"All I wanna do, is grow old with you.."

 The Red-tailed hawks are able to start breeding when they are three years old. While trying to appeal to a mate, the male and female will perch on the same tree to hunt. During courtship or a mate-selecting ritual, the male and female hawks will soar near each other in circles at great heights.  After a lengthy flight, mating would usually take place after.  An interesting trait of the red-tailed hawk is that they tend to be monogamous and will only fertilize one female's eggs. This means that they will stay with one mate and will only find a new mate if theirs dies.

Red-tailed hawks are known to make fairly large nests, usually 28 to 38 inches in diameter and can be up to 3 feet tall.  Both the male and female birds help to build the nest, typically in deciduous trees approximately 12 to 60 feet above the ground. The nests are built using twigs, sticks and lined with inner bark strips, evergreen sprigs and green leaves.

The Great Escape..

Around the first few weeks of spring, one to five eggs are laid. The eggs are then incubated for about 30 days and both parents help in the incubation process. The hard shell of a bird’s egg is composed of a protein skeleton mostly made up of CaCO3 and other minerals.  The egg shell is strong enough to prevent the parent bird from breaking the shell while sitting atop it.  The shell is also able to hold in moisture, allow for the exchange of gases and resist attacks from predators.  After incubation is complete, the young hawk must try to break out of the shell.  For this to happen the young hawk “grows an ‘egg tooth’ at the end of the upper mandible and develops powerful ‘hatching muscles’ on the back of its head and neck.” (Dobkin, D., Ehrlich, P. and Wheye)

As the young hawk comes to the end of development, the hawk would swallow the surrounding liquid in the egg and “pull the remaining membrane-wrapped yolk into its abdomen” (Dobkin, D., Ehrlich, P. and Wheye) The young hawk then continues to work its head and upper body into the airspace of the egg, where it can start to breathe air and peep. Then by contracting its hatching muscles, the young hawk forces the egg tooth against the shell wall, creating a small hole and uses its newly developed head and legs to move and force the egg to break to allow a nice and easy escape.  After several weeks, the egg tooth drops or wears off and the hatching muscles waste away.


To find out how Red-tailed hawks interact with other organisms, click here.
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