The House Finch (Haemorhous mexicanus) is a common and adaptable bird found across North America, thriving in a variety of human-altered landscapes as well as natural environments. Understanding their habitat, diet, nesting habits, behavior, and conservation status provides valuable insight into this familiar species.
Habitat
House Finches are highly adaptable and commonly found in human-created habitats. They frequent areas with buildings, lawns, small conifers, and urban centers. In rural settings, they are often observed around barns and stables. Within their native western range, House Finches also inhabit natural environments such as dry deserts, desert grasslands, chaparral, oak savannas, streamsides, and open coniferous forests below 6,000 feet in elevation. Their ability to thrive in diverse environments, including those shaped by human activity, contributes to their widespread distribution.
Diet
The diet of House Finches consists almost exclusively of plant materials, with seeds, buds, and fruits forming the bulk of their intake. They consume a wide array of wild foods, including seeds from wild mustard, knotweed, and thistle, as well as mulberries, poison oak, and various cactus species. In agricultural areas and orchards, House Finches are known to feed on cherries, apricots, peaches, pears, plums, strawberries, blackberries, and figs. At bird feeders, they show a preference for black oil sunflower seeds over larger striped sunflower seeds, and also consume millet and milo.
Nesting
Nest Placement
House Finches exhibit flexibility in their nesting choices, utilizing a variety of locations. They build nests in both deciduous and coniferous trees, as well as on cactus and rock ledges. Additionally, they readily nest in or on buildings, selecting sites such as vents, ledges, street lamps, ivy, and hanging planters. Occasionally, House Finches may repurpose the abandoned nests of other bird species.
Nest Description
A typical House Finch nest is a cup constructed from fine stems, leaves, rootlets, thin twigs, string, wool, and feathers. The lining of the nest is made from similar, but finer materials. The overall width of the nest measures between 3 to 7 inches, with the interior cup being 1 to 3 inches across and up to 2 inches deep.
Nesting Facts
- Clutch Size: 2-6 eggs
- Number of Broods: 1-6 broods per year
- Egg Length: 0.6-0.8 inches (1.6-2.1 cm)
- Egg Width: 0.5-0.6 inches (1.3-1.5 cm)
- Incubation Period: 13-14 days
- Nestling Period: 12-19 days
- Egg Description: Pale blue to white, speckled with fine black and pale purple markings.
- Condition at Hatching: Hatchlings are naked except for sparse white down along feather tracts, with their eyes closed and limbs appearing clumsy.
Behavior
House Finches are highly social birds, rarely observed alone outside the breeding season. They often form large flocks, sometimes numbering several hundred individuals. Their foraging behavior primarily occurs on the ground, at bird feeders, or in fruiting trees. When at rest, they commonly perch on the highest available point in a tree, and flocks frequently congregate on power lines. During courtship rituals, males may engage in food-sharing displays with females. This behavior begins with the female gently pecking at the male’s bill and fluttering her wings. The male then simulates regurgitating food to the female multiple times before actually feeding her.
Conservation
House Finches are widespread throughout the U.S., parts of Canada, and Mexico. While their populations showed a slight decrease between 1966 and 2019 according to the North American Breeding Bird Survey, they are generally considered a species of low conservation concern. Partners in Flight estimates a global breeding population of 40 million and rates them 6 out of 20 on the Continental Concern Scale. These birds often benefit from human development and habitat modification.
However, certain populations have experienced a significant decline since January 1994, primarily due to a disease known as mycoplasmal conjunctivitis. This illness causes respiratory problems and red, swollen eyes, leaving affected birds vulnerable to predators and harsh weather conditions. House Finch conjunctivitis was first identified at feeders in the Washington, D.C. area and has since spread rapidly through both eastern and western House Finch populations. Continued monitoring and research are important for understanding and addressing any future conservation challenges for this adaptable species.
Credits
- Badyaev, Alexander V., Virginia Belloni and Geoffrey E. Hill. (2012). House Finch (Haemorhous mexicanus), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
- Dunne, P. (2006). Pete Dunne’s essential field guide companion. Houghton Mifflin Harcourt, New York, USA.
- Ehrlich, P. R., D. S. Dobkin, and D. Wheye (1988). The Birder’s Handbook. A Field Guide to the Natural History of North American Birds, Including All Species That Regularly Breed North of Mexico. Simon and Schuster Inc., New York, NY, USA.
- Lutmerding, J. A. and A. Love. (2020). Longevity records of North American birds. Version 2020. Patuxent Wildlife Research Center, Bird Banding Laboratory 2020.
- Partners in Flight (2019). Avian Conservation Assessment Database, version 2019.
- Sauer, J. R., D. K. Niven, J. E. Hines, D. J. Ziolkowski Jr., K. L. Pardieck, J. E. Fallon, and W. A. Link (2019). The North American Breeding Bird Survey, Results and Analysis 1966–2019. Version 2.07.2019. USGS Patuxent Wildlife Research Center, Laurel, MD, USA.
- Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.
