12 Aggressive Birds you’ll Find In Your Backyard

Are you finding aggressive birds in your backyard a huge issue?

Well, you’re not alone.

This aggression can range from loud chirping and chasing birds to dive-bombing humans or killing other birds.


You’ll find that most backyard birds will show aggression at some point.

Wild birds are very territorial, particularly males during the breeding season.

But have you ever noticed that there seem to be common culprits for these behaviors?

And you’d be right.

Some bird species are much more aggressive than others. This can be a real problem particularly if you’re wanting to attract a certain species to your yard.

These aggressive birds can scare other rarer and more placid bird species away from your yard.

If you spot one of the species in this list at your yard feeders it may be game over for more desirable birds like chickadees, purple martins or hummingbirds.

Want a solution? Then check out my guide on how to get rid of bully birds at feeders in your yard.

But for now this guide we’re going to look at the most aggressive bird you’ll find in your backyard.

So let’s begin.

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Aggressive birds in backyard

12 Aggressive Birds In Your Backyard

1. Gray Catbird

Catbirds are particularly aggressive backyard birds.

In fact, their name gives away a little about their behavior.

Catbirds hide in shrubbery and make cat-like noises to warn off predators and other birds.

Why are Catbirds aggressive birds?

Catbirds are very territorial.


Well, they breed twice a year. That means the males not only have to compete for mates. But they find a good area to nest in, and then protect their nest until their babies grow.

Being aggressive is a way for their young to survive.

Gray catbirds are also known to destroy the eggs of other birds such as Sparrows and robins.

Scientists don’t know why they do this. But, the less competition there is for a catbird’s chicks, then the more likely they are to survive.

2. American Robin

American robins are a bird you’ll be familiar with in your backyard all year round.

The main way Robins show aggression is by puffing up their red breast and signing loudly.

A Robin’s most common aggressive behaviors are posturing and signing to protect their territory.

Why are Robins aggressive birds?

The most aggressive time for Robins is males’ during the spring breeding season. Again this is to protect their territory and young.

Males can also be mainly aggressive when they are trying to take over territory from another bird.

Robins will drive away intruders fiercely. This can be other bird species or even other Robins.

So it’s no surprise to learn that Robins have will attack red objects thinking they are intruders.

Another common habit of aggressive Robins is for them to attack their reflection in your windows.

3. Blue Jay

They may look sweet, but Blues Jays are one of the most aggressive backyard birds.

You’ll see Blue Jays dive-bombing other birds, preventing them from eating, stealing food, and attacking nests.

Blue Jays can even mimic the call of intimidating birds such as hawks to scare off other birds.

Basically, they’re little sociopaths and smart as heck too.

Why are Blue Jays Aggressive birds?

A blue jays aggression is territorial. This means their main aim is to intimidate other bird species rather than attack other blue jays.

They’ll bully their way into an area by dominating food supplies and destroying nests.

If that doesn’t work, they are pretty savage and will kill other birds if they have to.

Female Blue Jays can be as aggressive as male Blue jays.

4. Starlings

Starlings are one of the species of birds that most bird watchers despise. Some will say they are the sky rats of the birding world.


Sbirdstarlings have a tendency to drive out native species in the area. And that’s not great news if you want to attract a variety of birds to your feeders.

You’ll find Starlings arrive in flocks, which means not only is there one aggressive bird, but a whole lot of them.

One starling would not be so annoying but a whole flock can be very intimidating and loud!

Why are starlings aggressive birds?

Starlings are an invasive species to the USA.

Europeans sent over Starlings to the USA in 1890. Ever since they have been trying to dominate and are doing a pretty good job.

Attacking other birds to overtake their nests is a well-known Starling trait. They do this to particularly loved species such as bluebirds and owls.

Starlings are very opportunistic so if you have a food source for them, they’ll take over it and stop other birds from feeding on it.

Having other aggressive species such as blue kays and woodpeckers can help you keep starlings at bay in your backyard.

5. House Sparrows

small aggressive bird

If there was a vote on the most common, aggressive small bird the outright winner would be the house sparrow.

Like starlings, these tiny little songbirds are a foreign species and destructive to native bird species.

Similarly, they steal nesting sites, destroy eggs, and decimate food supplies, even attacking or killing other birds.

