Nature Nut: House finches took an unlikely path to get here

February 3, 2019

It seems like I have written a lot about birds lately, perhaps because even in our coldest weather many are still around and visible.

On one of the recent sub-zero days, a group of birds in my backyard caught my attention. More than 15 of them, they could be seen gathering in a 5-foot high shrub 30 feet from my feeder.

At any given time, there were up to eight of them at the feeder, after which they would return to the shrub and others would take their turn. I couldn’t help but wonder what kind of system they had that did not lead to total feeding chaos. I also wondered if most humans would behave together so well under stress of an “eat or die” situation.

I assumed these birds were house finches, one of the dominant species at my feeder this winter. But getting closer looks with camera and binocs stymied me for a while. The red of the males seemed more brilliant, and bodies looked totally different, as their feathers were fluffed out to trap air, providing added insulation against the brutal cold.

I had discounted purple finches, as they are almost identical to house finches, except males are a bit more purplish than red, and females have white eye line. My only other thought was redpoll, a northern bird having quite a bit of red coloration like male house finches, but rarely seen around here. But, with a quick look at online pics of redpolls, I discounted them and realized these were indeed house finches.

Such a view is something I wouldn’t have had as recently as 30 years ago, as house finches are not native to Minnesota or any other state east of here. I find the story of their spread throughout the eastern United States quite amazing. Based upon numerous reliable sources, house finches, which historically ranged throughout western states, became common in eastern states because of pet shop owners in New York City.

In the early 1940s, these pet shops had obtained house finches from western states, selling them as “Hollywood Finches,” in part because of their melodious calls. But soon the Feds caught up with them, and with threats of being prosecuted under the Migratory Bird Treaty Act of 1918, owners turned the birds loose.

Amazingly, in less than 40 years, from a few dozen released birds they became one of the dominant birds throughout the country. In doing so, they often outcompeted the native purple finches, as well as another invader, the non-native house sparrows. However, on the bright side, I would say they are a step up from house sparrows, in that they are more colorful and better singers.

I recall years ago reading of the first house finch nest in Winona County, found in 1989. Shortly after that, I remember a house finch pair nesting in a hanging flower basket on my parent’s Northeast Rochester front porch, something I am sure many area residents have experienced since.

One of the factors that allowed house finches to so successfully colonize such a vast area in a short time is their ability to have two or three nestings, with large numbers of young each year. They also adapt well to living around people, in cities as well as agricultural areas.

House finch numbers seemed to peak in the early ’90s just before a disease spread through much of the population. It was caused by an unusual bacterial jump from chickens and turkeys to house finches. This conjunctivitis-like disease was first noted by people with feeders who saw house finches showing up with obvious eye problems, often shut, swollen, and crusty.

Alerted by this unusual occurrence, researchers began collecting data from thousands of birdfeeding “citizen scientists.” Their efforts were driven in part because of a fear this disease, which may have decimated half the house finch population, might spread to other native birds, possibly all the way to the tropics for many migrants.

Fortunately, that has apparently not happened, and while the disease is still present in house finches, it seems to have stabilized. I can’t help but wonder if the birds were susceptible to this disease in part because the eastern population originated from such a small gene pool with the pet shop releases.

Regardless of how house finches got here, they are probably here to stay, at least as long or longer than we are. So, enjoy their color and sounds, and put up a hanging basket if you want to watch their life cycle unfold.

Update hourly