Last Updated on December 17, 2021 by Nancie

Filling Feeders: Should you keep your bird feeder full at all times? Or should you only add seed when it is completely empty? I’ve been experimenting a bit with this and my conclusion is that how full you should keep your feeder depends on feeder type and sometimes weather. You can also somewhat control the feeder area’s bird density by adjusting seed availability among several feeders.
Estimated reading time: 9 minutes

Filling Tube Feeders With All Bottom Ports
When I Let Bottom Port Tube Feeders Go Empty
Some tube feeders have a long column to fill with seed, but all the ports are near the bottom. Squirrel Buster Plus feeders are an example of this feeder type. My usual approach is to fill this type feeder up and then not add more seed until it is empty. This encourages good seed turnover. Depending on your specific tube feeder’s design, it can make it less likely that seed lingers in the feeder to go bad. It is also easier to shake excess bits from an almost empty feeder so you can start fresh.
When I Keep Bottom Port Tube Feeders Full
But there are times when I do top off these feeders instead of letting them go empty first. One obvious example is when I am planning to go away for a few days. I’ll top off all my feeders so the seed is more likely to last until I get back. I might also top off my tube feeders before/during a snow storm when there are more birds than usual eating. Pre-filling them before a storm can also save me having to go out and refill them in bad weather.
Another weather-related time that I keep hanging tube feeders topped off is when weather forecasts call for strong wind. I’ve found that tube feeders are usually pretty stable in light wind. But feeders can blow around if you have baffles or weather domes over them that can catch the wind. Filling feeders to the top can add enough weight to keep them from kiting around unless the wind is super strong or the food is unusually light-weight.

Filling Tube Feeders With Ports Scattered Along the Tube
Other tube feeders have a series of ports along half or more of the length of the tube column. These are often arranged in groups of two opposite facing ports. With this type of feeder, if you let the seed level go down, the upper ports won’t provide access to seed but lower ports still have seed. One example in my yard is the Squirrel Buster Classic feeder with two sets of port pairs on the lower half of the tube. Other examples are the Woodlink caged tube feeders and Aspects nyjer feeders. These have ports in several paired groups along the tube’s length.
When I Keep Many-Port Tube Feeders Full
My approach for these feeders varies. If we are expecting bad weather where a lot of birds will be visiting or if it is supposed to get windy, I top the feeders off so they start out full. During snow storms, I’ll probably continue topping them off to give more birds a chance to eat.
I don’t find I usually have to keep topping off feeders during very windy days because I notice birds are often less likely to come to the feeders in high winds. (Note: If winds are expected to be extremely strong, I’ll take both the feeders and their baffles down.)

When I Let Many-Port Tube Feeders Go Half Empty or Empty
But when the weather is warm and/or calm, especially in summer and early fall months, I don’t constantly top off these feeders. On warmer days, there aren’t typically as many birds visiting. I also have enough feeders that if some feeder ports don’t have seed, there are still others with seed.
As with other tube feeders, it can be good to at least occasionally allow a feeder to go completely empty. That way you know that all the seed gets eaten. By adding new seed at that point, it is all fresh. (If you have several feeders, you might let one gradually go empty while another is still filled so there is still seed available.)
Also, keeping a lot of feeders full can at all times encourage large flocks of one bird species. While it can be fun to brag about dozens of goldfinches visiting daily, there are downsides even when it is a bird species you like. For example, there are times when I have so many finches (usually House Finches and American Goldfinches) that I worry a bit about bringing so many birds into one limited area to eat.
By spreading these popular feeders out around my yard and not always completely filling all of them, it spreads the flock out. I think reducing bird density at feeders makes sense as a way to try and reduce spread of disease like House Finch conjunctivitis and avian pox.
These particular bird species still flock together and roost together. That’s their nature. But at least they are spread out a little more at my feeders. When every last feeder port isn’t full of finches, it also seems to encourage other species to visit. Spreading out the finches has encouraged more visits from small birds like chickadees, wrens, nuthatches and titmouses.

Still Checking Tube Feeders Daily
One thing you have to watch with some of these feeders though is the seed distribution in a half-full feeder. When full, the seed’s total weight and volume encourages the seed to settle down inside the tube so that there is seed at all the ports. But if you let the feeder go half empty, you might find air pockets inside the tube. Then, sometimes the bottom ports will go empty even when there is still seed higher up in the tube. This is probably more likely with some seed (like sunflower hearts) than others.
It can be hard to pick up on this problem when viewing a feeder from a distance. So even if I don’t top off these feeders every day, I check the ports and give the feeders a quick up and down shake to redistribute the seed down the length of the feeder as needed.
Then when the feeder is empty, clean it if necessary and refill it. When topping off or refilling a feeder, check to make sure there isn’t seed that has gone bad stuck in it somewhere. Usually this happens around the ports where rain can get in or near the bottom where seed can get stuck in some feeders. If you see bad seed lingering there, clean out the feeder before refilling.

