Cover photo: © Michael Janke, 2016, some rights reserved.
From its pet shop introduction to the east coast to its ties to the study of disease spread, the cheerful house finch has a great story under its bright exterior.
Places to See House Finches
Male house finches are reddish in color, while females are brown.
House finches are small songbirds – typically 5 to 6 inches in length. The males and females are sexually dichromatic, meaning that they differ in color. Male house finches have red heads, breasts, and rumps (the region just above the beginning of the tail). Males can have some variation in coloration, depending on their diet. Their wings and the rest of their body is brown. Females birds are brown and streaked.
House finches, like many other finches, have notches at the ends of their tails. They have small, cone-shaped bills and thin legs.
Above: Male and Female House Finch – © JanetandPhil, 2015, Flickr Photo Album, some rights reserved.
House finches are native to the western U.S., but have expanded out east.
House finches are native to the western part of the United States. In the 1940’s, a group of house finches were introduced to the eastern part of the United States. Since then, they have become a common sight all across North America. In some parts out east, populations of house finches will migrate short distances during the winter.
House finches can often be found in urban areas alongside humans.
While their native habitat was probably patchy areas near streams and grasslands, house finches have adapted well to living alongside humans in urban areas. House finches are commonly seem in vegetated neighborhoods and are frequent visitors to backyard bird feeders.
Male house finch coloration is the result of their diet.
House finches will eat seeds, buds, berries, and some small insects, such as aphids. At my home bird feeder, black oil sunflower seed is a favorite among visiting house finches.
Did you know male house finch diet is directly correlated with their coloration? Carotenoid pigment deposits in feathers are responsible for the males’ coloration. Differences in the concentrations and types of pigments for different males are what result in the variation of color.
House finches have a beautiful, flowing song.
House finches have a sweet, flowing song that’s commonly heard from treetops in neighborhoods. For examples of what they sound like, check out this page from the Cornell Lab of Ornithology.
House finches build cup nests and raise their young together.
Male and female house finches form pairs which sometimes last the entire year. To woo females, males will perform displays in which they sing and flutter upwards, then glide back down.
House finches nest above the ground, using locations that vary from vegetation to man-made structures. The females will do most of the building, constructing a cup nest made of fine twigs and grass. The clutch size, or number of eggs laid in a single nest, averages 4 – 5 eggs. Their eggs are pale blue in color.
After approximately 2 weeks of the female’s incubation, the eggs will hatch. The male and female take turns feeding the young until they leave the nest after about 2 weeks.
A pet shop heist resulted in the introduction of the house finch to the east coast.
In the 1940’s, pet shop owners were illegally breeding and housing house finches in New York City. To avoid prosecution, the shop owners released their birds. Thus began the introduction of the house finch to the eastern part of the United States. Since, house finches have established themselves all across the east. In some areas, populations of house finches have evolved to undergo short migrations south during the winter.
House finch studies give us insights on the spread of disease and the virulence of viruses.
In 1994, reports began showing up of a new sight at backyard bird feeders. The charismatic house finch, a beloved songbird, began showing up at some feeders with swollen, red eyes. Upon closer inspection, it was found that the ailment was caused by a poultry virus (Mycoplasma gallisepticum) that made a species-jump over to house finches.
This epidemic had a silver lining – the newly-arrived pathogen offered a natural study system by which to research disease spread. Headed by André Dhondt of the Cornell Lab of Ornithology, a citizen science-based program was created to monitor the spread of the house finch disease. The team was able to successfully track the spread of the house finch disease from the east coast all the way across the United States using mailed surveys. These data, along with other existing data on the abundance of birds before the introduction of the disease, made this study on wildlife disease novel.
The work didn’t stop there, either. After successfully monitoring the disease spread, the team turned to bigger questions about disease spread and pathogen virulence, or the severity of pathogen harmfulness. The work that began with mailed surveys led to groundbreaking research on diseases – work that is applicable to the human disease outbreaks that dominate headlines today.
For more detailed information on house finch conjunctivitis and the history of these studies, check out this article.
Resources to learn more: