Given that crows are so much smaller than eagles, you might be tempted to think eagles would be more dominant…
But if you’ve ever watched a group of crows wildly chasing and dive-bombing an eagle through the sky, you know it doesn’t always work that way!
Eagles are sometimes seen as royalty of the bird kingdom, so why would a smaller bird like a crow put their life in danger and chase the much larger and threatening eagle?
Why do crows chase eagles? Crows do this to protect their nest site from possible danger. They will also steal food from eagles in places where their feeding territories overlap.
Of course, to really understand why Crows are able to get away with such a risky behavior, we need to do a more detailed comparison of crows and eagles.
This is a great way to gain deeper insight into the lives of two incredibly fascinating birds.
So let’s take a look at the unique behavior of crows and how their social intelligence gives them the edge against larger predatory birds like eagles.
We’ll also go over some tactical & strategic differences that cause eagles & crows to handle these situations in different ways.
Crows VS Eagles Social Behavior
One of the big reasons why crows can get away with chasing eagles is because of significant differences in their social behavior.
Crows are unique within the bird community for a number of reasons, however their social behavior is one of the most important.
Crows are rarely alone and tend to have much closer family ties than other songbirds or even predatory birds.
During the core nesting season, crow families are made of a mating pair like all birds, yet they’re often also assisted by non-mating juveniles from the previous year.
This means they live and socialize with much larger and tighter groups than other birds.
When nesting is finished for the year, sometimes crow families will join with even larger communal groups that can reach more than a thousand crows.
Their strength comes from numbers, so they travel and live in flocks, often teaming up to chase away threats, or steal food from other birds like eagles.
This gives them an obvious advantage against more solitary birds like eagles.
Eagle Social Behavior
Eagles can also sometimes be found gathering in large groups, but it’s not such a core part of their life strategy as it is with crows.
Typically when you see large numbers of Eagles gathering together, it simply means there’s a particularly abundant food supply, like a salmon run.
Eagles nest in solitary pairs, and they typically have quite large territories that are well defended against other Eagles. They seem to rely more on their size and strength to keep their boundaries rather than social skills.
This defence strategy works well against other large soaring birds, but it’s actually a disadvantage when it comes to crows, who have the edge in both numbers and speed.
With enough harassing and chasing, Eagles are relatively defenceless against large gangs of crows.
In places where their territories overlap, it’s quite common to see Eagles swooping down to catch a fish, only to have it snatched away by a group of crows.
Without any other Eagles around to help in the fight, there’s often no other choice but to go back and catch another meal.
Interestingly, ravens have similar problems when it comes to defending their territories against crows because although they have similar intelligence, ravens are also much less social.
Crows VS Eagle Habitat
As mentioned above, crows don’t like to be alone because their strength comes in numbers. They stay in flocks and can be quite aggressive against intruders.
In my article on the crow diet, we also discovered that crows are highly adaptable omnivores who can live in a wide variety of environments, sometimes with dramatically different food sources.
Crows are what wildlife trackers sometimes call an “edge species”.
This means they thrive in places where you have dramatically different landscape types bumping up against each other (like the edge of a forest next to an agricultural field).
This gives the crows a sheltered spot to hide their nest, while also providing access to more diversity of food by capitalizing on multiple ecological zones.
It’s interesting to note that as human activity has gradually transformed massive unbroken forest landscapes into patchworks of lawns, parks, farmlands & garbage dumps, crow populations have significantly increased.
Another type of edge habitat where crows thrive is the border between forest/field and water, which is exactly where they tend to bump into eagles.
Eagle Habitat
Bald eagles are found throughout North America. However unlike crows, they tend to prefer less urban areas, and have a very strong association to bodies of water.
In a way this means Eagles are also very much an edge species, but they simply have much more restricted habitat needs because of their fishing preferences.
Crows will occupy pretty much any edge habitat, but Eagles really prefer having access to big trees and water together.
They will of course take the opportunity to eat land-based creatures like squirrels, rabbits or other smaller mammals when the opportunity arises, but the main staple tends to be hunting on water and eating fish.
Since crows also enjoy living in the edge zones between water and land, they tend to bump heads frequently in these particular landscapes.
This is really where all the interaction between crows & eagles takes place.
Some families of crows will be observed interacting with eagles on an almost daily basis, while more inland families might almost never encounter eagles.
How Eagles Kill Their Prey
Bald eagles are at the top of the bird charts in terms of size and power, so it’s natural that they would be a predator.
The bald eagle uses it’s talons to kill it’s prey, however their skill comes from swooping in unexpectedly from above, rather than speed or agility.
The eagle will pick a perch next to the river or lake to scope things out.
They have incredible eyesight and even have the ability to visually “zoom in” on things they want to see more clearly.
When hunting, you’ll often see them choosing a high perch where they can sit and watch from above looking for opportunities.
Then when they’re ready to catch a fish, they simply swoop down and pluck their target from the water.
This video shows how genuinely skilled the bald eagle is at catching fish.
However it also highlights a significant weakness that crows are able to exploit…
The Eagle’s hunting skills come from above, so as long as the crows don’t drop below the eagle, there’s not really much the Eagle can do.
Why Crows Attack Eagles
Crows attack Eagles for 3 main reasons.
1. Food Stealing
Probably the most common reason crows attack eagles is to steal food. If you ever get a chance to watch an Eagle hunting as in the above video, pay attention for whether you notice any crows in the area.
See if you can watch what happens after the eagle catches its meal. Where does it go? How far can you follow and keep track of the movement?
