A flock of grackles can empty a feeder in an afternoon and keep every chickadee and finch in the neighborhood away while they do it. Red-winged blackbirds, cowbirds, and starlings do the same thing in smaller numbers. They aren’t villains, they’re just big, social, and fond of cheap seed, and that’s the whole solution: change the food, change the feeder, and they leave on their own. Here’s what works, in the order to try it, and what to skip.
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The short version
- Change the seed first: safflower or striped sunflower. Songbirds eat both; grackles and blackbirds mostly won’t bother.
- Best feeder fix: Squirrel Buster Plus, with the weight spring set to shut out grackle-sized birds.
- Cheapest feeder fix: a caged tube feeder that only small birds fit through.
- For suet: an upside-down suet feeder. Woodpeckers and chickadees feed hanging; grackles and starlings can’t.
- Stop doing: mixed seed, ground feeding, and platform feeders while the flock is around.
Not sure whether you have grackles, red-winged blackbirds, starlings or cowbirds? Our guide to telling grackles, blackbirds and starlings apart sorts them out in about ten seconds. And if you want to know why these birds go for the tray and the cheap mix but skip safflower, see what grackles eat, and if a flock showed up overnight, why grackles flock in fall and how long they stay.
Know which bird you have
Common grackle: larger than a robin, glossy black with a purple-blue head that shines in sun, a long keel-shaped tail, and a pale yellow eye. Travels in flocks, walks rather than hops, and is the one that shows up forty at a time in spring and fall migration. Red-winged blackbird: smaller, the male jet black with red-and-yellow shoulder patches, the female streaky brown like a big sparrow. Comes to feeders mostly in late winter and spring. Brown-headed cowbird: stocky, the male glossy black with a chocolate head. European starling: not a blackbird at all, but the same behavior: short tail, yellow bill in spring, speckled in winter, and the one that will strip a suet cake by noon. Everything below works on all four.
Step 1: Switch the seed
This solves it more often than anything else. Blackbirds and grackles have soft, straight bills built for insects and grain. They love millet, cracked corn, milo, and the cheap mixes made of them, and they’ll happily eat black-oil sunflower because the shell is thin. They struggle with two seeds that the birds you want handle easily.
Safflower is a white seed with a bitter, hard shell. Cardinals, chickadees, titmice, house finches, nuthatches, and doves eat it without complaint; grackles, starlings, and most blackbirds try it once and leave. Squirrels dislike it too. Striped sunflower has a shell thick enough that only birds with strong cracking bills (cardinals, jays, grosbeaks, chickadees working at it) get in; grackles give up. Fill every feeder with one or the other for two weeks and the flock usually moves on. Expect a slower week from the songbirds while they adjust.
Step 2: Change the feeder
Grackles need something to stand on. Take that away and they can’t feed no matter what’s inside.
Weight-activated
The Squirrel Buster Plus is sold as a squirrel feeder, but its adjustable spring is the best grackle solution on the market. Set the tension so the shroud closes under anything heavier than a cardinal, and grackles, starlings, jays, and squirrels all lose access while everything smaller feeds normally. It solves two problems for one price.
Caged
A tube feeder inside a wire cage with 1.5-inch openings admits chickadees, finches, nuthatches, titmice, and small woodpeckers and shuts out everything grackle-sized. It also keeps cardinals out, which is the trade-off. The adjustable-grille caged feeder lets you widen the openings once the flock leaves.
Tube feeders without trays
Any tube feeder with short perches and no seed tray on the bottom is hard for a grackle to use. If yours has a tray, take it off. Cheap fix, partial result.
For suet: feed upside down
Starlings and grackles will hang on a standard suet cage and eat the cake in a morning. An upside-down suet feeder puts the cake under a roof so the only way to reach it is clinging from below, which woodpeckers, nuthatches, chickadees, and wrens do naturally and blackbirds can’t. Skip hot-pepper suet for this job: birds don’t react to capsaicin the way mammals do, so pepper keeps squirrels off the cake but won’t stop starlings. Our starling guide covers the feeders that do.
Pigeons crowding the feeder too? The same fixes work on them. Here’s the full answer to are pigeons dirty birds? and how to keep them off feeders.
Step 3: Stop the ground buffet
Grackles and blackbirds prefer to feed on the ground, and a feeder that spills seed is feeding them under it all day. Stop ground feeding entirely while the flock is around, rake up hulls under the feeders, put a seed tray under tube feeders to catch what falls (yes, that’s the tray you removed from the feeder itself; move it to the pole), and take down any platform or tray feeder for a few weeks. If you keep a platform for cardinals, fill it with safflower only.
Step 4: Wait them out
Most grackle and blackbird problems are seasonal. The big flocks are migrants moving through in March–April and again in September–November, and they stay two or three weeks in any one yard. In nesting season the same birds split into pairs and mostly eat insects. If you switch the seed and pull the trays when the flock arrives, you’re usually back to normal before you’d have finished installing anything more elaborate. Starlings are the exception; they stay all year, and the upside-down suet feeder and caged feeder are permanent fixtures where starlings are thick.
What doesn’t work
Mylar strips, shiny balloons, fake owls. Grackles are among the smartest birds at a feeder. They notice a fake owl for about a day. Ultrasonic repellers. No evidence, and birds barely hear the frequencies anyway. Shooting or poisoning. Grackles, red-winged blackbirds, and cowbirds are protected under the Migratory Bird Treaty Act; harming them is a federal offense. Starlings aren’t protected, but poison put out for them kills everything else too. Taking the feeders down for a day. A flock that found your yard comes back the next morning. Two weeks of safflower is what actually resets them.
Common questions
Will grackles hurt the smaller birds? They bully them off the feeder and occasionally kill nestlings, but at a feeder the harm is mostly lost seed and displaced songbirds. The songbirds come straight back once the flock moves on.
Do grackles eat suet? Yes, and starlings more so. The upside-down feeder is the fix.
Can I just feed the grackles somewhere else? You can, with cracked corn on the ground at the far side of the yard, and it takes pressure off the main feeder. It also makes the flock stay longer. Better for squirrels than for grackles.
Why are there suddenly hundreds of blackbirds in my yard? A migrating or winter-roosting flock found a food source. Pull the trays, switch to safflower, and stop ground feeding; they’ll be gone in days.
Bottom line
Safflower in every feeder, trays off, ground feeding stopped, for two weeks. If that’s not enough, or starlings are the problem, the Squirrel Buster Plus on its heaviest setting and an upside-down suet feeder end it for good. Same principles as keeping squirrels off feeders: take away the seed they want and the perch they need, and the problem solves itself.
Related: How to keep squirrels out of bird feeders · Winter backyard birds by region · The best window bird feeders
