Total | Amphibians | Birds | Fish | Mammals | Reptiles | Vascular Plants

Total number of bird species, by country

Note, this data from Birdlife International was last updated December 26, 2023

Source: Plant data is from the World Conservation Monitoring Centre of the United Nations Environment Programme (UNEP-WCMC), 2004. Species Data. Fish: Fishbase; Birds: Birdlife International; Amphibians: AmphibiaWeb; Mammals: IUCN; Reptiles: the Reptile Database.

Total | Amphibians | Birds | Mammals | Reptiles | Vascular Plants

A World in Flight: Patterns of Bird Diversity Across the Planet

With more than 10,000 species spread across the globe, birds are one of the most diverse and ecologically significant animal groups on Earth. They range from the iridescent hummingbirds of the Amazon to the snow-dwelling ptarmigans of the Arctic, filling nearly every available ecological niche. Yet, their diversity is far from evenly distributed. The planet’s richest avian assemblages are concentrated in the tropical rainforests of South America, Africa, and Southeast Asia, while the high latitudes and arid regions host comparatively fewer species. This geographic variation in bird diversity is shaped by climate, habitat complexity, evolutionary history, and biogeography, revealing distinct patterns across continents.

The Bird Supercontinent: South America’s Extraordinary Richness

South America is the undisputed epicenter of bird diversity, home to five of the ten most bird-rich countries. Colombia, with an astonishing 1,917 species, leads the world, followed closely by Peru (1,892), Brazil (1,864), Ecuador (1,684), and Bolivia (1,446).

The sheer diversity of birds in the Neotropics is a direct result of habitat complexity—from the Andean cloud forests, where multiple elevational bands create distinct ecological communities, to the Amazon rainforest, where a single hectare can support hundreds of bird species. The presence of the Amazon River Basin, the world’s largest tropical rainforest, has acted as a cradle for avian speciation, providing a vast, uninterrupted expanse of habitat where species have diversified over millions of years.

Among the most striking South American birds are the toucans, parrots, and hummingbirds, each group displaying extraordinary adaptations to their environment. Toucans, with their massive, lightweight bills, serve as fruit dispersers, while hummingbirds, the most diverse in South America, exhibit remarkable aerial agility and metabolic adaptations. The region is also home to some of the planet’s rarest and most enigmatic birds, including the resplendent quetzal of Central America and the hoatzin, a bird with a digestive system that resembles that of ruminant mammals.

In the Amazon and Andean foothills, mixed-species foraging flocks form a fascinating ecological phenomenon, where tanagers, antbirds, woodcreepers, and flycatchers move together, reducing predation risk and maximizing foraging efficiency. Such complex interspecies interactions contribute to the immense avian richness of the region.

Southeast Asia and the Archipelagic Effect

The island-studded landscapes of Southeast Asia and the Indo-Pacific create another hotspot of bird diversity, best exemplified by Indonesia, which harbors 1,791 bird species—the highest number of any country outside the Americas. The fragmentation of habitats across islands has led to an extraordinary degree of endemism, with species found nowhere else in the world.

The birds-of-paradise in New Guinea, for example, have evolved elaborate courtship displays that are unparalleled in the avian world, while the hornbills of Sumatra, Borneo, and the Philippines play a crucial role in seed dispersal, effectively regenerating rainforests. Indonesia’s bird diversity also extends to coastal and marine environments, with thousands of islands providing breeding grounds for seabirds and wading birds, including terns, frigatebirds, and pelicans.

One of the most intriguing patterns in Southeast Asian bird diversity is the Wallace Line, a biogeographical boundary separating the faunal regions of Asia and Australasia. West of the line, birds resemble those of the Asian mainland, including pheasants, bulbuls, and babblers, whereas east of the line, species share affinities with Australian avifauna, such as cockatoos, honeyeaters, and megapodes.

Africa: Ancient Rainforests and Open Savannas

Africa, the continent where modern birds first evolved, supports a unique and ancient avian assemblage. While the Democratic Republic of Congo (1,155 species) holds the continent’s highest bird diversity, it is the mosaic of habitats—ranging from the rainforests of the Congo Basin to the dry acacia woodlands and savannas—that shapes bird distribution across Africa.

The Congo Basin, the world’s second-largest rainforest, is home to colorful turacos, elusive forest kingfishers, and melodious greenbuls. In contrast, the open landscapes of East and Southern Africa support some of the most iconic birds on Earth, including ostriches, secretary birds, and various raptors. Africa is also renowned for its migratory corridors, where European and Asian birds winter in the continent’s wetlands, woodlands, and grasslands.

A distinctive feature of African avian ecology is the prevalence of cooperative breeding, seen in species like the southern ground hornbill and the superb starling, where groups of individuals assist in raising young. The continent also hosts honeyguides, birds uniquely adapted to leading humans and other animals to beehives in exchange for access to beeswax and larvae.

The Bird Divide: Contrasting Diversity in Asia and the Northern Hemisphere Asia, while home to biodiversity hotspots such as the Himalayas, the Sundaland forests, and the Tibetan Plateau, has fewer bird species per unit area compared to the tropics of South America and Africa. China (1,330 species) and India (1,271 species) lead the region in total bird diversity, with landscapes ranging from tropical forests to alpine meadows.

The Himalayas, the tallest mountain range in the world, serve as a barrier and corridor for bird migration, creating vertical gradients of species richness. This phenomenon is reflected in high-altitude specialists such as the snow partridge and Himalayan monal, while the lowland forests of Northeast India and Yunnan support a remarkable variety of hornbills, pittas, and pheasants.

Unlike the tropical rainforests, where bird diversity remains high year-round, the temperate and boreal forests of the Northern Hemisphere experience pronounced seasonal fluctuations. In regions like Siberia, Canada, and Scandinavia, many species are highly migratory, moving south in winter and returning north for the explosion of insect life in summer.

Conclusions: A Planet Shaped by Wings

The global distribution of bird diversity is shaped by millions of years of evolutionary history, climatic stability, and ecological interactions. The tropics, particularly South America and Southeast Asia, remain the planet’s richest avian regions, while isolation and altitude shape unique species assemblages. Meanwhile, birds continue to face threats from deforestation, habitat fragmentation, and climate change, making conservation efforts more critical than ever.

Yet, despite the challenges, birds remain one of the most adaptable life forms, navigating landscapes that range from dense equatorial forests to polar ice caps. Whether soaring above the Amazon, gliding through Indonesian islands, or weathering the Himalayan winds, their patterns of diversity reveal the incredible resilience and complexity of life on Earth.

More reading

• Rainforest canopy birds
• Rainforest floor birds
• Recent news about birds