Keeping Platform Feeders Full?
I’ve always been a host who doesn’t want to run out of food or drink if I’ve invited people over. So I tend to make or buy too much just to be sure. With people, that just means leftovers and not having to cook the next day, so no worries. But I have tended to do the same thing with my platform feeders. This is fine when there is a snowstorm and it all gets eaten in a day. But it can be a problem at other times when food sits in a feeder too long, gets wet and goes bad. (Platform feeders I use are the BirdsChoice Fly-Through Platform feeders and BirdsChoice Hanging Platform feeders.)
Downsides of a Too-Full Platform Feeder
So I’ve been intentionally restricting my filling of platform feeders so that they go almost completely empty between refills. Previously, I would regularly top off platform feeders even if there was still seed left in them. By indiscriminately adding seed every day, the seed level would gradually get deeper. This encouraged birds to eat the fresh seed on top while seed lingered underneath and in corners. The longer seed sits in an open platform feeder, the more it will get pooped on (encouraging disease spread) and the more likely it will get wet and moldy.

Advantages to Letting A Platform Feeder Go Empty or Almost Empty
To always have some seed available, it isn’t necessary for feeders to always be full. So now I check the platform feeders each day and only add seed if the feeder is empty or almost empty. This has dramatically reduced wasted seed at these feeders. Just this small change means that the seed in these feeders is cleaner and fresher. Over time you get a feel for how much seed is eaten each day at different times of year. So there is still plenty of seed for the birds to eat.
Another advantage to not filling platform feeders too deeply is that some birds sweep their beaks through seed to find what they like. Often this seed winds up as a mess on the ground underneath. European Starlings are the worst offenders in my yard. But if the platform feeder’s sides are a few inches high and the seed depth isn’t going up to the top, less of that seed winds up on the ground where it may or may not get eaten.

Do You Keep Your Feeders Full?
That’s how I’m filling my feeders these days. How often do you fill your feeders? Do you let them go empty or does keeping feeders topped off and full work better for you? As always, your thoughts and comments are welcome below.
Nancie
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I totally agreed with your comments on refilling feeders. I used to try to keep all my feeders, of various styles, full all the time, but now I have reduced the number of feeders I put out as well as what kind of seed I use and how often I refill my feeders. This is because I don’t seem to be getting the numbers and species of birds that I used to see and I am trying to reduce the amount of waste produced by the feeders. Except for safflower seed, I use only shell-less sunflower seed (whole and chips) and peanuts in tube and mesh feeders. On my one platform feeder, I put out about a cup or so of a mixture of these seeds late in the afternoon each day. I find that at this time of day, house sparrows and starlings/grackles are less likely to hog the platform and this gives more “desirable” species a chance to feed. If anything is leftover, the early morning birds will finish it off. I also keep a couple of suet cakes out, one in an upside-down suet feeder for woodpeckers and nuthatches, and one on my platform feeder for wrens, titmice, chickadees and anything else that wants to work at the suet. Doing all this seems to be working, in that the food is completely eaten quickly, makes less mess around the feeders, and attracts the kind of birds I most enjoy seeing at my feeders. I don’t worry about letting feeders go empty, as “my birds” always come back when they see that the feeders have been refilled.
Hi Diana,
Like you, I think it can make a lot of sense to pause and reevaluate this kind of thing. It can be so easy to get into a rut and just do what you’ve always done. But I’ve found that things do change among the birds that visit feeders and sometimes we can make changes that make things better for both the birds that visit and for us. It sounds like you’ve found a way that is working really well for you which is very cool.
I agree too that birds pay attention and will circle back around to feeders as long as they are refilled regularly. Often my feeders will be quiet. Then I’ll go out and refill them and step out of the way. Within minutes birds start appearing to check out what I’ve added. They definitely pay attention. LOL
Thanks for sharing,
Nancie
A detailed guidance. Thanks for your sharing. I think it is best that we refill feeders right away, but not just to feed the birds. I’ve always done that and realized some benefits like this. Reliably full feeders keep birds visiting frequently because they recognize the feeder as a good food source. A feeder that is irregularly filled will not get as many loyal visitors. Besides, seed will stay fresh if it is eaten more quickly so it does not spoil. Birds typically avoid spoiled seed, which could be toxic if ingested.
Hi Birdnature,
I definitely agree that reliably offering food encourages birds to stay around and/or come back often. I suspect that whether to keep every feeder filled to the top at all times may depend in part by how many feeders you have. If you have quite a few feeders, as I do, if one goes empty, there are others that still have seed to spare.
I used to keep every one of my feeders topped off at all times but now I usually only refill a feeder when all the food in it is eaten or almost all. I’m finding that doing it this way doesn’t leave a layer of uneaten food as a bottom layer that can spoil. Instead, within a day or two, all the food is eaten while it is still fresh. Then I refill the feeder for the next day or two. The result is less waste, less spoiled food and hopefully healthier birds at my feeders.
That said, doing it this way means I have to keep an extra eye on the feeders so that I can refill them right away. My goal is to always have food available but not have so much that it goes bad before it can be eaten. It’s a balance.
Thanks for sharing!
Nancie
Mum usually lets her platform feeder go fairly empty before refilling. She’s home most of the time since she’s retired and with recent events, hasn’t been able to travel like ahe usually does in January/February to combat seasonal depression. To be fair, it doesn’t take long for the feeded to get empty. Last weekend I watched it go from filled to the brim to empty in just three days. So far she hasn’t had any issues with seed going bad. Mostly because it gets eaten so quickly and it has a fairly sheltered “roof.”