Winter rations, summer forage

Coming to you through the miracle of voice recognition software, I thought I’d reflect this week on changes I’ve made in my policy toward feeding birds. For several years I filled two bird feeders every week. Then I read Gardening for the Birds, by George Adams.

    Adams recommends growing plants that feed birds and provide them with shelter. 

Cedar waxwing eating fruit of a native serviceberry

He’s not a fan of bird feeders in the warm months. He points out that bird feeders can attract aggressive birds and invasive bird species like European sparrows that hog all the food and drive away shyer birds. Rodents attracted by birdseed may eat eggs and baby birds.

    To tell the truth, I was beginning to feel that birds were eating us out of house and home. Flocks of European sparrows showed up every time I filled the feeders and snapped up all the food within a few hours. While I regard individual sparrows as having a legitimate right to live, even if their ancestors are not from North America, I was attracting too many of them and not feeding other species I’d like to welcome to my yard.

One sparrow is endearing. Twenty take over a bird feeder.

    Following Adams’ advice, I started to emphasize trees, shrubs, and perennials whose fruit and seeds would provide food for birds. I already had some of them: balsam fir (Abies balsemea), shadblow (Amelanchier arborea), trumpet honeysuckle (Lonicera sempervirens), and lowbush blueberry (Vaccinium corymbosum). I added American elder (Sambucus canadensis) and American cranberry (Viburnum trilobum) for more bird-friendly fruit.

Mockingbird finds winter berries

    While I was choosing native perennials to attract native insects, I threw in some Eastern purple coneflowers (Echinacea purpurea), sunflowers (Helianthus species), and milkweeds (Ascelepias species), whose seeds birds could eat.

Purple coneflower seeds feed goldfinches

    One of Adams’ warnings was that birds might become dependent on food from feeders. If I suddenly stopped putting out seed, perhaps they would starve. I was interested to read an article in this month’s Atlantic that cites a Wisconsin study showing this didn’t happen in a population of black-capped chickadees. 

Black-capped chickadee--photo Alain Wolf

Researchers compared mortality among birds accustomed to getting some of their food from feeders and birds that foraged completely on their own. When feeder food stopped being available, the birds that had been fed did just as well as they had before. They were only taking 21 percent of their food from the feeders, continuing to forage widely despite this food source.  Bird feeders did help the chickadees get through the worst winter weather.

Bird feeders help birds survive the coldest days

    Scientists have also found that birdseed provided by humans is influencing birds’ evolution. Species are developing heavier beaks for opening sunflower seeds they find at feeders but not in their natural habitat.

    This year I’m putting out birdseed only in winter. I was happy to see that the native birds soon reappeared at the feeders this December, but the European sparrows aren’t back. I can’t judge yet whether more birds or bird species have been attracted by my plantings. All I can say is, there are lots of birds flitting around in spring and summer. I hope I’m heading in the right direction.

A sight I'd like to see

Mouths to feed

On a cold, snowy winter’s day, it’s lovely to see wild birds in the backyard. Last week I spotted nuthatches and a woodpecker at the suet feeder, chickadees hopping around the big hydrangea vine, and a female cardinal scoping out territory for this spring’s nest. Although my garden doesn’t attract rare, shy birds (or if it does, I don’t know enough to spot them), I like the idea of providing food and habitat on my suburban lot.

Thistle seed attracts small birds, including goldfinches

So it was a jolt to read in Cornell Lab of Ornithology’s magazine that “. . . although feeding birds may not be harmful to the species that use feeders the most, it also isn’t helpful to the species that most need our help.” Emma Grieg, leader of the lab’s Project FeederWatch, goes on rather condescendingly, “But don’t take down your feeders in despair. One of the most important impacts of feeding birds is that it allows people to feel connected to the natural world.”

    Wait a minute—harmful? Research by Grieg and Cornell Lab Citizen Science Director David Bonter assesses the balance between positive impacts of bird feeders—supporting populations of regular feeder guests such as northern cardinals—and negatives, such as “disease transmission, deaths from window strikes (when birds fly away from a feeder and into a house), and increased predation pressures," as when hawks eat bird feeder birds.

It's squirrel-proof, but is this feeder bad for backyard birds?

    I’m one of more than 50 million North Americans who feed backyard birds. I have a tube feeder for mixed seed, a hopper feeder for sunflower seeds, a thistle feeder, and the suet feeder for woodpeckers and nuthatches that like to eat hanging upside down. Last fall I bought ten 20-pound bags of birdseed at Mass Audubon Broadmoor Sanctuary’s Bird Seed Day Fundraiser. 

Blue jays are fun to have around

     I’d never thought there could be anything negative about bird feeders until I read George Adams’ book Gardening for the Birds: How to Create a Bird-Friendly Backyard.

     In addition to the potential harm noted by the Cornell researchers, Adams points out that birds evolved to forage for seeds and insects on their own. If they come to depend on food from our feeders, they could go hungry when we leave town. Also, we may be changing population dynamics, causing booms in feeder-reliant species, including nonnatives such as European sparrows.

Flocks of European sparrows can grab all the available food--Hopkinton News photo

     Is feeding birds just a feel-good activity, another ham-handed human intervention that gets in the way of natural processes instead of helping?  The Cornell article presumes that our goal in feeding birds is to save endangered species. 

     That’s one goal, but I have others. In winter, I’m proud to feed ten native species on Mass Audubon’s list of common backyard birds of the Northeast. I think they deserve to flourish, even if they’re not rare, and I know they’re contributing to the health of my garden ecosystem. 

Downy woodpecker hunting for insects

       To encourage birds to do their part in the garden by eating insects, I’ve stopped putting out seed in summer. I just need to get in the habit of washing those feeders more often.

Feeders need cleaning so they won't transmit diseases between birds