Scottish Eagle Centre
Eagle breeding at the Scottish Eagle Centre
The Scottish Eagle Centre is the largest facility in the world concentrating on breeding eagles. It has also bred the most species of eagles than any other organisation.
All our young birds are parent or foster parent reared, no young birds are imprinted unless specifically for a valid reason.
Some young birds are available each year please contact us for enquiries or details.
Growth rate in eaglets
A trio of African fish eaglets at around 7 days old (fig 1)
Eagles, as with all raptors have an intense growth rate, taking a standard large eagle such as a golden eagle, from the data given in this paper. Data can be comparable to small eagles (Bonelli’s, African hawk, booted) or extra-large eagles such as the Steller’s sea eagle.
Large eagles will hatch at approximately 100gms and grow to around 6kgs (female) all in 16 weeks. With this phenomenal growth rate there are many scenarios that can interfere with a perfect growth curve.
There are several areas that can affect the growth of an eaglet, parenting, ambient temperatures / weather conditions, food supply / quality, or brood size. In the wild any one of these can cause nest failure, deformity or death of an eaglet.
Here we are focusing on raising eaglets in captivity (though many of these issues are equally relevant to a wild raised eaglet), the 2 main issues are temperature control and food supply / quality.
Parent rearing is best. It may seem pretty obvious that a newly hatched eaglet has to be kept warm, but eagles are prone to overheating, too much heat will kill an eaglet. We are not going to give precise time frames and temperatures for each eagle species or scenarios, use common sense and monitor accurately the eaglets. An eagle hatches at 37.2c and will be off heat by the time it is 21 days old (ambient temperatures dependent), any heat source must be adjustable, an eaglet must be able to move away from any heat source, so beware any brooder that does not allow this.
(fig 2)
Feeding
Parent rearing is best. Good quality, whole carcass feed is a necessity, unless this is supplied growth deformities can take place, sometimes these deformities are not visible but they will compromise the eagle later in life.
Moistened meat only is adequate for up to 3 days after hatching, bone and casting should be introduced in varying degrees from then on, without the latter deformities will occur.
There are 3 phases of growth in eaglets the ‘Growth Chart’ (fig2) shows this, time frames will overlap with different species.
Phase1, mainly skeletal and body growth, keeping warm with regular feeding.
Phase 2, continuing to grow physically with massive skeletal growth and now feather growth is starting to take place. This phase is where lots can go wrong, in the early part incorrect feeding can cause skeletal damage or retarded growth. In the latter period when feathers are taking the majority of goodness out of the blood supply ‘Angel wing’ or trace lines can cause major deformities or feather damage. This can result in death or severe long-term issues.
Phase 3 is where skeletal growth is almost completed, feathers will almost have stopped growing, though not have hardened off. The eaglet will have fledged or be close to doing so. But this is just as important a phase as the other 2, the eaglet will look grown but will have a very poor body condition, it needs now to bulk up its weight adding a kilo or more of weight through muscle conditioning and body mass. This will continue for as long as 6 months from hatch.
In a wild bird this all needs to be done before the bird is 16 – 20 weeks old and the onset of Winter makes good food sources unavailable.
3 week old Steller’s sea eagle (fig 3)
All bird species have a predisposition for rapid growth and the ability for muscle growth and fitness to reach its maximum under the correct rearing conditions.
Note the species that breed in the UK and migrate almost as soon as they fledge, swallows passerines to Africa, wildfowl breeding in the Arctic Circle migrating to the UK for Winter.
Eagles muscle tone and fitness is no different, as an apex predator they need the maximum of fitness and muscle tone to survive. Eagles will fledge before feathers have finished growing and body mass is completed, this gives them time to start the fitness programme while still being supplied food by the parents.
Although muscle tone and fitness is not as crucial in a captive eagle, it is a well-known fact within the falconry community that to capitalise on this predisposed window. It will considerably aid the flying and successful hunting of a bird of prey in its first season.
A female (left) and male, 12 week old golden eaglets (fig 4)
Warning, do not hand raise any eagle or raptor unless you have experience in raptor propagation.