There are a number of birds that will chase or harass hawks in order to defend their territories or protect their young. The most well-known bird that actively mobs and chases hawks is the crow. Crows are highly intelligent, social birds that work together to drive predators like hawks away. Other birds like blue jays, falcons, and small songbirds may also chase hawks, but crows are particularly aggressive and persistent in mobbing hawks.
Why Do Crows Chase Hawks?
Crows chase hawks for a few key reasons:
- To defend their territory – Crows are highly territorial and will work to drive any potential predators, including hawks, out of areas they claim as their own.
- To protect eggs and young – Crows nest earlier in the spring than many other birds, so will aggressively chase hawks and other predators that may threaten their eggs and baby chicks.
- Harassment and stress – By constantly dive bombing and mobbing hawks, crows can stress the hawks and make it harder for them to effectively hunt for food in the crows’ territory.
Crows may pick out individual hawks to harass repeatedly. Their attacks are both a warning and a way to try to actively drive hawks away from their nesting and feeding grounds.
How Do Crows Mob Hawks?
When a crow spots a hawk, it will call loudly to alert other crows. The crows will then gather and surround the hawk. Here are some of the mobbing tactics crows use:
- Dive bombing – Crows will dive bomb the hawk from above, often aiming for the hawk’s back or head area.
- Chasing – Groups of crows will chase after hawks, staying on their tail to drive them away.
- Loud calls – Crows give loud alarm calls during the harassment, both to alert other crows and to stress the hawk.
- Feigning injury – Crows may pretend to be injured to draw the hawk’s attention, then attack when the hawk gets close.
Mobbing by a large group of crows can be intimidating and dangerous for hawks. The crows take turns diving, calling, and chasing the hawk until it leaves the area. Some hawks may become accustomed to crow harassment, but crows are persistent and will still work to drive hawks away.
What Other Birds Will Chase Hawks?
While crows are the most well-known hawk harassers, other birds will mob potential predators as well:
Blue Jays
Like crows, blue jays are intelligent, social, and aggressive when defending territories. So they will gather to mob hawks using loud alarm calls and dive bombing attacks. Their sharp warning calls alert other birds to danger.
Small Songbirds
Smaller songbirds like robins, sparrows, and even hummingbirds may work together to harass hawks. They typically can’t dive bomb like crows, but will chase after hawks while making loud alarm calls, sometimes pecking at them.
Peregrine Falcons
The peregrine falcon is a predator, but still doesn’t tolerate other raptors hunting on its territory. Peregrines will chase larger hawks and eagles that stray too close to their nesting sites.
Sea Birds
Shore birds like gulls and terns nest in large colonies and will mob hawks or other predators that get close. They’ll surround the predator, calling loudly. Some may dive bomb like crows.
Ravens
Ravens are close corvid cousins of crows, so they may work to chase hawks away using loud calls and aerial attacks. Typically ravens are more likely to harass larger hawks while ignoring smaller ones.
Other Small Falcons
Kestrels and merlins are small falcon species that are natural predators of songbirds. Still, they may help chase and harass buteos (soaring hawks) to try to protect their own territories.
Do Hawks Ever Successfully Hunt Despite Harassment?
The mobbing behavior of crows and other birds does decrease the hunting success rate for hawks. However, hawks are still able to catch prey, especially if their attack is swift and the prey is out in the open. A 2011 study published in Animal Behavior looked at how crows impacted red-tailed hawk hunting. Some key findings:
- Crows disrupted 20-40% of hawk hunts.
- Hawks were still successful in 26% of hunts after being mobbed.
- Crows couldn’t stop hawks from catching exposed prey quickly.
- Harassment was more effective against young or passive hawks.
So while mobbing certainly has an impact, hawks have adapted to still be able to hunt successfully despite crow harassment. Crows can’t be everywhere, so hawks may focus on hunting on the fringes of territories or striking before crows respond. Hawks may also target prey when crows are busy doing other activities.
Do Hawks Ever Hunt Crows?
While mobbing does carry some risk, most hawks do not actively hunt healthy adult crows, for a few reasons:
- Crows are intelligent, crafty, and difficult to catch.
- Crows stay in tight groups, so are risky for solo hawk attacks.
- Adult crows are large enough that many hawks can’t physically overpower them.
- Crows aggressively fight back when attacked.
However, crows are still vulnerable when:
- Young, inexperienced crows stray from the group.
- Molting crows can’t fly as well to evade attacks.
- Stronger raptors like eagles may be able to catch exposed crows.
- Crows are busy nesting and can’t fully focus on defense.
So healthy crows are generally avoided, but younger, weaker or isolated crows may become hawk prey at times. The constant mobbing by crows makes the energy expenditure and risk of injury too high in most cases for hawks to actively try to hunt them.
