Another successful KestrelCam season has come to an end. We hope you enjoy this photographic overview of the nest at The Peregrine Fund’s World Center for Birds of Prey in Boise, Idaho.
2013 was another great Kestrel Cam season, with our box successfully fledging four chicks. The fledglings have been spotted intermittantly by various members of our staff, and we wish them well as they begin their journey of surviving in the wild.
Young American Kestrels just like these are fledging all across the continent, emerging from nest boxes that were put up by our partners. Such nest boxes can be a very educating and rewarding experience, and as such we encourage all who are able to set up nest boxes of their own. Individuals can either buy kestrel nest boxes, or try building them - We supply plans here on our site for anyone to use. It is easy to become a kestrel partner, and we hope to welcome more citizen scientists into our ranks next breeding season. For more information on setting up a nest box of your own, see the main page linked above.
At 5pm today, the cameras will be shut down for the season. A slideshow that showcases the early lives of our four kestrels will be put up in their place. We will be preparing the boxes and cameras for next year's use in the meantime.
We thank all of our viewers and supporters, and look forward to bringing back the Kestrel Cam next spring !
Now that all of the kestrel fledglings are mobile, they have dispersed to areas that are not readibly seen by the nestcams. They are now out in the world, practicing their hunting skills under the watchful eye of their parents. A few weeks from now they will likely be able to survive on their own, and will leave their parents behind to find their own favorite hunting spots.
The nest box is still now being used as a roosting place at night time, however. Both adults and fledgling kestrels may return to the box as a comfortable place to sleep, and they have been doing so over the weekend. During the day however, there is often little to see. As such, we will soon be pulling the webcams and livestream offline for the season. We are working on compiling videos of the kestrels' fledging day, so keep an eye out for that in the meantime!
June 28, 12:00 p.m.
At 11:24am, the little female kestrel fledged out of the box. She was located shortly afterwards on the ground under a pine tree, munching happily on a sparrow-like bird that had been dropped there. Two of her brothers were perched above her, and the adult male kestrel was located in a tree nearby.
While we were watching, a red-tailed hawk soared into the vicinity. In a flash the adult female kestrel was giving her alarm call and divebombing the bewildered red-tail, and it made a hasty retreat from the area. This goes to show that the adults work hard to drive potential predators away from the area, so that the kestrel fledglings can explore their world in peace.
The male fledglings already look steadier and less clumsy in the trees than they did yesterday. Their newly fledged sister will probably attempt join them up there once she is done gorging herself on the bird.
June 28, 9:00 a.m.
The office of The Peregrine Fund's Library Director, Travis Rosenberry, overlooks the area where the kestrel fledglings have been since leaving the box. He has located all three of the male fledglings this morning, and reports they are doing fine. The female chick is still in the nestbox. The fledglings are now dispersing to areas not visible from our camera's position.
At 9:33am this morning, one of the three kestrel males took his first flight out of the box. Shortly afterwards, one of his brothers followed him. Finally, the female chick pushed the last of her brothers out of the box and down the side of the building. There was a brief period where all three kestrel brothers were running around on the ground, exploring. The adult female darted above them constantly, keeping watch and feeding them. Eventually, all three managed to fly upwards into a nearby pine tree.
The female chick remains in the box, but most likely not for long! The mother kestrel will continue to feed her as well, even though she has yet to fly herself.
Once kestrel chicks are out of the box, they begin to practice flying and explore their new world. Already one of the males saw a big black stink beetle and pounced on it, only to be perturbed by the nasty taste. During this time, both adult kestrels will continue to deliver food and guard the fledglings from any potential threats. There is lots of cover for them to hide in if needed, and very little human activity, so their fledging spot is a good one to start in!
The fluffy white down has nearly been replaced entirely by adult flight feathers, and the kestrel chicks have taken a keen interest in the world outside of their box. They are now about 26 days old, which means that they are ready to try their first flight at any moment.
They are jockeying for the nest position to look outside and flapping their wings to strengthen them. Their first flight will undoubtedly be clumsy, however, and they often end up in a tree or on the ground. Lucky for our kestrels, there are very few human hazards on the ground around the nest box, and young birds are quick to climb back up to a safe perch.
While some kestrels may climb back to the box after their first flight, others will spend all of their waking hours exploring outside. As with all birds of prey, the kestrel parents will continue to feed and watch over the chicks until they are able to take care of themselves.
Keep an eye out – who knows when their very first flight will happen!
Watch the video of yesterday's banding here.
The banding was successful, and all the chicks – one female and three males – were healthy and alert! The silver band on their right leg has an individual number on it, however the number will be hard to see on the webcam. The nestlings may peck at the band a bit at first, but after a while they will hardly notice it. We will post a video of the banding as soon as we can.
