Mariah in the nestbox decorated with iciclesSunday, March 9, 2008
Zwolle
This handsome fellow will hopefully start a family this season in this nestbox. For the first time Electrabel will provide livestreaming so we can all enjoy it live!James River Bridge: 4 eggs!
Lizzie laid her 4th egg. And by the looks of it, there even might be a 5th one.
Derby
Nick Brown writes about yet another Peregrine-Raven dispute this morning at the Cathedral. Both peregrines make a very alert impression this afternoon, keeping watch.Read all about it here: http://derbyperegrines.blogspot.com/
Rochester
Images of Kaver in the snow. He must be thinking, wish I stayed a bit longer in sunny tropical surroundings. 
Incubation
Female of Oberhausen turning her eggsIncubation
For an egg to develop normally, it must be exposed for a considerable length of time to temperatures a few degrees below the normal 104 degrees F (40 degrees C) avian body temperature. Indeed, the ideal incubation temperature for many birds' eggs is about human body temperature, 98.6 degrees F. Almost all birds create the required temperature by sitting on the eggs and incubating them, often transferring heat via a temporarily bare area of abdominal skin called the "brood patch."
On the other hand, the embryo inside the egg is also very sensitive to high temperatures, so that in some situations eggs must be protected from the sun. Peregrines often stand over the nest and shade the eggs when temperatures rise.
Embryos are less sensitive to cold than to heat, particularly before incubation has started. Some eggs have been known to crack by freezing and still hatch successfully. Eggs cool when incubation is interrupted, but this is not usually harmful, and few birds incubate continuously. Instead egg temperature is regulated in response to changes in the temperature of the environment by varying the length of time that a parent bird sits on them or the tightness of the "sit."
Peregrines apparently sense the egg temperature with receptors in the brood patches, which helps them to regulate their attentiveness (time spent incubating) more accurately. Since the embryo itself increasingly generates heat as it develops, periods of attentiveness should generally decline as incubation progresses. Attentiveness is also influenced by the insulating properties of a particular nest.
Eggs are also turned periodically -- from about every eight minutes to once an hour.
The turning presumably helps to warm the eggs more evenly, and to prevent embryonic membranes from sticking to the shell.
Both parents incubate. But there is a large difference in time they spent doing so. Males incubated about 3o% of time, with attentive periods of 2–3 h; female attentive period is about 4 h and she incubates 70% of the time.
Both parents are needed in this incubationproces. Because the Peregrine is a bird of prey, food is not somewhere around the corner to pick up. Hunting is required. Given the fact that only 1 in 4-5 hunt attempts are succesvol in striking prey, it's rather time comsuming. The male therefor is the one who hunts. He is smaller, can move faster and is therefor more succesful in hunting than the larger female is. He has proven her during courtship that she can fully rely on him during incubation and later on when the eyas are born, she knows he can provide. That's why she has choosen him, not because of his beautiful brown eyes !
So he is the one who hunts and takes care of the groceries. It's therefore disastrous when anything happens to him during the incubation. She will not be, or hardly be able to incubate and takes care of food at the same time.
Food is not eaten in the nest, but outside. He flies by with food and she leaves the eggs. He takes over incubation, while she eats. And.... of course goes to the bathroom. Afters hours of incubation she really has to go. She can not leave her droppings close to the eggs, because of the infectionrisk. Sanitation is essential for the health of her unborn children. And so she has to sit on a full blatter until he appears.
Sussex heights: welcome
The male 2007
The female 2007
Both parents 2007 A new season
A nesting box was put 334 feet up at the top of Sussex Heights in spring 1998. Each year since then the pair has successfully raised chicks, two in 1998, four chicks were born in 1999, but unfortunately one died; details of subsequent years can be found in our archive. In 2002 the birds decamped to the West Pier meaning that we were unable to track their progress.
The pair are believed to be the first pair to breed in an urban environment in the south of England for three years running, hopefully they will continue to produce more chicks in years to come. Peregrine falcons were extinct in Sussex between 1945 and 1990.
The pair are believed to be the first pair to breed in an urban environment in the south of England for three years running, hopefully they will continue to produce more chicks in years to come. Peregrine falcons were extinct in Sussex between 1945 and 1990.
The pair has raised many chicks in the past years. Last year, 2007, the female laid her first egg on the 18th of March. She completed a clutch of 4 eggs, from which 2 hatched on the 30th of April. They other 2 did not hatch.. Both eyas where raised succesful and fledged the 15th of June.
Another breeding season is just about upon us and the nest box camera is up and running, if the birds are on a similar timescale to previous years we should see eggs start to appear around the middle of this month.
I wish both peregrines a prosper season, with beautiful and most of all healthy chicks.
Indianapolis
Some of you may have noticed some falcon activity going on in the nestbox lately and wondering what the heck those birds are doing in there. Just poking in corners or doing a crazy, whirling dance?
Well, they are "building" their nest. But in the case of falcons, it isn't a traditional nest, like the one a robin in your backyard might build. If you look at the material at the bottom of the nestbox, you will see it consists of pebbles. And what you see the birds doing is making a depression in the pebbles. This depression area is called a scrape and will be the sweet spot for KathyQ to lay her eggs.
Both birds will get in the box and do this digging act. As a human being, I sort of imagine it would be like lying on my stomach in a pile of sand and kind of skooching back and forth with my chest while my legs and feet are pushing the sand out until a depression forms beneath me. Now, this is just my imagination working a picture in my head (I'm not responsible for any human trying to skooch a scrape). Richard likes to describe it like one of us making a snow angel, only in reverse (unless you create your snow angel on your stomach!).
KathyQ and Kinney use the breast area of their bodies and their feet also to create their scrape. There will be multiple scrapes in the box. That's why you may see one falcon over in the back corner of the box, while one works on a scrape closer to the front of the box.
Although it seems an unusual type of nest to us, it works for peregrine falcons and has for hundreds of years.
As Richard has observed through these many years (he used to watch the birds through a closed circuit monitor in Market Tower long before the world had access to the falconcam), Kinney usually has a different idea than his mate of the perfect location of where the scrape should be. KathyQ will ultimately be the decisionator and may "tidy up" Kinney's attempts at a scrape. And she will probably have a couple of scrapes in the box before deciding which one to lay her eggs in. That's exactly what John Castrale, the DNR biologist, found when he went up to check the nestbox back in February - as he put it, two nice scrapes.
By Laura James-Reim
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