Humans have caused the extinction of many bird species around the world. Since the 1500s, over 190 species of birds have gone extinct due to human activity. The main causes have been overhunting, habitat loss and introduction of invasive species. This article will look at some of the bird species made extinct by humans and the reasons why.
Why Do Humans Cause Bird Extinctions?
There are several ways that human activity has led to bird extinctions over the past few centuries:
- Hunting and trapping – Humans have hunted birds for food, feathers and sport. This includes hunting adult birds as well as collecting eggs and chicks from nests.
- Habitat loss – Deforestation, urbanization, agriculture and other human land uses have destroyed natural habitats for birds around the world.
- Invasive species – Humans have introduced predators like rats and cats as well as diseases that have wiped out native bird populations on islands.
- Pollution – Pesticides, oil spills and other forms of pollution have poisoned birds and their food sources.
Birds are particularly vulnerable to these threats for several reasons. Many species naturally exist in small, isolated populations that are easily decimated. They also reproduce slowly relative to other animals. Once bird populations drop below a viable level, the chance of extinction dramatically rises.
Extinct Birds in North America
At least 62 bird species have gone extinct in North America since 1500. Here are some of the notable extinctions:
- Carolina parakeet – This brightly colored parrot was once found across the southeastern US. Forest clearance and hunting drove the species to extinction by the early 1900s.
- Passenger pigeon – These pigeons used to number in the billions, forming massive migratory flocks across eastern North America. Overhunting reduced them to extinction by 1914.
- Labrador duck – A striking black and white sea duck that bred along the northeastern US and Canadian coasts until about 1875. Hunting and egg collection led to its demise.
- Great auk – This large flightless seabird bred on islands off northeastern North America. Overhunting of the great auk for its meat, eggs and feathers caused extinction by the mid-1800s.
Causes of North American Bird Extinctions
Most North American bird extinctions over the past 500 years have been caused by:
- Hunting by early European colonists and settlers who didn’t realize how fragile bird populations were.
- Widespread habitat loss as forests were cleared for agriculture and cities.
- Nest harvesting and egg collecting.
- Introduction of non-native predators like rats and cats to islands.
Laws banning excessive hunting and egg collecting came too late to save many species that were already in severe decline by the late 1800s and early 1900s.
Extinct Birds in Hawaii
The Hawaiian Islands were once home to over 140 native bird species. At least 71 species have gone extinct since Polynesians and Europeans arrived in Hawaii. Examples include:
- Hawaiian rail – Abundant water birds hunted to extinction by the late 1800s.
- Kona grosbeak – A colorful finch-like bird last seen in the 1890s, likely wiped out by deforestation and disease.
- Oahu oo – A type of Hawaiian honeyeater last recorded in 1934 and driven to extinction by habitat loss and introduced predators.
Causes of Hawaiian Bird Extinctions
The main causes of mass bird extinctions in Hawaii include:
- Hunting – Native Hawaiians hunted many forest bird species for their colorful feathers.
- Deforestation – Logging of koa and other trees removed forest habitat.
- Invasive species – Rats, cats, pigs and other non-native animals preyed upon native birds and destroyed nests.
- Disease – Avian malaria spread by introduced mosquitoes ravaged Hawaiian honeycreeper populations.
Extinct Birds Elsewhere in the World
Bird extinctions caused by humans have occurred on nearly every continent. Some other notable examples include:
- Moa – Giant flightless birds of New Zealand hunted to extinction by 1500.
- Elephant bird – Huge, 1000-pound flightless birds driven to extinction on Madagascar by 1700.
- Laughing owl – A unique owl species exterminated in New Zealand by invasive predators in the 1900s.
- Stephens Island wren – The only flightless songbird in the world, wiped out by a single cat in 1895!
- Ivory-billed woodpecker – This majestic woodpecker native to the southeastern US is now critically endangered and likely extinct.
Global Causes of Bird Extinctions
On a global scale, the leading causes of human-driven bird extinction include:
- Habitat destruction from deforestation, agriculture and urban sprawl.
- Overexploitation from hunting and egg harvesting.
- Invasive species preying on native birds and destroying nests.
- Disease outbreaks enabled by human transport and encroachment.
Island species have been especially vulnerable, but extinctions have occurred on all continents and habitats. Conservation measures have slowed extinctions in recent decades, but many species remain critically endangered.
Recently Extinct Bird Species
While the main wave of human-driven extinctions occurred prior to the 20th century, some birds have become extinct more recently. Here are some of the most recent probable or confirmed extinctions:
| Species | Location | Year Extinct | Cause of Extinction |
|---|---|---|---|
| Spix’s Macaw | Brazil | 2000 | Trapping for wild bird trade |
| Poo-uli | Hawaii | 2004 | Habitat loss, invasive predators |
| Alaotra Grebe | Madagascar | 2010 | Habitat degradation, predation by carnivorous fish |
| Po’ouli | Hawaii | 2004 | Habitat loss, invasive predators, lack of mates |
These examples reflect more modern threats like illegal wildlife trade as well as ongoing habitat loss and invasive species. Several other bird species have not been seen for decades and are likely extinct, though not officially declared so yet.
Preventing Further Bird Extinctions
To prevent future human-caused bird extinctions, conservationists recommend:
- Habitat protection – Preserve rainforests, wetlands and other natural ecosystems.
- Managed reintroductions – Carefully reintroduce endangered species to suitable habitat.
- Control of invasive species – Remove introduced rats, cats, pigs and other predators.
- Limits on pet trade – Ban or limit wild bird trafficking, a major threat to rare parrots.
- Public awareness – Promote appreciation and support for endangered birds.
Targeted conservation programs have saved species like the California condor from likely extinction. But continued effort and vigilance will be needed to prevent further losses of the world’s most vulnerable birds.
Conclusion
Human activity over the past centuries has driven numerous bird species to extinction around the globe. Overhunting was a major historical cause, while habitat loss, invasive species and pollution continue to threaten birds today. North America, Hawaii and other Pacific islands were hit especially hard, with well over 100 species lost. Conservation efforts have slowed bird extinctions in recent decades, but many more species face a precarious future unless critical habitat can be preserved in the face of growing human impacts worldwide.