If blue jays are the sociopaths of the backyard birds, then sparrows are definitely tiny psychopaths.

Why are Sparrows aggressive birds?

Sparrows are mostly aggressive in areas where humans are.

That’s because they don’t migrate too far and have learned to adapt to the easy food sources humans provide.

Yep, that means your bird feeders!

Once they have that nesting sweet spot they don’t want other bird species to muscle in on their good thing.

Sparrows are a prolific flock breed. That means they have to maintain that food supply and nesting space if they want their young to survive.

6. Crows

Thanks to Alfred Hitchcock’s hit move ‘The Birds’  Crows have a reputation for being aggressive birds.

You’ll see them carry out mobbing behavior which includes coordinated circling, dive-bombing attacks, and squawking.

Crows thrive on safety in numbers. Chillingly, a group of crows is known as a ‘murder’.


Why are Crows Aggressive Birds?

Crows won’t attack you without good reason. That usually means you’re threatening them by being too close to their nest during the breeding season.

Be Warned: If you’re ever attacked by a crow, they have facial recognition and are likely to do it again.

Crows are pretty hard on other smaller birds. They raid nests to eat eggs and nestlings. If the opportunity arises, they’ll eat an adult bird too.

Crows are well adapted to human living areas. If they know you have a good food source, they will dominate other small birds in your backyard to get to it.

7. Brown-Headed Cowbird

Cowbirds are a particularly aggressive species of backyard birds.

They are actually known as parasitic birds. That means they lay their eggs in the nest of other bird species.

Why are cowbirds aggressive?

Cowbirds aren’t actually aggressive to other bird species as adults.

You may find that surprising, but hear me out.

Being a parasitic species means they have to locate the nests of other bird species around them. If they scare off those birds from making nests, they can’t lay their own eggs in them.

Their main source of aggression is eating eggs and killing nestlings in bird nests to replace them with their own.

Cowbird chicks are aggressive from birth. They need to be because once hatched they’re competing for food and space in the nest with the chicks of the other species.

This parasitic behavior can cause other bird species to become very aggressive around cowbirds.

8. Grackle

Grackles are larger backyard birds that intimidate other smaller birds

They are loud and boisterous and gather in flocks to scare others in numbers.

These bully birds attack nests as well as kill and eat other birds such as sparrows.

Why are grackles aggressive?

Grackles are backyard birds that try to dominate to help their species survive.

Just like other bully bird species, grackles are opportunistic around humans and take most of what they can.

Go near their nest during the breeding season and you’ll find yourself on the end of a grackle attack.

9. Red-winged blackbird

This is a species I had considered leaving off this list of aggressive birds.


Well, red-winged blackbirds aren’t always aggressive.

In fact, they try to stay as neutral as possible and avoid confrontation with other birds most of the year.

Why are Red-winged blackbirds Aggressive?

Red-winged blackbirds are extremely aggressive throughout the breeding season. This is usually from May to July for the species.

The reason behind this is that red-winged blackbirds mate with around 10-15 females at a time.

That means one male red-winded blackbird is territorial and trying to defend all those nests at a time.

Most red-winged blackbirds will use posture and loud chirps to intimidate other birds.

Red- Winded Blackbirds show aggression to any animals that come nearby. That includes humans and even animals as large as horses!

10. Red-headed woodpeckers

The red-headed woodpecker is an aptly named hot head.

Red-headed woodpeckers are very quick to pick fights with any bird they lay their eyes on.

Why are woodpeckers aggressive?

Most woodpeckers are territorial, but the redheaded woodpecker is the worst.

They are highly aggressive to other birds. Cavity-dwelling birds such as chickadees, wrens, and bluebirds get it hard from them.

In fact, there is so much fighting between red-headed woodpeckers that they become solitary in winter. They want to protect any food they have gathered over the fall.

Red-headed Woodpeckers and Starlings are mortal enemies. Although the woodpecker will hold its own, starlings have the advantage of strength in numbers and overthrow them.

11. Northern mockingbird

Northern mockingbird aggressive birds

Mocking birds are a well-known aggressive bird species. Although this increase in the breeding season, this behavior occurs all year round for mockingbirds.

Mockingbirds are bold and will physically attack anything they see as a threat to them. They will attack other birds, dogs, cats, and even the occasional person.

