I regularly get asked questions about bird feeders: the best designs, most nutritious foods, styles different birds like, how to keep feeders clean, repairing damaged feeders, and more. One of the more interesting questions, however, is how essential are feeders, really? How much food do birds get from our feeding stations?

Birds’ Natural Food Sources

It’s no secret or surprise that habitat loss affects birds. When habitat is destroyed through development, cultivation, poor management, natural disasters, or artificial crises, birds lose not just space, but everything within that space. Trees, shrubs, and grasses that provide shelter and nesting spaces for birds are no longer available, and the seeds, nuts, fruits, and nectar provided from different plants are also lost. So are prey animals, including insects, small mammals, fish, worms, and other food birds might rely on. As these food sources dwindle, birds will use their natural curiosity and inquisitiveness to seek out more unusual food options, and they will readily begin visiting feeding stations.

Birds at Our Feeders

No matter what habitat loss may be going on nearby, backyard birders can replace some of those natural food sources in their own yards. Native plants and bird-friendly landscaping can provide foraging spaces and natural foods, as well as the shelter essential for birds to stay safe.

Even more easily, feeding stations provide direct supplemental feeding with seeds, nuts, jelly, suet, nectar, and other treats. Even just one feeder can make a difference to local birds, and birders who offer a range of different foods from different feeders will quickly see a diverse flock of birds arriving in their yard for regular meals.

How Much Are They Eating?

When so many birds visit a feeding station – even a large feeder might be empty in just a day or two when a hungry flock finds it – it can seem as if birds are getting all their nutrition from supplemental feeders. That impression is incorrect, however, and even the most common yard visitors, such as northern cardinals, American goldfinches, and blue jays, only get a small amount of their daily food from feeders.

While the exact numbers vary depending on the bird species, the richness of surrounding habitat, climate conditions, and the time of year, birds generally only get 10-25 percent of their food from supplemental feeders. In urban areas where natural spaces are scarce, the percentage may be a bit higher, and it will also be higher in winter when natural foods are not being replenished. In wild areas and more bountiful seasons, however, birds may get much less food from feeders.

These numbers may seem startling to birders, particularly when feeders are emptied quickly and you can easily watch dozens of birds happily feeding each and every day. Doesn’t that prove that birds are getting a lot of their food from feeders?

The Vending Machine

Imagine your bird feeder as a vending machine in a busy high school hallway. All you can see is the vending machine, and each day you see plenty of snacks disappear as hungry teens devour candy, granola bars, chips, cookies, and other snacks. It could be easy to believe that those teenagers would be miserably hungry, even starving, if that machine was empty or removed. But consider what you aren’t seeing, if all you watch is one vending machine. You wouldn’t notice…

• Lines in the cafeteria as students get hot lunches
• Cooler bags in lockers for students who brought food from home
• Other vending machines in different parts of the school
• Meals students eat before and after the school day
• Snacks bought from the convenience store around the corner
• An apple plucked from a tree on the walk home
• Refreshments provided at school activities
• Treats tucked into backpacks or coat pockets

For birds, our feeders are vending machines. They’re easy to use and offer convenient treats but they’re far from the sole resource for an overall daily diet. Like teenagers, birds forage throughout the day, in different places, and for different foods to make up their complete diet.

When Feeders Are Empty

Still, it can be distressing to think of birds missing snacks or meals if feeders are empty. What will happen, however, is just like a hungry teenager heading for the next vending machine, opening the fridge, browsing the cupboards, or raiding the pantry, a hungry bird will simply move on to another food source if a feeder is empty. They know where the most abundant foods are, they know where less-than-favorite but still good treats can be found, and they know where emergency options exist. Just as some teens will even stash an extra candy bar in their desk or hide a bag of chips under their bed, some birds even cache food so they can revisit their storage if other food sources aren’t available.

Why You Should – Or Shouldn’t – Keep Feeders Full

Of course, no parent wants their child to go hungry, and no backyard birder wants birds to miss a meal. Leaving a feeder empty for a few days can be helpful, however, because…

• It encourages birds to return to other food sources rather than rely on just one feeding location, giving them more opportunities to browse for other foods and more diverse nutrition.
• Birds are more apt to clean up under an empty feeding station, ensuring that no seeds are wasted and making the most of every dollar spent on birdseed.
• As birds disperse to other feeding spots, they are less likely to spread contagious diseases among the backyard flock, which will help keep the entire local bird population healthier.

In some cases, however, it is best to not let feeders remain empty for long. When birds are heavily stressed, a reliable, easy food source – that convenient backyard feeder – can make a great difference in birds’ survival. Parent birds, for example, must forage much more frequently and effectively to feed a hungry brood, and a good feeder can be a great resource during the nesting season. Similarly, harsh storms and poor weather – from hurricanes and floods to blizzards and deep freezes – can make it difficult for birds to forage safely, and a good feeder can help them survive until more favorable conditions prevail. At these times, it is great to keep feeders full of the best, most nutritious foods.

Don’t, however, ever feel guilty if your feeders may be empty for a day or two, or even longer. Maybe your schedule is too busy to get to one more chore, or you’re traveling and out of town, or you’re just sick and laid up yourself. Maybe the bird feeding budget needs to stretch a bit further, or you want birds to disperse a bit because of diseases or other backyard risks. When you are able to refill the feeders, the birds will be back, enjoying every bite even as you enjoy their visits.