By Mary Jo DiLonardo │TreeHugger│5 min

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It can be a bit of a backyard quandary for bird lovers. If you feed the birds, will that make them so dependent on human help that they won’t forage elsewhere?

A new study finds that although songbirds will regularly visit the feeders, they’re unlikely to develop an unhealthy reliance on them, even when they might need them more.

Study author Jim Rivers, an assistant professor of wildlife ecology in Oregon State University’s College of Forestry, has been interested in birds since he filled the feeders in his backyard growing up.

“As a kid, I remember the adage of always making sure your feeders are filled and, particularly, make sure you do that before birds might be going through some energetically challenging weather conditions like a big storm coming through or particularly cold weather,” Rivers tells Treehugger.

Now, as a researcher, he started looking into it. There was one earlier study from 1992 where researchers just took feeders away and monitored the survival of the birds. They found that birds weren’t dependent on human help.

This time around, Rivers wanted to look at more challenging circumstances.

For the study, Rivers and his colleagues chose to use the black-capped chickadee, a small bird that is found throughout North America. The birds will often take just one seed from the feeder at each visit, which makes it easy to measure how often they visit.

Researchers caught 67 birds and either left them alone as a control group or clipped some of their feathers. Clipping is a way to increase the energy birds spend while flying. In some of the birds they did a light clipping, removing just a few feathers; in others, they performed a heavier clipping.

They also tagged each bird with an RFID tracking chip before releasing them. The chips are unique to each bird.

The researchers placed 21 feeders around their study area with perches that work as antennas. Each time the birds land, they’re scanned in and the visits are recorded.

“We thought that the birds, because of their increased energetic need, would come to these feeders and spend a lot more time there,” Rivers says.

But that’s not what they found. Instead, the handicapped birds took a bit of a break (several days to a few weeks) before returning to the feeders. Then they used the feeders at a similar level as the control birds.

“So it was a surprise to us because we thought the birds would have the reaction of, it’s free food and they know where it is, so we thought that they would come back and use them at greater levels afterward but instead we saw essentially no real strong response,” Rivers says.

Because the trackers didn’t cover the birds except when they were at the feeders, the researchers aren’t exactly sure where they were when they were taking their break immediately after their wings were clipped.

They think the birds avoided feeders while they got used to their feather changes and a new way of flying. They were likely relying more on natural foods and possibly seeds they had stashed away. And then once they felt more comfortable, they went back to the feeders.

The results were published in the Journal of Avian Biology.

Bird Feeding Pros and Cons

Black-capped chickadee with an RFID chip band visits a chip-reader feeder.

Jim Rivers

Around 59 million Americans feed birds, according to the U.S. Fish and Wildlife Service. There are real benefits to filling the feeder for the birds.

They get easy-to-find reliable food, particularly in winter when it can be difficult to find a meal. Studies have found that winter survival is longer for birds in areas where they are fed regularly and more offspring might be produced in the subsequent breeding season.

There’s also a real benefit to people.

“We as humans have a much better appreciation of wildlife when we get to see them up close, we get to feel like we know them,” Rivers says.

“I’ve got a couple of young kids and we have a couple feeders in my backyard and it’s a great opportunity for them to appreciate the diversity of species that we have because we have finches and we have chickadees and hatches. And so I think that for a lot of people that’s their connection to nature. There are places where you can still feed birds, although you don’t have a lot of natural habitat.”

But there are drawbacks, too.

Diseases and parasites can be transmitted more easily when birds congregate at feeders. A recent mysterious illness, for example, has been blinding and killing birds in several states. Wildlife officials have asked residents to take down feeders until they know the cause of the outbreak.

Feeders can also make it easier for predators like hawks and cats to find an easy meal.

So feeding isn’t inherently good or bad.

“I think what our study allows us to say is that concern that I had as a kid that if I don’t get my seeds out before this big storm that birds can be in trouble. I think we can say that that’s not what’s going on at least based on our species in our study area here,” Rivers says. “We’re not going to be harming the birds and the birds aren’t going to starve or have big issues just because we didn’t fill up our feeders.”

“Before we were here these birds would have had evolved with these different settings, and they get through winter periods, they get through storms on their own so you know maybe we’re providing supplemental food but it’s not the point where we are changing their ranges or their behaviors,” Rivers says.

One caveat, he says is that researchers believe there are some species that may have changed their ranges due to feeders.

“Anna’s hummingbird is one that we have here in Oregon in the wintertime, and probably isn’t a bird that would typically winter here and it’s probably relying on winter feeding, as well as some of the plants that we put outside whether they’re natural or not.”

But by and large, most of the birds that people feed are those that already always had natural food sources, Rivers says.

“I don’t think people should be afraid to or worried about feeders, particularly for the feeder dependency issue but they also want to follow the kind of the best practices so that when we are feeding we’re not promoting disease or the negative impacts of feeding.”View Article Sources 

1. https://onlinelibrary.wiley.com/doi/epdf/10.1111/jav.02782
2. https://sora.unm.edu/sites/default/files/journals/jfo/v063n02/p0190-p0194.pdf
3. Study author Jim Rivers, an assistant professor of wildlife ecology in Oregon State University’s College of Forestry