1:23 PM on Saturday, March 22.
The camera operator gave us a wonderful peek at the eggs when Mr. North left this morning. The hatching window is larger, and we can see the outer shell, the inner membrane, and the eaglet moving around inside the egg. I'm not sure whether this is DN19 or DN20: we saw the first pip at 12:03 PM and the second one at 1:18 pm, which means these two eaglets will probably hatch very close together! It wasn't especially warm when DNF laid her first egg and she laid the eggs roughly three days apart, so how did she delay development of the first egg?
While we usually associate incubation with warming eggs - especially in an Iowa February! - birds can also cool them. Bald eagles regulate egg temperature by adjusting blood flow to their brood patch, shading or standing over their eggs instead of sitting on them, and repositioning the eggs and themselves to apply or decrease heat as needed. Even in a cold Iowa winter, a skilled, experienced bird can delay early embryonic development without harming her eggs. We'll have to look through our data and see whether more experienced parents are likely to have eaglets that hatch closer together.
If you missed our blog on hatch, learn more about the process here! https://www.raptorresource.org/2025/03/18/announcing-hatch-watch-at-decorah-north/
#baldeagles #hatching
Through Rain and Snow and Dark of Night
In 2016, Mr. North was a new father: uncertain, determined, and guided by instinct. Mrs. North, patient and steady, showed him the way.
In 2019, DNF became a mother for the first time. She, too, drew on instinct, learning the rhythms of parenthood with Mr. North at her side.
Seasons and storms have come and gone, shaping them into the experienced, unshakable parents they are today. Through snow and rain and heat and gloom of night, they shelter their eggs and hatchlings beneath them: undaunted, unwavering, together.
https://archiveofourown.org/works/14364087
Bald Eagle DNF listens to her eggs
The delivery room floor pacing has started, but we haven't seen an external pip yet! Notice DNF's unwavering attention to her eggs: I can't hear chirping or vocalization, but she sure seems to be listening to them.
What was going on with the geese this morning? A raccoon tried to get into the nest while both of them were there! This went a little better for the raccoon who investigated the eggs last week, before MG started full incubation: https://youtu.be/4QnHay1ajUo?si=QArQZVmF14IVnUiV and https://youtu.be/M9UbphJOjic?si=JNFzPJumJ-eVOwI1. But geese are large, formidable foes and the raccoon quickly backed down.
How large are Canada Geese? Cornell tells us that they are 29.9-43.3 inches long (76-110 cm), weigh 6.5 to 20 pounds (I'm assuming the large geese are subspecies maxima), and have a wingspan of 50.0-66.9 inches (127-170 cm).
I'm not sure what the raccoon was chewing - some equipment, perhaps? - but MG still has five eggs, so we know it wasn't one of them!
Mrs. T reacts to a mouse in the house!
Mrs. T responded to a mouse in the house with an impressive wing whap! The merry maid was foraging for leftovers this morning when Mrs. T reacted to - from her perspective - an unknown threat. She snapped her wings wide and the mouse quickly dove into the nest's understory, escaping her wrath. Startled wide awake, she remained incredibly still for a minute or two before relaxing. Not long afterwards, she joined Mr. T on a limb and the two vocalized before he flew in for his morning shift.
Bald Eagles don't hunt mice, but they will eat them, especially if the mice are foolish enough to approach following a warning. However, the danger posed by eagles is relatively minimal compared to threats like owls, coyotes, and cats, all of whom prey on mice. The nest provides food and a relatively safe haven...as long as you respect its owners! Curious about what Bald Eagles eat? Take a look at what's on the menu (hint - it involves a lot of fish): https://www.raptorresource.org/tag/menu/
Are mice a threat to Bald Eagle eggs? No. They might be able to damage very small eggs, but their mouths don't have a wide enough gape to get leverage on an egg the size of an eagle's. Hatch watch at Trempealeau starts on Tuesday, April 9: https://www.raptorresource.org/trempealeau-eagles/
Congratulations to Mr. and Mrs. T on egg #3, which arrived at 4:14 PM CDT today! This latest egg has me thinking about the possibility of a new female. While eagles are always full of surprises (looking at you and your four eggs, Ma FSV!), the shift to later egg-laying - along with the addition of a third egg this year after having just two at Trempealeau last season - really makes me wonder. I'm looking forward to hatch!
Full video here: https://youtu.be/aus3rSVJZME?si=aBLGodsH3eKq59GH
Intense Moment at the North Bald Eagle Nest
We witnessed an intense 18 minutes at the North Nest last night when a subadult eagle dropped in for a dusk-time snack. DNF was not pleased, but rather than risk a struggle that could endanger her eggs, she mantled over them and vocalized sharply, making it clear that the intruder was unwelcome.
At first the subadult focused on nestovers, paying little attention to DNF. But when it moved toward her - roughly two minutes into this video or about 16 minutes after arriving - her peal calls grew louder and more frantic. She lunged and snapped at the intruder, spreading her wings wide and forcing it back. Moments later, at 3:24, Mr. North flew in hot and swiftly chased the intruder away.
