At the World Center for Birds of Prey we have bred many species of raptors in captivity. Our goal, however, is not to propagate large numbers of species or individuals, but only the kinds and numbers desired for conservation projects in which we are involved.

For example, once the Peregrine Falcon restoration and release were complete we stopped propagating Peregrines except for those few Peregrine Falcons needed to help support the Aplomado Falcon restoration program. Peregrines provide the initial natural incubation of Aplomado Falcon eggs to increasetheir hatchibility and number of that species we can raise. Since most of the falcon production is accomplished through artificial insemination, not copulation of pairs, we can generally controlwhether eggs are fertile or not. Infertile eggs can be removed after laying by a Peregrine andreplaced with fertile Aplomado Falcon eggs.

The below photographs and brief explanation help illustrate the incubation and raising of a HarpyEagle.

After a Harpy Eagle lays an egg, the egg is left with the adults for 10 to 12 days, then brought into the lab. Once in the lab each egg is weighed and coded (1). Harpy Eagle eggs weigh 140 to 160 grams when laid and 18% less when they hatch. After being weighed, the egg is "candled" to determine if it is fertile (2). Movement inside the egg begins after 13 days. Chirping can be heard after approximately 50 days and hatch occurs at 53-56 days. When the Harpy Eagles hatch, they weigh approximately 112 grams (3). Two hours later, when their down is dry, they weigh approximately 108 grams. The young eagle is taken from the hatcher to the brooder where it will stay until it is 25 to 35 days old. This eagle is 12 days old and weighs 295 grams (4).