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April 11, 2014
From Jeff:
Hello, everyone!     
What about life expectancy of peregrine falcons in the wild?

Because of the bands on their legs, and having the peregrine falcon cam, we know the exact age of both SiouxZee and Coal. As a refresher from last year, SiouxZee was hatched in 2006 at a power plant in south central Iowa, and Coal was hatched in 2004 at Ameren Missouri's Labadie Energy Center. (I got to put the bands on Coal and his siblings that year...small world.)

This puts both birds at about middle to late age. If peregrines survive their first year of life, they have a good chance of living 12 - 15 years in the wild. Knowing this, I expect SiouxZee to have 2 - 3 more years of good productivity, laying 4 or 5 eggs with all having a good chance of hatching, and then her productivity will probably decline. She may start having 3 - 4 eggs, and maybe 1 or 2 won't hatch.

Peregrines are like humans in that as their bodies age, things start to not work as well as when they were young. The same goes with Coal.

Peregrine age also effects their ability to defend their nesting territory. There are so many peregrines in the environment now, I'm sure our pair has to fend off challengers many times during a year, especially during migration times (early spring and autumn).

One day SiouxZee or Coal may suddenly disappear, and we would probably see a replacement female or male. The territory our pair possess is a good one, with the major flyway of the Mississippi River right under their beaks. This means there are a lot of prey birds moving up, down and across the river, so plenty of food for Coal, SiouxZee and their kids. If either bird falls out of the picture, it's almost a definite another will take its place and continue to nest in the box.

Earlier I mentioned "if peregrines survive their first year of life." Sixty to 80 percent of all birds hatched in any one year die before they reach one year of age. Life in the wild is extremely hard! Once a peregrine fledges (leaves the nest and eventual care of its parents), it may not be able to catch enough food to survive. As fast as peregrines are, almost 70 mph in level flight and a record 261 mph in a dive after prey, they still have predators. At a year of age, in theory, "they've seen it all," so there's a better chance of catching more than enough prey to survive, evading predators and man-made hazards.

In the meantime, SiouxZee and Coal have a great chance at being successful for the fourth year in a row, with 5 eggs in the nest due to start hatching April 29!

March 31, 2014
From Jeff:
Hello, everyone and welcome back to Ask Jeff and the Peregrine Web Cam! I am thrilled to again be able to answer your questions. Let's get started.

There were a lot of questions about the number of eggs and incubation period.

SiouxZee and Coal's first egg was laid on March 21, 4 days later than last year and 11 days later than the year before.

The lateness could be for many reasons. One of the best reasons is perhaps because of the harshness of the winter. With such a cold winter, all the way up to mid-March, all birds could put off laying for days to, in theory, give their eggs a better chance of surviving to hatchings.

About once every 2 days, SiouxZee laid an egg, and as of March 29, she laid her fifth egg. Last year she had 4 eggs and in 2012 and 2011 she had 5 eggs. From 2011 through 2013, all of the eggs hatched. We'll keep our fingers crossed that her 5 eggs this season will successfully hatch as well.

With her last egg laid, SiouxZee will now faithfully incubate her eggs, with a little help from Coal, through and including the last egg hatching. We should see the first egg hatch on April 29. 

Watch the video of Coal sitting on the eggs! Notice, he flies in and waits for SiouxZee to leave. Then he takes her place to help incubate the eggs. View video.

It takes about 30 days for a Peregrine egg to hatch. Peregrine parents don't faithfully incubate the eggs until the last egg is laid, the theory here is if mom started faithfully incubating as soon as the first egg was laid, the first 2 kids hatched would have such a head start in development that they would eventually muscle out the smaller, younger chicks and get all the food brought in by the parents.  Sporadic incubation until the whole clutch is laid helps ensure all the chicks hatch in about 2 days and all are roughly the same size with an equal chance of getting the food mom and dad provide.

Several of you asked if last year's chicks have been seen.
To my knowledge, none of last year's chicks have been spotted by anyone in the world, and I am serious when I say, "world."  In Latin Peregrine means, "wanderer," which describes how far these fastest of the world's animals migrate.  t would not be out of the question to have a band reported from the southern tip of South America, anywhere in Alaska or even the northern most tip of Greenland.
However in December 2013, we did get a band report from a chick hatched in 2012!  Someone took his picture near Lock and Dam 26, which is only about 10 miles downstream from the Ameren Missouri Sioux Energy Center.  


Photo courtesy of Randy Koratev.

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