Notable Examples of Hawks Hunting Crows
Red-Tailed Hawks
Red-tailed hawks are one of the most common North American buteos, or soaring hawks. They are large and powerful enough to potentially take down an adult crow, but usually avoid tackling them.
Cooper’s Hawks
These woodland hawks are crow-sized, so not able to overpower healthy adults. But they are adept ambush hunters, so can snag younger crows.
Northern Goshawks
Goshawks are fierce accipiters that have been documented preying on large numbers of crows during irruptions when food was scarce.
Great Horned Owls
As nocturnal ambush predators, Great Horned Owls take more crow prey than typical day-hunting hawks. Their stealth helps them seize crows at night roosts before the flock can mob them.
Golden Eagles
With their large size and power, golden eagles are capable of taking crow prey, even grabbing them mid-flight. But eagles rarely specifically target crows.
Peregrine Falcons
Blazingly fast peregrines can snatch unwary crows in mid-flight with their stoop attacks. But healthy crows mobbing in a group are too difficult for them.
Other Hawks
Sharp-shinned hawks, Harris’s hawks, and zone-tailed hawks may occasionally prey on young or injured crows when the opportunity arises.
Do Crows Sometimes Kill Hawks?
It is rare, but there are occasional reports of crows killing hawks during intense mobbing:
- In 2005, a group of crows in Massachusetts killed a juvenile red-tailed hawk by dragging it out of a tree and pecking it to death.
- A 2021 report described crows fatally attacking a juvenile Cooper’s hawk, with the crows removing feathers and flesh.
- Videos show crows pecking into the bodies of hurt hawks, though the full context is not always clear.
In these cases, the young hawks apparently became disoriented or exhausted, allowing the mob to overwhelm them. Most evidence though shows crows harassing rather than intentionally killing hawks. The hawk deaths are likely rare accidents rather than deliberate killing.
Do Hawks Ever Kill Crows?
While not common, there are certainly verified reports of hawks killing and eating crows:
- Red-tailed hawks and Cooper’s hawks feeding on crow prey have been photographed.
- Dissections of goshawks show parts of crows (bones, feathers, bands etc) in about 1% of their diets.
- Reports document great horned owls taking crows from night roosts.
- Golden eagles and peregrine falcons have been seen killing crows mid-air.
The evidence indicates most hawks will opportunistically grab crow prey when it is vulnerable, despite the risks of mobbing. However, specifically hunting adult crows in large flocks is usually avoided.
What Are Signs of Hawks Hunting Crows?
Some indications a hawk may be actively targeting and hunting crows include:
- A hawk patiently watching and following a crow flock.
- A hawk making quick dives at crows despite mobbing.
- Caws and mobbing growing more panicked as hawks zoom in.
- Hawk attacks focused on stray young or molting crows.
- Presence of crow feathers or remains in a hawk’s nest.
- A hawk returning to hunt an area where it caught a crow before.
Seeing these signs could mean a bold or hungry hawk is trying to overcome crow defenses to seize a meal. Smart crows may try to draw the hawk away from their nesting area by mobbing it further away.
Can Hawks & Crows Coexist?
The relationship between hawks and crows is complex. The two species face an evolutionary arms race:
- Hawks are adapted to hunt birds like crows for food.
- Crows have evolved mobbing as a key defense against raptors.
- Hawks try to find workarounds to still catch prey amidst mobbing.
- Crows respond by modifying their mobbing strategies.
This constant back and forth has led to a dynamic coexistence between the two groups. Both have evolved strategies allowing them to still gain food and resources despite the harassment. Some signs they have struck a balance:
- Mobbing is aggressive but rarely fatal for either side.
- Hawks continue hunting other prey even when frequently mobbed.
- Crows are watchful but generally don’t abandon prime territory.
- Attacks typically focus on vulnerable juveniles over healthy adults.
This stability allows both hawks and crows to maintain stable populations by adapting to the presence of the other. So despite the high drama, both species ultimately benefit from the unique interaction.
Conclusion
In summary, the crow is the bird most strongly associated with mobbing and harassing hawks. Crows aggressively work together to chase hawks from their territories and protect their young. Dive bombing, loud calls, and persistence are key crow tactics. While disruptive, mobbing doesn’t fully deter hawks from hunting.
Hawks opportunistically grab crow prey when possible but mostly avoid wasting energy trying to hunt intelligent, numerous crows. This gives crows safety in numbers. Both species have struck an equilibrium that enables their coexistence through adapted strategies. So this conflict is more a controlled burn than a raging fire, allowing both crows and hawks to flourish.