AEF Bald Eagle Captive Breeding Status

Bald eagles are experiences one of their best captive breeding years at the American Eagle Foundation (AEF) of Pigeon Forge, TN.  Six bald eagle pairs have produced 14 eggs, of which 12 could hatch after 35 days.  The eaglets will be placed in AEF’s Douglas Lake hack tower at 6 to 8 weeks age.  The 25-foot high hack tower has four hack cages.  Each cage is  8x8x8-feet and can accommodate up to 3 eaglets at a time, or a total of 12 in all four cages.  The eagles will be released at approximately 13 weeks age, when they will be first capable of flight.  They will already have a full adult size, with a wing span of 6.5 to 7.5 feet.

As of March 27, 2011, each bald eagle pair had produced the following results and prospects (watch for updates):

  1. Sarasota, FL Wild Nest – On 12/13/10, 2 eggs transferred to an AEF incubator from a light pole platform at a Sarasota, FL baseball stadium.  One egg hatched at AEF on 12/29/10; other egg infertile.  Eaglet fed with puppet until moved to hack cage at 6.3 weeks age.  Release expected late March.
  2. Peace & Faithful –  2 eggs found on March 1 and 5, but later egg was broken.  Hatch expected about 4/5/11, with release near July 4.
  3. Brave Heart & Honor – 3 eggs found March 1, 5, & 7.  Releases expected near July 4.
  4. Freedom & Faithful Spirit – 2 eggs found March 5 and 11.
  5. Medina & Un-named male – 2 eggs found March 18 and 21.
  6. Independence (formerly called Bonispae) & Franklin –  Nest on live nest cam at  3 eggs found – March 23 , 26, & 29.  First egg temporarily moved to AEF incubator due to nearby construction.  Hatch expected about April 27 and 30.  Eaglets to be transferred to hack cage by 6 weeks age and released by late July.

About Bob Hatcher

Primary Blog Contributor, American Eagle Foundation
This entry was posted in Am Eagle Foundation Activities, Nesting - Live Cam, Propagation/Hacking/Releases. Bookmark the permalink.

6 Responses to AEF Bald Eagle Captive Breeding Status

  1. Darlene Mortenson says:

    I know that the sexual maturity begins around the age of 5yrs. old for a female bald eagle. But no where can I find anything stating when the end of a female bald eagles reproductive years are. I’ve spent hours upon hours searching for this information but to no avail. Could you help me?

    I believe in the wild since they have a life expectancy of approx 20-30yrs. (optimistically) it could be until the end of life.
    But in captivity, since they could reach as old as 50yrs. (under optimal conditions) at what age would the female cease to be fertile?

    Thank you for any direction or help you can offer me.

  2. Bob Hatcher says:

    Bald Eagles may theorectically lay fertile eggs as long as both adult eagles are healthy. However, if Liberty and Justice, two non-releasable Bald Eagles at the American Eagle Foundation (AEF), are an example, the chances of fertile eggs may begin to decrease between ages 15 and 20. Liberty and Justice bonded as a pair in 1993, when they were at least five years of age. From 1993 through 2004, they successfully raised 13 of their own offspring, an average of 1.2 per year, for release into the wild from a Tennessee hack tower. Their three eggs were infertile in 2005, when they were at least 17 years of age. Bad weather caused the collapse of their nest and loss of three eggs in 2006. Their one egg in 2007 was infertile. In 2008, one of their two eggs hatched, and they successfully raised the eaglet. They laid three eggs in 2009 but none hatched. Their two eggs did not hatch again in 2010. They could not nest in 2011 due to an injury prior to the nesting season.

  3. Robin says:

    So the young eagles (up to 3 of them) @ approx. 6 weeks old are put in an 8x8x8 enclosure & are then released at around 12 weeks old. What about branching? I understand they first learn to hop around & flap their wings, then graduate to hopping on nearest branches, then back to nest again…over & over again before flying. An 8x8x8 enclosure sure doesn’t sound adequate for that part of the growing up process & removing them from the parents @ 6 weeks old to put them in this enclosure sounds cruel. Of course they have no choice in the matter & I think the whole system sounds inhumane.

