Facts About the Female Bald Eagle (With Pictures)

Female bald eagle up close

The female bald eagle is one of the most iconic and well-known birds across the country. Large populations of these majestic raptors can be found in numerous areas around America and Mexico.

Unlike other birds and different types of species, female bald eagles are relatively larger than males. Female bald eagles are typically around 43 inches tall, while males are only around 36 inches tall. 

Aside from their distinct size, the female bald eagle has multiple other interesting characteristics and capabilities. If you’re curious to learn all about them, this article features several interesting facts and more. 

What Is a Female Bald Eagle Called?

Two female bald eagles perched on a fallen tree

Generally, people typically refer to both female and male bald eagles simply as “bald eagles.” In other instances, female bald eagles, as well as hawks, are referred to as “formels.” 

The term formel was initially used in the poem “The Parliament of Fowls.” A formel was a female eagle that was sought after by three male eagles, also referred to as tercels. 

Young bald eagles, female or male, are referred to as eaglets or nestlings while they remain in the nest. Once they leave the nest and become capable of flying, they are then called fledglings. 

In the six months following the fledgling stage, where they begin to molt, they are then referred to as juveniles. The subadult stage follows and lasts for around four years before the female bald eagle becomes a full adult.

Female Bald Eagle Size and Weight

Similar to several other birds, female bald eagles are around 20% to 28% larger than male bald eagles. Females typically weigh around 15 pounds, while males only weigh around 13 to 14 pounds. 

Female bald eagles also vary in size depending on their location. Females located at lower latitudes, such as South America and southern Mexico, are smaller than females at the higher latitudes of North America and Alaska.

10 Interesting Facts About Female Bald Eagles

Female bald eagle mid flight

Let’s take a closer look at the female Bald Eagles, those magnificent birds soaring in our skies. Here are 10 interesting facts that reveal just how amazing and unique these powerful creatures really are:

1. Female bald eaglets leave the nest later than males

Several studies and observations focused on bald eagle nestlings have shown that male bald eaglets consistently leave the nest earlier than female bald eaglets, regardless of which egg hatched first.

Although there isn’t much information about why this occurs, it is believed that female bald eaglets require more time under parental care before developing the capability to fly independently.

2. They have unique bird calls

Several ornithologists and researchers have observed that female bald eagles breeding in captivity release a unique kind of vocalization that only females reveal under specific circumstances.

Bald eagle copulation begins when the nest is nearly finished. In a mating ritual, female bald eagles signal the male regarding their inclination to copulate by uttering soft and high-pitched calls. 

3. They select nesting territories

It has been observed that the female bald eagle selects and holds its territory firmly, especially if the environment and conditions are of high quality for itself and for its offspring. 

One study states an observation where although a female bald eagle lost two of its mates within two years, it remained in her chosen territory and brought a new set of mates instead. 

4. They have high levels of reproduction

Although there are few studies that highlight the reproductivity of the female bald eagle, a study in Alaska observed one female that successfully nested for 11 years and reared 23 young, which was around two per year.

Generally, effective mating to produce offspring is believed to take place around 4 to 10 days. The egg journey down the female bald eagle’s oviduct is only around three days before fertilization occurs and an egg is laid.

5. Female bald eagles usually initiate pair formation

Female bald eagles have been observed to swiftly initiate new mates and pairings once their most recent mates disappear. 

A female bald eagle in Ohio was studied and observed for eight consecutive years, wherein it selected and replaced four different male bald eagle mates because some either disappeared or passed away.

Another interesting observation in Arizona involved a female bald eagle that lost its mate during the incubation period. The female eagle only took one day to select, attract, and then replace the previous mate.

6. They occasionally assist other breeding pairs

Under rare and uncommon circumstances, the female bald eagle would join an existing breeding pair in order to help properly raise the pair’s offspring. The additional female eagle helps gather and deliver food for the eaglets. 

This usually occurs when one eagle from the original breeding pair cannot perform certain parental tasks due to injury or sickness. 

7. Their main responsibility is to protect their offspring

Several studies and observations have consistently shown that female bald eagles fearlessly protect and defend their eggs and their young under any circumstances.

Since female bald eagles are quite large compared to males, they can efficiently protect their young from other predators that typically attack their nests during the night. 

