Juvenile Crested Eagle photo by Angel Muela
Did you Know?
- Juvenile Crested Eagles are sometimes mistaken for juvenile Harpy Eagles. Both species have similar coloration, share the same habitat and use the same trees for nesting. Adults of these two species are easier to tell apart, but still quite similar.
- The Crested Eagle is the only species in the genus Morphnus
How The Peregrine Fund is Helping
The Peregrine Fund has been studying wild Harpy Eagles in Darien, Panama for more than twenty years. While the focus of their work is on the Harpy Eagle, they are also working to understand and conserve other wild raptors, including the Crested Eagle. Our work in environmental education and community development in areas that surround Crested Eagle habitat also goes a long way in ensuring this lovely eagle's protection. We also supply literature to researchers from our avian research library, which helps scientists around the world gather and share important information on raptor conservation. And, we support the Neotropical Raptor Network, a listserv that helps researchers throughout the Crested Eagle's range learn from each other, collaborate with each other, and share information about raptor conservation.
Where It Lives
Historically, Crested Eagles were found from southern Mexico through Central and South America all the way down to northern Argentina. Sadly, like Harpy Eagles, they are likely disappearing from much of their historic range mainly because people are destroying their habitat and shooting them.
The Crested Eagle is a Neotropical rainforest species. It lives at low to sometimes mid-elevations where it can find prey and large trees for nests. Its rainforest home is lush and vibrant and contains some of the highest biodiversity in the world. It lives among jaguars, macaws, tapir, monkeys, sloths, snakes, frogs, and many other plants and animals – each one playing an important role in its environment. In French Guiana, biologists documented this large eagle in palm swamps. It is often found in areas near rivers.
What it Does
The Crested Eagle is a striking eagle. Males and females are similar in color, though, like in most raptors, the females are larger than the males. Like some birds of prey, the Crested Eagle presents in two different color morphs - a light morph and a dark morph.
If you find yourself in Crested Eagle habitat, keep your eyes open for a large bird perched high up in the canopy. If you spot a light morph individual, it will have a dark black back and wings, a slate grey head and upper breast band. Its lower breast will be white and streaked with thin, rufous barring.
If you happen to find a dark morph individual, it will be mostly black all over, though many dark morph individuals also have white, horizontal barring across their lower bellies. Both light and dark morph Crested Eagles have a crest that ends in a single pointed feather.
Like many eagles, the Crested Eagle likes to perch high up in the canopy deep in the forest or along forest edges. From there, it can survey the land and keep an eye out for movement below, which might signal an opportunity for food. This large eagle is not very vocal and, despite its large size, is often overlooked. Unlike the Harpy Eagle, the Crested Eagle does spend time soaring in the sky.
One biologist from The Peregrine Fund observed some seemingly unusual behavior between a Harpy Eagle and a Crested Eagle. This biologist, working in Panama, watched as an adult female Crested Eagle repeatedly brought food to a recently fledged Harpy Eagle near the Harpy Eagle's nest site. The biologist and his team watched as the Crested Eagle delivered snakes, squirrels, and sloths to the fledgling.
Why It Needs Our Help
The Crested Eagle is classified as Near Threatened by the IUCN. But what exactly does Near Threatened mean? Is this species in trouble or not? The short answer is "yes." Though the species isn't considered threatened now, scientists believe that if no further, immediate action is taken, it is very likely that its population will be in trouble in the very near future. So, what threats does this eagle face and why are biologists worried about its future? The biggest threat that the Crested Eagle faces is habitat loss, especially as forests are converted into agricultural fields or cattle pastures. Another threat is when humans shoot these beautiful eagles directly out of curiosity, out of fear, or because they think it will eat their domestic animals. One way you can help Crested Eagles is by learning as much as you can about them and sharing this with your friends and family.
What it Eats
If you guessed that a large bird like the Crested Eagle would feed on relatively large prey, you would have guessed right. But, it also takes some smaller quarry as well. This eagle uses its strong legs and sharp talons to capture its prey that includes birds such as guans and trumpeters, and medium-sized mammals such as small monkeys including Squirrel Monkey and young Spider Monkeys, as well as opossums and kinkajous. It will also take reptiles, including Rainbow Boa and Emerald Tree Boas and iguanas. It will also feed on amphibians such as frogs.
In order to catch such a wide variety of prey, it needs to employ different types of hunting techniques, depending on what it is hunting and when. It might perch patiently under or nearby fruiting trees, waiting for hungry guans or monkeys to come by to feed. Or, it might hunt by flying from perch to perch inside the canopy or at lower levels of trees, to see what it can scare up.
Nests, Eggs, and Young
The Crested Eagle builds quite a large nest. Their nest, built in the form of a huge platform, is made of sticks and is usually placed in the central fork of a large tree. When the time is right, the female will lay between 1-2 eggs, which are cream-colored and sometimes marked with pale brown and lilac-gray spots. Even though the female can lay up to two eggs, researchers have never documented a nest with more than one young at a time!
After the eggs are laid, they must be incubated for 40-50 days. The female spends the majority of her time caring for the eggs while the male is responsible for bringing her food. When the young nestling hatches it is covered in soft, pale down. However, it will grow quite quickly and at around 4 months of age it will be ready to fly from the nest for the first time.
Over those 100 days or so it takes to develop from a fluffy down-covered ball to a nearly fully feathered eaglet, the adult female remains very close to the nest. When the nestling is very small, it relies on it mother to help it stay at just the right temperature. To do so, the female covers the nestling with her body to make sure it doesn't get too cold, wet, or hot. This is called "brooding." As the nestling grows, the female will stay around to guard the nest and her young. During this time, the male needs to catch enough food to feed himself, the female, and the nestling. This is a lot of work. Because the eaglet grows so quickly, it needs to eat a lot and it needs to eat often.
When it is very young, the mother will tear off small pieces of meat brought to the nest by the male adult. She will delicately feed the young eagle with her beak. Later, as the nestling grows, it will be able to tear off and eat the meat on its own. After close to three months, the female will begin to venture further from the nest, as her young is now large enough to be relatively safe alone in the nest. At this time, both the adults will search for food to feed themselves and their quick-growing offspring. At around four months of age, the young eagle will fledge, or fly for the first time. Its first few flights might be shaky and awkward, but after only a few days, it will be flying almost as well as its parents.
The young bird will remain dependent on the adults for the first year and a half of its life. When it is hunting well enough on its own, the juvenile will disperse, or leave its parents' territory and look for a home of its own.
A pair of Crested Eagles generally raises young every two years. They normally won’t lay more eggs while they are still caring for a young bird in their territory.
Crested Eagles and the World Center for Birds of Prey
The World Center for Birds of Prey is a great place to begin learning about eagles. Though we don't have any Crested Eagles as part of our Avian Ambassador crew, we do have a live Harpy Eagle at the center. You can meet Grayson, a male Harpy Eagle, in his specially-designed chamber. We also have a live Bald Eagle and a young Ornate Hawk-Eagle on site. We have a mounted eagle on display, real Harpy Eagle feathers you can touch, and a short video that chronicles the exciting journey of our biologists as they work to conserve birds of prey in the dense forests of Panama.
References:
BirdLife International. 2017. Morphnus guianensis. The IUCN Red List of Threatened Species 2017: e.T22695991A118209977. https://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T22695991A118209977.en. Downloaded on 02 August 2021
Global Raptor Information Network. 2021. Species account: Crested Eagle Morphnus guianensis. Downloaded from http://www.globalraptors.org on 16 Jul. 2021
Smith, J. W. (2020). Crested Eagle (Morphnus guianensis), version 1.0. In Birds of the World (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.creeag1.01
