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2018 Falcon Cam Season

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Week of April 6

Hello all!  Now we are solidly into incubation, and the corresponding ho-hum of nest cam watching. Mom incubating her eggs for hours on end isn’t very exciting, but of course she’s performing a very important job.  Without her warmth the eggs would die. My hat’s always off to all the raptor mothers of the world (human mothers, too) for their seeming determination in bringing the next generation into the world. If you remember, last year mom had five eggs. Mom’s body is considerably larger than the male’s, and one of the theories of why is because she has to produce the eggs. Her larger body also allows for more easily covering the eggs during incubation. 

I had only one question, but it was asked by several of you. How does one tell the male from the female? You can’t tell by overall plumage because the sexes are colored quite similarly. If you had the time to study their facial feather patterns, each is unique, but subtle. The best way to tell is to actually see the two together in the box. Then it becomes quite obvious how much smaller the male is than the female.

Since we still don’t know if we have the same male and female as last year, I’ll put a challenge out to all of you. If anyone sees the male and female switch incubation duties, please mark the exact time and date and send that to me. If we get the band letters/numbers/colors from your observation, I will acknowledge you on the next Ask Jeff. Good luck, and thanks for watching.

Week of March 26

HELLO EVERYONE!!!  Welcome back to Falcon Cam 2018, our 7th year of bringing you Falcon Cam. I’m quite happy to report our female is incubating four eggs now. She actually surprised us and laid her first egg significantly earlier than last season. It surprised us so much that we didn't have the camera up and running until she had her full clutch of four eggs.

She and her partner have not yet given us a good enough look at their legs to know if they are the male and female from last year. In fact, we don’t even know if they have leg bands or not. As much as we banders want to get bands on all the Peregrines in the U.S., we know it would be impossible to do so. So, there are plenty of Peregrines in the world that don’t have bands on their legs. As a refresher from years past, the reason we place bands on their legs is to gain knowledge of the individual birds and the species. For instance, because of her band, we know the female from the last three years was banded in June 2006 as a chick at a cliff nest in Pallisades State Park, Minnesota. The male from the last two seasons was banded before being released to the wild in 2004 at a power plant in north central Missouri. He was released as a youngster through a process called hacking.

Now to your questions. Several asked when will the eggs hatch. Our female laid her first egg around March 14, but unless the weather is really cold, she doesn't consistently incubate until the full clutch is laid. If she started incubating when the first egg laid, the first two chicks would have such a head start in growth that they would outcompete the smaller, younger chicks for food and the youngest would probably die. With incubation starting after the full clutch, then all the eggs will hatch within a few hours of each other. With all the chicks about the same age, then nestling competition is equalized, even with the males being smaller than the females (yes, quite opposite of mammals). Based on incubation periods, we expect to see the eggs hatch around the last week in April. 

Someone asked how Peregrines find the boxes we humans place for them. This is a good question that I don’t think I’ve ever been asked. Peregrines like to do their hunting from tall structures that give them a commanding view of especially open areas. Peregrines are the fastest creatures in our world, and able to dive after prey well in excess of 200 miles per hour. When a Peregrine perched on high sees a bird (they eat almost strictly other birds) that it thinks can’t make it to cover before the Peregrine can catch it, the falcon dives off its perch and tries to catch the bird. Since most power plants are located along large rivers or lakes and have tall stacks and other structures, Peregrines naturally like to hang out at them, as well as tall buildings within cities. Placing a Peregrine box in an area where Peregrines hang out increases odds that the box will be used. For instance, Ameren Missouri has Peregrines nesting in boxes at Labadie and Rush Island Energy Centers, with each of those being located on the Missouri and Mississippi Rivers, respectively. Before humans (and power plants and tall buildings) came on the scene, Peregrines hunted from cliffs. Peregrines still certainly nest within cliff crevices with level, gravely floors where they can make a depression, or scrape in the gravel so their eggs won’t roll around. In the boxes we provide Peregrines with pea gravel.

Finally, someone asked if nesting Peregrines in our area stay year-round. The short answer is yes they do. Our winters are mild enough that our nesters can take what cold weather we have with relative ease. However, Peregrines can be found nesting within the Arctic circle, so those Peregrines definitely migrate south for the winters. Peregrines are the migrating long-distance champions of the raptor world, with documentation (because of bands and satellite transmitters) of Peregrines nesting within the Arctic circle and wintering on Tiera del Fuego, which is the southern tip of South America!


Thanks for the questions. I’ll talk with you all next week!


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