Although male bald eagles are also capable of doing parental tasks, females spend a larger amount of time incubating the eggs and brooding the eaglets compared to male eagles. 

8. They primarily handle parental care

As mentioned in the previous section, female bald eagles are focused on caring for their offspring. Unlike males, females typically perform more parental tasks during the first 2 to 3 weeks of the eaglets’ lives. 

During the initial stages of the nestling’s development, the female bald eagle is at the nest around 90% of the time, while the male eagle is at the nest around 50% of the time. 

My friend, who has worked in a conservatory catering to bald eagles, has observed that females brood their young during cold and continuously changing weather conditions until they are around four weeks old.

This supports the studies showing that female eagles brood around 65% during the day and males 35%. 

9. They can replace lost eggs quickly

Several studies and observations have shown that female bald eagles can quickly replace lost eggs. Once they lay all their eggs and lose a few to natural causes, female eagles will likely lay another batch shortly after.

Female bald eagles are typically able to replace lost eggs swiftly due to their high reproductive levels and ability to find, select, and attract new mates within short periods. 

10. Female bald eagles have a well-developed brood patch

A brood patch is an area on the female bald eagle’s chest that does not have feathers. This is the area that comes in contact with the eggs during incubation, which allows a more efficient way to keep the eggs heated. 

Since both female and male bald eagles have brood patches, both are capable of incubating eggs. Considering that the female spends more time brooding eggs, its brooding patch is more developed than the males. 

Bald eagles used to be difficult to spot since they were initially hunted for sport. Over the years, they have become a national symbol for animal conservation and can now be found in several areas across America. 

Check out the video below to get a closer look at what a female bald eagle looks like:

Female Bald Eagle Up Close

Do Bald Eagles Females Have White Heads?

Since female and male bald eagles often look extremely alike, they invariably have white heads and rarely exhibit differences in head or body colors. 

Generally, the vast majority of male and female birds across different species have similar appearances that make it difficult to tell them apart. In most species of birds, males have more colorful features than females.

Some people have assumed that female bald eagles have pure brown heads instead of white. This theory is false, as brown bald eagles are actually juvenile or young female eagles that have yet to fully grow and mature. 

How to Tell the Difference Between a Male and a Female Bald Eagle

Since male and female bald eagles have extremely similar physical features, it can be very challenging to distinguish one from the other. The main factor that differentiates the two is their size and wingspan. 

The wingspan of a female bald eagle can reach up to 86.4 inches, while the wingspan of a male bald eagle can reach up to only 76.8 inches. 

Bald eagles from the same area and latitude typically have the same size. Hence, female bald eagles are consistently larger than males when the comparison is made in the same specific latitude and location. 

Female bald eagles can grow up to 43 inches tall and can weigh around 15 pounds, while male bald eagles typically grow up to only 36 inches tall and weigh around 13 to 14 pounds. 

When eagles are from different unknown areas and latitudes across the globe, size may not be the most reliable way to differentiate the males from the female bald eagles.

Aside from their size, weight, and wingspan, there are other subtle differences in their appearance. These include the females’ rear-facing hallux toes being larger and their beaks slightly deeper than the males’. 

Frequently Asked Questions

Female bald eagle screaming

Do Male and Female Bald Eagles Look the Same?

Male and female bald eagles typically look extremely alike. Their differences include weight, size, wingspan, the size of their hallux toe, and the deepness of their beaks. 

Do Both Male and Female Bald Eagles Sit on the Eggs?

Generally, both male and female bald eagles have brood patches that give each of them the ability to incubate or sit on their eggs. 

Since female bald eagles spend significantly more time in the nest nurturing and protecting their eaglets, female bald eagles brood and incubate eggs more than males. 

Are Female Eagles Stronger Than Males?

Considering the large difference in size and wingspan between the male and female bald eagles, female eagles tend to be quite stronger than males. Their larger size and wingspan pose an advantage when defending the nest. 

Why Are Female Eagles Larger Than Males?

Female bald eagles are larger than males due to the reversed sexual size dimorphism (RSD). This occurs because female bald eagles perform more parental roles, such as incubation and protection. 

If you’ve encountered a female bald eagle before, we’d love to hear all about your experience in the comments below! All questions regarding female bald eagles are also welcome. 

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