Now that the body feathers and flight feathers are growing in, viewers can distinguish the female from the males. The males have slate-blue color on their wings and a single broad black-and-white stripe on their developing tails. The little female is reddish-brown with black striping all over.
From now on, the white fluff will disappear day by day to be replaced by their adult colors. Next week, they will begin to look like miniature adults!
Tomorrow, June 19, the kestrel nestlings will be about 21 days old, which is the age when they are ready to receive identification bands. In the morning, we will temporarily disable the webcams so that an experienced and licensed bander can reach the nestlings. We will film this process while the livestream is down and make the video available online shortly after.
Banding marks each chick as an individual for the remainder of its life. The bands will be silver in color, with an individual number on each. They can provide valuable data on the movement of the marked birds in the event that they are re-captured or if a band is recovered when a bird dies. Scientists all over the country set up banding stations to trap (or possibly re-trap) a variety of birds for banding, and thus banding data grows by the day.
Banding will be done as quickly and efficiently as possible to minimize disturbance to the nestlings and adults. Kestrels are fairly hardy and they will most likely settle down soon after we leave the area.
Sadly, the smallest of the kestrel chicks has died, most likely due to starvation. The chick had hatched about three days after its siblings, so it began with a disadvantage. Although adult kestrels are generally careful to feed each chick in turn, young birds of prey are still competing with their siblings for food. Hunger triggers aggression and competition among nest mates. It is generally the younger chicks that bear the brunt of that aggression, which allows older chicks to maximize their chances for survival.
To us humans, this is a hard event to watch, yet we must remember that the death of a nestling is not unusual in the wild. Chicks die for a variety of reasons, including food scarcity, inexperienced parents, or a physical problem that impairs growth. Because the other four chicks appear alert and healthy, we have no plans to disturb them by removing the dead nestling. The parents can remove it on their own if it becomes a problem.
Thank you all for your continued observations and data collection, and stay tuned to watch as the remaining nestlings continue to develop. It won’t be long before they are up and walking around inside the box, eager to stretch their wings!
The rate at which these chicks grow during the 30 days from hatching to fledging never fails to impress. They emerged from eggs that were only about 1½ inches long, yet they will be fully grown and ready to fly when it leaves the nest. By the end of June, each of these youngsters will be 8-12 inches tall and have a wingspan of 19-23 inches!
Like many birds of prey, American Kestrels exhibit “reverse sexual size dimorphism,” meaning that male kestrels are smaller than females. Because the smaller males develop faster, they often leave the nest sooner than their bigger sisters. When their tail feathers come in, you will be able to distinguish females from males by their markings – striped for females, one solid band for males.
Finally, the last egg hatched and now the adults have five little mouths to feed.
The adults will brood the chicks for a week or so, depending on the weather, until they are able to regulate their own body temperature. The chicks also can huddle together to keep warm. The adults have a “brood patch,” a bare spot on their chests that allows the chicks to be in close contact with their parents for maximum heat. As the chicks grow older, the brood patch fills in and disappears.
The yolk inside the egg, which nourished the embryos during incubation, was absorbed into the body cavity of the chicks immediately prior to hatching. Although the yolk keeps them well-nourished for a few days, the chicks’ begging instinct kicks in right away. The adults are feeding the chicks by delicately placing small bits of food in their beaks.
Two more chicks visible at the lunchtime feeding.
A second chick hatched shortly after noon!
A chick! The first chick hatched yesterday. We will soon learn whether the other four eggs are viable as well. Last year, all five eggs hatched and the chicks fledged successfully.
Hatching is exhausting work for the tiny chicks, but they have special biological tools that help them emerge from their shells. A sharp structure called an egg tooth that forms on the top of their beaks is used to pierce the inside membrane and shell, allowing oxygen to flow into the egg. This stage is called “pipping.” The chicks also develop a pipping muscle on the back of their necks that, together with the egg tooth, enables them to chip a small hole in the egg and then cut the top off the shell.
The overhead camera angle in the nest box gives viewers a good look at the beautiful markings of American Kestrels. Among the most striking are the ocelli (from Latin, “small eye”), which give the appearance of having eyes on the back of their heads. Between the ocelli is a black stripe (called a malar stripe) that resembles a beak. Scientists think the false eyes and beak fool predators into thinking they are being watched even when the kestrel is facing the opposite direction.
Kestrels also have malar stripes on the sides of their heads near their eyes. They may work for the same reason that athletes put black stripes under their eyes before a big game – to reduce glare and enhance their eyesight. Like all birds of prey, kestrels have amazing eyesight that enables them to spot a mouse or snake moving through the grass while soaring high overhead.
It has been two weeks since the female laid her first egg. She now has five and seems to be incubating them quite attentively.
