each arranged the class Aves.

At the time, I used the BirdLife International (2018 v3) list for my own site, as it was the most practical to work with. BirdLife listed 36 orders, 242 families, and 10,943 species (excluding extinct species).

Since then, the global community has addressed this issue directly. In June 2025 the first version of AviList — a unified global checklist of birds — was published, providing a consensus global taxonomy developed by the major ornithological authorities. AviList aims to harmonise previously conflicting treatments and is now the standard reference I use for the classification on this site.