Raptor Cam Blog

Find posts by keyword
Find posts by date


Red-tails lay first eggs right on schedule

by Bob Sallinger


Posted on March 11, 2009 at 9:51 AM

Updated Wednesday, Nov 4 at 2:39 PM

The Raptor Cam Red-tails laid their first egg on Friday March 6th.
They have been building their nest for several weeks and laying was expected at anytime.

In 2007, they laid their first egg around March 16th and in 2008 they laid their first egg on March 8th.

This year, the hawks are again nesting on the top level of the fire escape (same as 2007) after dropping down a level during 2008.

We are very excited about the return to the top level because it will allow for a better vantage point for Raptor Cam viewers.

Photos: Eggs in nest, March 10

Red-tails typically lay from 1-4 eggs. Eggs are laid approximately 24-48 hours apart meaning that in a large clutch there can be as much as six days age difference between the youngest and oldest nestlings.

However, red-tails sometimes do not begin incubation until they lay their entire clutch.
The eggs will not begin developing until the parents begin incubation. There is no need to be concerned if you do not see the parents incubating over the next couple of days---it just means that they are waiting until more eggs are laid.

Once incubation begins however, the parents will need to attend to them until they hatch. If wait until all the eggs are in the nest to begin incubating, the young will all appear to be the same age, but they begin incubating each egg as it is laid, age differences will be more apparent.

Incubation lasts 28-32 days. The female does the majority of the incubating with the male providing food. After hatching the young spend on average 44-46 days in the nest before attempting their first flights.

In 2007 the red-tails hatched two eggs both of which fledged successfully. In 2008 the red-tails hatched three eggs, of which two survived through fledging, but a third died in the nest due to developmental problems attributed to beak deformities and a protozoan infection known as trichomoniasis.

Thanks for tuning back into Raptor Cam. I will update this blog throughout the season with new information and natural history facts as the red-tails go through their nesting cycle.

Thanks again this year to Via Language and Beardsley Building Development for once again hosting the hawks and Raptor Cam!