If all is well, each embryo is developing quickly. Given an incubation period of about four weeks, we should expect eggs to start hatching around the end of May.
You might see the female or the male – he steps in from time to time – rotating the eggs. This practice is crucial to incubation for two reasons. Rotating ensures the eggs are warmed evenly and uiniformily. It also prevents the embryo from sticking to the egg's inner memberane, which can cause problems during hatching.
This is an exciting time for KestrelCam viewers but a tiring episode for our kestrel pair.
The female spends the majority of her day and night incubating the eggs. She laid her fourth egg yesterday. On average, kestrels lay 4-6 eggs in a nesting season; we might see 1-2 more in the next few days. She rarely leaves the box, and when she does, it is not for long. She eats the food that the male brings her, "preens" (grooms) her feathers, and returns to her eggs.
The male spends his day hunting and protecting the nest box. It is his duty to provide food for both himself and the female throughout the nesting period. Kestrels feed primarily on insects and other invertebrates, as well as small rodents and birds. When he catches something, he will often eat part of it then bring the rest back for the female. Keep an eye on the KestrelCam throughout the day, and you might see this exchange!
Welcome to the 2013 KestrelCams! We are excited to again reveal the fascinating world of nesting American Kestrels – with upgraded KestrelCams! The kestrels laid their first egg yesterday so stay tuned as the female lays three to four more over the next four to five days.
Bosch Security Systems USA is sponsoring the American Kestrel Partnership and generously donated a Bosch AutoDome 800 Series Pan-Tilt-Zoom Camera. We can now reveal kestrel activities outside the box, such as adults exchanging prey and defending their nest from trespassers, and fledglings learning to fly, hunt, and survive in their dangerous new world. We are also grateful to our partners at Cornell Lab of Ornithology's Bird Cams project for continuing to provide the KestrelCams with ad-free streaming
If you enjoy watching the KestrelCam, please support our work by making a donation or becoming a member. And don't forget to contribute as a citizen scientist by logging your observations of kestrel behavior and joining the Partnership to monitor your own kestrel box. These data are used for important research by the American Kestrel Partnership – and you can be part of it!
If you enjoy watching the Kestrel Cam, please support our work to recover threatened and endangered birds of prey. Your donation will:
Your tax-deductible donation will be used efficiently and effectively. We take pride in being a common-sense, elbow-grease, no-frills, hands-on group of dedicated professionals. We tackle only those projects for which we are the most qualified and where a definite need exists. And we always strive to leave a lasting result.
The interior camera uses infrared light to "see" in the dark and low lighting. The exterior camera also detects infrared light, hence the impression of a "lit" nestbox at night, but the light is invisible to kestrels and humans so the kestrels have a dark box for sleeping.
Females have alternating black and orange bars across their tail, back, and wing feathers, while males have blue wing feathers and only one thick black bar near the end of their tail feathers.
Check out the fantastic kestrel photos donated by our sponsoring professional photographers in our Kestrel Photo Gallery!
On average, the North American breeding population of American Kestrels has declined by an estimated 50% from 1966 to 2012 according to USGS Breeding Bird Survey data. However, population trends vary by geographic region, such as New England, where the population has declined by estimated 88%. Check out our Population Declines webpage to see the trend in your region.
Buying or building your own kestrel nesting box gives you the opportunity to enjoy the colorful and charismatic American Kestrel up close. It also allows you to contribute to two critical functions for kestrel conservation.
1) Installing kestrel boxes creates nesting habitat for this cavity-limited species (kestrels don't build nests and will not nest without a sufficient cavity!)
2) Monitoring kestrel boxes (counting eggs and nestlings during the nesting season) and entering data onto the Partnership website produces information critical for kestrel research and conservation planning.
Check out our American Kestrel illustrated life cycle!
Find technical information at The Peregrine Fund's Global Raptor Information Network!
Visit the Cornell Lab of Ornithology's All About Birds section on the American Kestrel!
Read this first! KestrelCams and nestcams: guidelines and configuration (PDF)
Ready to purchase a nestcam? Contact our sponsoring partner! Spy on a Bird LLC sells nestcams custom configured for nestboxes and gives 15% discounts to our partners!
Want to embed the KestrelCam feeds on your website? We encourage our partners to do so and the embedding codes can be accessed on Livestream's webpages:
Bringing the fascinating world of nesting American Kestrels to you with our KestrelCams is made possible by our partnership with the Cornell Lab of Ornithology and Bosch Security Systems. We thank Charles Eldermire, director of Cornell's Bird Cams, for providing the ad-free streaming service, and Willem Ryan, Steve Tangert, and Matt Thomas for the camera donations and technical expertise. We also thank Bob Anderson of the Raptor Resource Project (and founder of the famous Decorah Bald Eagle cam!) for his early encouragement and technical expertise.