Hawks fly in circles because they utilize a natural phenomenon known as thermals. These are columns of rising air, which allows hawks to stay in the air with using energy.
Hawks are known for their aerial acrobatics, and one commonly asked question is why they do circles before swooping down on their prey.
There are a few different theories out there, but scientists have figured out that the answer is thermals.
In this post, we’ll take a look at thermals, what they are, and how hawks take advantage of this natural phenomenon.
Why Do Hawks Circle?
Hawks circle because they’re waiting to strike. They use thermals, naturally occurring columns of wind, to keep them airborne, allowing them to conserve energy while scouting.
Firstly, it allows them to conserve energy while looking for an opportune time to strike. By circling above their target they can time their attack, making sure they have the energy to carry out a successful kill.
Hawks’ preferred hunting technique is a dive at high speeds, which takes a great deal of effort for the hawk and puts it at risk of injury. By staying in the air and circling, they can be certain their prey won’t get away and that they don’t waste any precious energy on a failed hunt.
They can stay in the air for a long time due to thermals, as a natural phenomenon explained later in this article.

Why Do Hawks Screech While Circling?
Most birds produce noises for the following reasons:
- Signal danger or distress
- Attract attention
- Communicate
But if hawks are trying to intimidate prey or communicate with each other why do they screech while circling?
Hawks, and other territorial birds, make loud noises to claim territory. It’s a warning sound for other birds of prey to stay out of their territory.
By being loud and aggressive, they are sending signals that challenge the other birds in order to maintain dominance.
Hawks also often keep in groups and will circle together. This behavior is why you sometimes see multiple hawks circling an area or why they often change positions as they circle.
They are likely working as a team to keep the prey from moving and protect their food for themselves.

What Is a Thermal?
A thermal is a column of warm air that rises from the ground. This causes a vacuum in the surrounding area, and thus an area of low pressure is created which allows for air to be drawn into it[1].
In other words, a thermal is a column of rising air, where hot air is present at the bottom of the column, and hot air is expelled from the top.
Hawks use these thermals to climb higher into the sky, where they can fly with less effort.
Once they find an updraft, they will circle the thermal in order to gain altitude. They move gracefully and effortlessly compared to when they fly on a horizontal plane because they are effectively being lifted by the updraft.
Hawks use this thermal phenomenon to catch prey more effectively, as hawks can easily cover more ground from higher altitudes. They also spend less energy flying up.

How Are Thermals Made?
Thermals require two things: contrast in temperature (hot and cold air), and some form of accelerator.
The temperature differences come from the sun. As the ground is heated up by the sun, it’ll warm up the air above it. If this happens quickly, it’ll create a sharp contrast between the hot air and cold air.
The presence of proper acceleration is also needed, such as wind.
Where Do Thermals Occur?
Thermals can occur anywhere on Earth, but they are most common over land, where the sun’s rays are more concentrated. This is because the land heats up and cools down faster than water, and the resulting currents of air can rise to be taller than on water’s surface.
Why Do Hawks Use Thermals?
Hawks use thermals to conserve energy. It’s a more effective way of staying in the air, as they don’t have to flap their wings. The column of rising air carries them.
The one major way in which hawks differ from many other animals is their ability to soar.
Other animals like eagles also use thermals while hunting, hence the skill of soaring is not exclusive to these birds of prey.
Hawks spend a great deal of time just gliding, rarely flapping their wings[2]. By using thermals, they can reduce their energy output.
Related: How do hawks attack and kill their prey?

What Does It Mean When a Hawk Is Circling?
When a hawk circles above something, it typically means the hawk is either searching for food or looking for a mate.
Hawks circle primarily for scouting. This can either be to find food, a mate, or competitors.
If a male hawk sees another male trespassing on its territory, the two males may engage in a mid-air battle to determine whose territory it will become.
Their incredible vision, which is 4 to 5 times stronger than that of a human, they can see very far when circling in the air.
Hawks sometimes circle above trees to survey their territory, especially if there are eggs in their nest.

Why Do Hawks Circle in Groups?
Hawks are social animals. They live and hunt in pairs, which is why they circle together.[3]
Hawks live in pairs. They’ll mate, hunt together, and sleep in the same nest. This is the social nature of hawks.
Hence, as they hunt in groups, they also circle in groups. This gives them an advantage, as four eyes are better than two.
What Attracts Hawks?
Hawks are attracted by food. They’re opportunistic feeders, and hunters, meaning they’ll take advantage of whatever they can find, whether it be mice, songbirds, or dead animals.
Hawks are hunters by nature, which means use their maneuverability to catch live prey. They’re great hunters as well, utilizing their speed, vision, and sharp talons to catch prey.
Their vision allows them to precisely calculate how their prey moves, allowing them to sneak up on their prey and hit them with pinpoint accuracy.
Hawks aren’t very big, and can hence not prey on animals such as raccoons, foxes, or any medium-sized mammals.

How Long Do Hawks Stay In One Area?
A hawk can stay in one place for a few hours. By soaring through the air, conserving their energy, they can fly for 4-5 hours at a time without rest.
Hawks are very patient animals. If they catch onto prey in an area, they may stick around for a few hours.
If nothing happens, they will likely leave to find better hunting areas or to take care of other businesses. When hawks are not hunting, they are protecting their nests.
Hence, if you’re dealing with a hawk around your house, you just have to be patient.
Why Do Other Birds Not Circle?
Hawks are some of the most magnificent bird species on Earth. They have the ability to soar effortlessly through the sky, propelled by rising thermal updrafts.
Many other birds cannot do this, because they do not have a wingspan that allows them to catch these thermals.
These birds are not strong enough to catch thermals, so they must flap their wings or ride on the wind in order to move through the air.
Some birds can’t soar through the sky but must flap their wings continuously.
Conclusion
Hawks circle their prey to time their attack. They might do this for hours before finally swooping in and making a kill. They are able to circle for a long time by utilizing the natural phenomenon known as thermals.
Thermals are columns of rising air, which occurs when hot and cold air collides, combined with an accelerator. Hawks use these columns to rise up and stay in the air without spending much energy.