Why are mockingbirds aggressive birds?

An interesting fact about mockingbirds is that they aren’t fussy about where they nest.

Why is that?

Well, they are so aggressive as a bird species that it doesn’t matter because they will defend it so heavily.

Mockingbirds aren’t social birds so females will attack other females and males will attack other males.

The good news is that mockingbirds are highly intelligent and likely to pick up on you being a food source. This means they are unlikely to attack you.

But do them wrong and they will hold a grudge against you, so be warned!

12. Tyrant Flycatchers

Tyrant flycatchers aggressive birds

If you didn’t pick it up from the name, the tyrant part sure gives away the aggressive nature of this family of birds.

Although there are over 400 species of flycatchers they all share this aggressive nature.

That means that if you spot any species of flycatcher in your yard, it’s likely they will be aggressive to other birds.

Why are flycatchers aggressive?

Flycatchers are highly intolerant toward other bird species. Especially during the breeding season.

These tiny birds will chase away much larger bird species. If display and noise doesn’t scare them off, then a flycatcher will physically attack the other bird.

Aggressive Backyard Birds FAQ

You may have noticed that some bird have been left off this list.

That’s not because they aren’t aggressive, but they simply didn’t make the cut of being most aggressive.

Let’s look at some of the most frequently asked questions on aggressive backyard birds.

Are Hummingbirds aggressive?

Hummingbirds are aggressive but mainly with other hummingbirds.

You’ll notice that hummingbirds get very territorial over nectar feeders.

So why is that?

Well in the wild nectar is only available in very small amounts. That means hummingbirds often have to fight over a flower to secure food.

Missing out on one plant often means they have to travel further to find another one.

They don’t realize that when you feed offer them nectar at a feeder that it has an endless supply. That is as long as you keep filling it.

Naturally, that makes hummingbirds not good at sharing feeders. They fight to keep other hummingbirds away from their good food source as their survival depends on it.

Hummingbirds will also squabble with other nectar-feeding birds such as orioles, chickadees, and finches.

Are Cardinals Aggressive?

Cardinals and flock birds and they aren’t particularly aggressive.

As with most birds cardinals do need to be aggressive at times. You’ll mostly find a male cardinal being aggressive during breeding season when he is are trying to defend his territory.

You may find cardinals being aggressive to your windows more than anything. This is because they think their reflection is another male bird.

Other than this cardinals are very social with other birds. They’ve even been known to join other species flocks.

Final thoughts

So now you know 12 species of aggressive birds you find in your backyard.

Some of these birds may be desirable to you so having them around isn’t such an issue.

Other birds such as sparrows and starlings are problematic birds and will overtake your feeders.

You don’t want to encourage these invasive birds to overtake an area or it’s unlikely you’ll get other bird species at your feeder.

Let me know in the comments which bird you find most aggressive in your backyard.

5 thoughts on “12 Aggressive Birds you’ll Find In Your Backyard”

  1. I recently started seeing these small birds going to my bird feeder and being very aggressive towards chipmunks and other birds, I was impressed by the way that they fight off anything and everything that tries to make it to the bird feeders. And it looks like it’s the house sparrows, they are afraid

    • I have had a catbird nesting in my yard in the same spot for 5 years . As soon as my cat goes out rhe catbird attacks like an M16 and funs back in the house. Is there any way to get rid of starlings and gackles?

  2. I live in the UK and here the House Sparrow is not known as an aggressive bird. The Starlings we see in our garden are frequently aggressive but only amongst themselves. In fact at the moment I’m watching Starlings and House Sparrows on our garden feeders quite happily together, which is a common sight for us.

  3. You forgot to mention the HOUSE WREN who every year destroys bluebird and chickadee nests and nestlings. And I have never seen a robin hurt another bird. They do puff up and protect their own but they do not hurt other birds so I am surprised you mentioned this. The catbird has destroyed 2 Phoebe nests in our yard.

  4. Great list! I would have put the Northern Mockingbird as number 1 though! They are super aggressive! But they’re kind of funny too. One in my area mimics car alarms and people always comment on it when they hear it, since they can’t believe the sound is coming from a little bird. lol. I don’t have any Blue Jays where I live, so maybe they could be worse, but we do have Western Scrub Jays, but they’re actually pretty friendly.


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