The house finch (Haemorhous mexicanus) is a small songbird native to western North America that has been introduced to the eastern United States and Hawaii. Its natural range extends from southern British Columbia in Canada to central Mexico. Here is a quick overview of the house finch’s geographic range:
Native Range
The house finch is native to western North America, ranging from southern British Columbia in Canada south through the western United States to central Mexico. Its native range includes:
- British Columbia in Canada
- Washington, Oregon, California, Idaho, Nevada, Utah, Arizona, New Mexico in the western United States
- Western Texas
- Northern Baja California and Sonora in Mexico
Within this broad geographic range, house finches occupy a variety of open habitats including urban and suburban areas, arid deserts, grasslands, chaparral, and agricultural fields. They are found at elevations ranging from sea level to over 9,000 feet.
Introduced Eastern Range
House finches were introduced to the eastern United States in the 1940s when a small number of captive birds were released on Long Island, New York. This introduced population rapidly grew and expanded its range across the eastern United States and Canada. The house finch is now found across the eastern United States from Maine to Florida, and inland to the Great Plains from North Dakota to Texas.
It has also been introduced to Hawaii, first being recorded there in the 1870s. So in addition to its native western range, the house finch can now be found in the eastern half of the continental U.S. as well as Hawaii.
Range Expansion
Since being introduced to the eastern U.S. in the 1940s, the house finch has undergone a remarkably rapid range expansion across North America. Within just 50 years after its initial introduction, it occupied most of the eastern half of the continent from coast to coast.
Several factors contributed to the house finch’s successful introduction and establishment in the eastern U.S.:
- Ability to adapt well to human-altered habitats like suburbs, parks, and agricultural areas
- High reproductive rate, with frequent nesting and large clutch sizes
- Lack of major predators, parasites, or diseases in their introduced eastern range
Their geographic range continues to expand in North America, with populations being reported in new areas of the southeastern and central United States as recently as the 1990s and 2000s. Models suggest the house finch may continue spreading into unoccupied regions of the eastern U.S. and southern Canada.
Range Map
Here is a map showing the current known range of the house finch in North America:
Image source: Cornell Lab of Ornithology |
Key points about house finch range visible on the map:
- Native western range along the Pacific Coast and in the Southwest
- Introduced range occupying eastern and central United States
- Also introduced to Hawaii
Habitat
House finches occupy a variety of open habitats within their expansive geographic range across western and eastern North America. Their habitats include:
Human-Altered Landscapes
House finches readily thrive in human-modified environments and are common in areas like suburbs, parks, gardens, and agricultural areas. They often nest and forage near buildings and human developments.
Arid & Semi-Arid Regions
Much of the house finch’s western United States range includes hot, arid deserts and scrublands. They are found in desert habitats such as saguaros in the Sonoran Desert.
Open Woodlands
House finches occupy open, sparse pine-oak woodlands, chaparral, and other open forests and scrublands within their native western range.
Pacific Coast
Along the Pacific Coast they inhabit natural vegetation as well as urban and suburban developments within coastal cities.
Agricultural Areas
House finches will readily forage in agricultural areas including fields, orchards, and pastures, often feeding on seeds from crops and grasses.
Elevation
House finches can be found at elevations ranging from sea level along the Pacific Coast up to over 9,000 feet in mountainous areas of the western United States.
Population Status
The house finch is classified as a species of Least Concern according to the IUCN Red List. This indicates it is not considered at risk of extinction thanks to its extremely large and widespread population. Key population facts:
- Global population estimated at >300 million individuals
- Native western populations estimated at 140 million
- Introduced eastern populations at 160 million and growing
- Considered one of the most numerous and widespread bird species in North America
House finch populations in their native western range have seen declines of 25-60% in recent decades. However, the large introduced eastern population remains productive and continues to expand. Overall the house finch is abundant and its population remains secure.
Threats
House finch populations face a number of threats across their range:
Disease
A severe outbreak of conjunctivitis beginning in 1994 caused significant declines in eastern house finch populations. Western populations have also been impacted by the disease but to a lesser degree. It remains an ongoing threat.
Predators
Common house finch nest predators include snakes, cats, squirrels, and birds of prey. Predation pressure is higher in the finch’s native western range compared to human-dominated eastern regions.
Human Activities
House finches in urban areas face threats from building collisions and auto traffic. Use of pesticides reduces insect food supplies in some agricultural areas. But they thrive near human development in many areas.
Climate Change
Ongoing drought, wildfires, and other climate change impacts may threaten house finch populations in the arid western United States portion of their range.
Behavior
House finches display some key behavioral traits and adaptations across their range:
Social and Gregarious
House finches form large flocks outside of breeding season and are highly social even during nesting. Flocks voice constant contact calls.
Varied Vocalizations
They produce a wide range of vocalizations and singing is used in courtship. Regional dialects in songs have been observed.
Opportunistic Foragers
They forage opportunistically on a wide variety of seeds, fruits, and insects. This varied diet likely aids their ability to thrive in diverse habitats.
Rapid Reproduction
House finches breed frequently with multiple broods per year. Their reproductive output is among the highest of North American songbirds.
Semicolonial Nesting
Nesting birds are somewhat colonial, with nests aggregated in prime habitat. This aids range expansion and local population growth.
Tamed and Tolerant of Humans
Often tame and tolerant of human disturbance, they readily inhabit urban and suburban areas and have expanded with human settlement.
Taxonomy
The house finch has the following scientific classification:
- Kingdom: Animalia
- Phylum: Chordata
- Class: Aves
- Order: Passeriformes
- Family: Fringillidae
- Genus: Haemorhous
- Species: H. mexicanus
There are no recognized subspecies. Some authorities previously considered the house finch conspecific with the purple finch, placing them in the single species Carpodacus mexicanus.
Conclusion
In summary, the house finch is a remarkably successful songbird native to the western United States and Mexico that has been widely introduced across eastern North America. Key facts about its range include:
- Native range spans western North America
- Introduced and established across eastern United States and Hawaii
- Inhabits varied open and human-modified habitats
- Underwent rapid 20th century range expansion
- Remains one of the most numerous and widespread bird species in North America
The house finch owes its expansive geographic distribution to its adaptability, high reproductive potential, and tolerance of human landscapes. Despite some disease-related declines, it remains secure and continues to thrive across a diverse range stretching from Mexico to Canada.