If you pay attention, sometimes you’ll hear crows sounding an alert call. They may fly in from various directions to begin dive-bombing the eagle & harassing it in order to steal the food.
However, it’s not just the crows who threaten the Eagles. Eagles can also be a serious threat to crows, especially during the nesting season.
2. Nest Defence
Just as the crows might steal food from eagles, sometimes eagles will go after a baby crow or young nestlings.
Eagles are known to be nest robbers of large birds like crows.
When the opportunity presents itself, the will go after a crows home and eat the eggs, nestlings, or juvenile fledglings.
The main safety net crows have against the bald eagle is their community, speed, and ability to stay above the eagle during encounters.
3. Competition For Nest Sites
A third possible reason why crows sometimes attack eagles is during competition for nest sites. This would only happen during the early nesting season, usually around late winter.
Eagles & Crows sometimes have very similar nesting preferences.
In landscapes where you have an abundance of food, yet limited nest sites, these locations come into high demand causing competition between various types of raptors, eagles, crows & ravens.
Here again the crows have a definite edge because of their aggressive social tactics that endlessly harass or chase until the competition has to give up and turn back.
Crow Tactics Against The Bald Eagle
In one-on-one disputes with crows, an eagle would definitely have the advantage.
However, crows are usually able to overcome the size & strength disadvantage by using several highly intelligent tactics that combine social skills with smarts.
1. Synchronized Attacks
With the way Crows travel in groups, they’re kind of like the hyenas of the bird kingdom.
Their small size and inferior strength is not a recipe for great hunting skills, however teaming up with others they are quite capable of stealing fresh meat from more capable predators.
If you ever watch crows chasing an eagle through the sky, you might notice they take turns dive bombing, sometimes from a variety of directions (though always coming from above).
Having synchronized attacks makes it significantly more difficult for the Eagle to defend itself.
Without a single target to focus on, the Eagle becomes confused and loses the focus normally required to effectively catch prey.
This is very similar to how hyenas manage to steal scraps of fresh meat from lions by moving in at multiple angles simultaneously.
2. Determination & Morale
Another common tactic used by crows is their sheer force of determination.
Quite simply, their numbers enable them to be more persistent, at times perching above a hawk, owl or eagle for what seems like hours in a mobbing behavior.
Mobbing allows the crows to attack or fight off much larger predators by banding together and cawing at them incessantly.
This tactic can be highly effective as the predator is intimated by not only the noise of loudly cawing crows, but also the shear number of birds in its vicinity.
If you count the number of crows present during mobbing behavior, you’ll notice sometimes it ranges from as little as 3 or 4 crows, all the way to dozens at a time.
This is one way crows are able to keep so much pressure on a predator for so long. While some of them are mobbing, others are off feeding & replenishing, then they can switch out and the eagle gets no break.
This is a huge advantage that eventually often results in the crows coming out on top.
Why Don’t The Eagles Fight Back?
Eagles are considered one of the largest predators within the bird kingdom. So why don’t they fight back when crows attack?
Well, they actually do sometimes!
Bald eagles have been known to kill and eat not only younger crows, but also fully developed adults.
If crows get too cocky and take extra risks, or get caught in a one-on-one battle against an eagle, it is possible for them to mis-step and get taken by a sudden reflexive grab of the Eagle’s talons.
In the harsh reality of nature there’s always a potential risk when taking on such a dangerous competitor. This is one of the reasons why crows will only go after eagles as long as it’s absolutely necessary.
All animals have the survival instinct to try and avoid conflict whenever possible. As soon as the risk no longer outweighs the reward, crows will leave the eagle in peace and turn their attention to other things.
The same is true from the eagle side of things.
When crows use mobbing tactics, eagles will typically do their best to steer clear and escape. However like the crow, they always welcome the opportunity for an easy meal when it arises.
Diana says
Great post! I learned a lot about crows AND eagles from this. Strength-in-numbers is the crow species’ best friend, it seems, so I will be on the lookout for families or large murders in the future to see what they are up to. Also – so interesting to hear and see more about eagles’ hunting style.
Brian Mertins says
Thanks Diana, I agree it’s such fascinating stuff. The closer we look, the more connections there are to discover!
Oladejo Olalekan says
This is beautiful!
Can we say this is a kind of biological association!
Like we have in remora and shark
Brian Mertins says
Yes, I’d say there are similarities here.
MTR says
Absolutely amazing post. I really learnt a lot of things I never knew. Thank you.
Brian Mertins says
Thanks, glad you found it helpful!
Taiwo Olatokunbo says
So interesting couldn’t stop till the last word,great piece.
Brian Mertins says
Thanks Taiwo, glad you enjoyed it!
Madonna says
Wow its so amazing, I learnt a lot, never new there is a bird that can steal from eagle, kudos to crows
Caleb says
Wow. Great piece! Didn’t even know there was any bird that dares the eagle
rex says
I live on a forested cliff above the Puget Sound in Seattle, and we see crows mobbing eagles every day (in fact it’s happening right now out in front of my window as I type this). This article was fun to read!
You wrote: “crows will only go after eagles as long as it’s absolutely necessary”. It seems that my local crow tribe goes after eagles whenever they feel like it. Maybe in their eyes it’s “necessary”, e.g. “that’s the mofo who ate Vader’s kids! Get him!”
If only the crow/eagle tribes could hold a peace summit. “We (Eagles) will leave your nests alone, and you (Crows) will cease the mobbing and leave us alone.”
Brian Mertins says
Haha yeah thanks for sharing that Rex. In places where there are high population densities of crows and eagles, their mobbing & chasing events will happen very frequently.