    • Bob Hatcher says:

      Robin, thanks for your comments and inquiry about bald eagle hacking procedures. Eaglets are taken from their captive non-releasable parents (that can’t survive in the wild) at 6 to 8 weeks age and placed in a hack cage overlooking typical bald eagle habitat, where they have 4 to sometimes 7 weeks to imprint on eagle habitat. Eight weeks of age is the preferred transfer age, but they may be moved at 6 weeks of age in situations where they might see humans by peering over the nests after about 6 weeks age and see too much nearby human activity. This minimizes the chances for the eagles to become too tame near humans. They then have a better chance of survival in the wild if they can learn to be independent and hunt for themselves, rather than seeking out humans for food . They are never able to see humans providing food for them in their hack cages. When there two or three eaglets in an 8x8x8-foot cage, they soon learn to cooperate with each other by only one eaglet flapping their wings at a time. This is especially stimulated after about the 9th or 10th week of age when they can face a good gentle wind that they can face and gradually learn to fly in place. This strengthens their wings in preparation for flying. They can then land on the sticks on the side of their 5-foot diameter nest, thus partly experiencing the landing process on branches. When they are old enough to fly, the front of their cage is raised from by rope and pulley from out of sight of the eaglets. They can then leave the hack cage at their own leisure, without pressure from anyone, and hop onto the perch poles extending perpendicularly from the front of the hack cages. They sometimes leave the cage immediately and sometimes take a few hours to gain the courage to take their first flight to a more distant tree. As with most fledgling eagles, they might land somewhat awkwardly when adjusting their flight speed to their landing on a limb. All hacked and released eagles are equipped with radio telemetry, leg bands and wing markers to keep track of them in the wild. The radio telemetry probably increases survival of first year eagles from 50 to 55 %, by enabling the eagle workers to locate and rescue them, should these inexperienced birds get into early trouble and need to be rescued from a thick brier patch, etc. This hacking technique has been very successful in restoration of bald eagles, peregrine falcons, and other species since the 1970’s. Since DDT was banned from use in the US in 1972, hacking has substantially accelerated the recovery of bald eagles from only 417 nesting pairs in the lower 48 states in 1963 to well over 12,000 in 2011.

      • Robin says:

        Thanks Bob for your answer, but I’m still not sure that it’s wise to take the young eagles away from the parents at that early of an age…it has to be beneficial to both the parents & the young to stay together as a family, & I like the thought that baby eagles learn life skills from watching what their parents do right in & around the nest, & that opportunity has been taken away from these babies…& after all, these babies haven’t been abandoned, the parents are living. If humans are able to peer over the nests & there may be too much human activity nearby, I’d say that needs to be fixed to accommodate the eagles being in a more natural setting, instead of favoring the nearby human scenerio. I guess we’ll just have to agree to disagree & leave it at that.

      • Bob Hatcher says:

        Robin, Any eagle held in continuous captivity must be non-releasable, or else they are required by federal and state regulations to be released.. They are non-releasable due to prior injury, or they may never have learned to hunt for themselves in the wild. By definition, any non-releasable eagle would die if released into the wild. They therefore would not be good examples for their released young to learn to survive. However, non-releasable eagles are put to good use as captive breeders and/or for public education. Their young must be released if capable of survival. There is no problem of the public peering over the edges of nests when the eaglets get over 6 weeks age. At that age, the EAGLETS are generally large enough to peer over the edge of the nest. If close enough to an abundance of people, such as in a theme park, they may risk becoming too humanized if exposed excessively to humans. That human scenario problem is avoided if the eaglets are moved to a hack site where the eaglets can become imprinted on natural eagle habitat. We therefore agree that eagles are best accommodated in a more natural setting as soon as they are old enough to adapt to it and improve their chances of survival. Thanks for asking questions that I hope have been clarified.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s