With the danger gone and her eggs secure beneath her, DNF let out a few soft vocalizations and peals before settling back down. We were glad to see her and her eggs safe and sound.
Full video here: https://youtu.be/EPmfbHujU5E?si=cQbiQeXkOjiGOhCA
Zazu Zazu! Peregrine Falcon Zazu perched at Great Spirit Bluff
Who's that bird? It's Zazu 18/U at Great Spirit Bluff! So far, we've seen Zazu, Elaine U/09, H/34 Kandiyohi, and Newman, who finally returned! What took you so long, Newman? The Falcon Bachelor started before you showed up!
We've had some questions about bird bands, so let's dive in! Why do Zazu (a male from Bay State Milling in Winona, MN) and Elaine (a female from South Bend, IN) both have a 'U' on their bands? The short answer: the auxiliary bands we use don’t indicate a bird’s sex or natal region, but are doled out based on need.
The Midwest Peregrine Society maintains a banding database and orders auxiliary bands for everyone banding Peregrine Falcons in the Midwest. Each color run - black/blue, black/red, black/green - includes a lot of bands. They generally use one-character (A-Z), two-number (00-99) combinations where either numbers or letters can come first. For example, Y/99 and 99/Y are both valid combinations in a color run.
I don't know how many combinations there are in a run because some look-alike letters might be avoided, letters can be presented in different ways, and we have some two number/two letter combinations in the black/blue run (00/AB, for example). That said, there are currently 2,927 black/blue bands recorded in the database and that is not all of the bands in this color run, so whatever the number is, it is high.
Every year, we inventory our bands and I order whatever I think we need from Midwest Peregrine. Every other peregrine bander in our region does the same. So if I need 75 bands, I get a contiguous string - maybe U/00 through U/75, for example. Brad from Indiana might need 45 bands, so he gets U/76 through V/21. Jackie from Midwest Peregrine needs 75 bands, so she gets V/22 through V/79. Greg from Wisconsin Peregrine needs 75 bands, so he gets V/80 through W/55. And so on. Birds banded in Minnesota, Iowa, and Indiana that year will have bands that start with U or V. Birds banded in Wisconsin that year will have bands th
Bald Eagles Mr. and Mrs. T
What are we looking forward to this week? Mrs. T still hasn't laid her first egg yet, which is making me wonder whether we have a new Mr. or Mrs. T! I would be surprised if she didn't lay this week, especially given the amount of time she's spent loafing around the nest recently. Go Mr. and Mrs. T! https://www.raptorresource.org/trempealeau-eagles/
The Mississippi Flyway and Castle Rock eyrie cams are both back online. Watch for falcons at Castle Rock - and the rest of our sites! - and migrants on the Mississippi Flyway. The spring tide of birds is beginning to flow up the Mississippi Flyway, which means we're seeing Bald Eagles, American White Pelicans, and Bufflehead Ducks. Enjoy the last of winter's coyotes while you can, since they won't be able to cross the ice much longer!
https://www.raptorresource.org/birdcams/flyway-cam/
https://www.raptorresource.org/peregrine-falcons/
Looking to catch up on our birds? We've got videos and news from Decorah North, Trempealeau, Xcel Energy Fort St. Vrain, the Mississippi Flyway and Decorah. Put your feet up and get ready to enjoy some NestFlix!
Decorah North Nest
March 1, 2025: 4pm shift change, good look at the eggs - https://youtu.be/oVauKu70G2E?si=DuA3C5LiS0EDMYzd. Mr. North carefully gets up and steps out of the nest bowl before flying off, leaving us with a wonderful view of the eggs. DNF flies in at 2:17 and tucks the eggs under her, shimmying from side to side to get them placed just right. The nest looks soft and beautiful in the warm golden light.
Note that DNF is facing west toward the general prevailing direction of the wind. She and Mr. North have built a nice berm to protect them, and her streamlined figure is less likely to be suddenly rocked or flipped up by the wind. While she and Mr. North are incubation professionals, even new parents build nests that minimize wind and maximize warmth. The nest looks so cozy that I wouldn't mind taking a nap in it!
February 28, 2025: 3 male Ring-necked Pheasant f
Bald Eagle Mr North brings a gift
♫ Corn ♩♪♫♬ husks on ♫ my ♪ shoulders makes me ♫ happy...
Mr. North brought in a lovely corn husk bouquet for DNF this morning! After draping his gift over her broad shoulders, he moved it to the west side of the nest: a handy door snake to keep out drafts on a cold and very windy day. Today, it will cushion her feathers and help keep wind from sneaking through the rear door. Tomorrow, it might be shredded for additional insulation or pushed off to the side if the weather warms. Fine-tuning nesting materials - an eagle obsession! - is one way they respond to late winter's ever-changing weather.
DNF's eggs are turning 17 and 14 days old today. We're waiting for a third egg at Xcel Energy's Fort St. Vrain plant and a first egg at Trempealeau.
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