Raptor Resource Project

04/14/2022

Diction-aerie word of the day - Cuddle Puddle: When eaglets cuddle closely together for safety or warmth.

Both Decorah North eaglets have grown in nice 'coats' of dense thermal down, but cold wet weather is still a challenge. DN16 was clearly feeling the cold on April 13: look closely and you'll see a few shivers as it huddles with sibling DN15. DN15 appeared to pull up the blankets towards the end of the video, grabbing two small beakfuls of grass and depositing them on DN16's back and head. It might be anthropomorphic, but it looked to me like DN15 was taking care of DN16 in Mom and Dad's absence. Does DN15 remember Mom covering both eaglets up on April 12? https://youtu.be/8a09pZwOgb0. #musing

04/14/2022

Eaglet Update: Decorah North

It's been a busy few days at the North nest! DN15 and DN16 turned 18 and 17 days old today. What's fueling their incredible growth rates? We've watched Mr. North and DNF stuff skunk, rabbit, duck, placenta, squirrel, trout, sucker, and many unidentified bits of meat into hungry eaglet mouths. The eaglets' footpads and talons have grown and changed color, their grey thermal down is rapidly overtaking their fluffy white natal down, and the two of them are lunging at and gulping large strips of flesh. Of course, all that food resulted in a whole lot of eaglet poop. Little slices went to big spatters on the crib rails as the eaglets got better at sitting up, bending over, and shooting poop out of the nest - and on DNF!

I loved all of these videos, but I was particularly fascinated by DNF's extensive nest prep on April 12 (she buried the eaglets under a large grass pile), napping on the rails in the sunshine, and the foot comparison and tiny crop drop on April 9. Thanks so much to our camera operators for finding such special moments, to our video makers for sharing them, and to all of you for watching, learning, and especially for caring. We hope you enjoy tonight's NestFlix!

Decorah North Eagles

April 12, 2022: It was a busy day for nestorations!
DNF versus the corn stalks: https://youtu.be/Mnha79SCkD0. DNF is surrounded by a beautiful but troublesome golden circle of cornstalks. Decorah-ating is difficult as she struggles to get the husks where she wants them while avoiding her sleeping eaglets. At 2:47, she bonks DN16 with nest material and at 3:14, she nearly covers DN15 as she moves the husks to the right side of the nest. Windbreak? Decorah-ation? Long-term project? Only the eagles know for sure...but don't miss one of the DDD's taking a nap on a squirrel fur pillow at the very end of the video!
DNF pulling out grass and delivering it to the nest -
https://youtu.be/nNslxYXNn1M. Watch the first part of this video to see how an eagle gets grass out of the ground and to the nest! I loved how she built her stash. Instead of taking a little bit of grass to the nest, she gathered a large pile and brought it all in at once.
Another grass delivery, DNF working hard - https://youtu.be/jLUBhrcmU_k. By weight, we might have had more grass deliveries than food today! DNF brings an enormous pile of grass into the nest and proceeds to bury both eaglets: https://youtu.be/8a09pZwOgb0. That will keep them warm and dry!

Why did DNF spend so much time bringing and arranging materials today? While eagles can't predict long-term weather, they can sense the short term barometric pressure changes that accompany large storms. She was probably preparing to ride out the storms that hit northeastern Iowa a few hours later.

April 11, 2022: Napping on the rails in the sunshine - https://youtu.be/y46hoXV7Fng. When will the eaglets begin nestploration? I feel like we've been asking (and sometimes complaining) about the lack of eaglet explorers since about April 4th! Well, we finally got our wish! The warm sun brought DN15 and DN16 out to the rails, where they basked, panted, sprawled, and had us wishing they would get back to the middle of the nest bowl. I enjoyed this whole video, but I especially loved the eagle tongue close-ups at its beginning!

April 9, 2022: DN15 casts its first pellet - https://youtu.be/TIfccfrSddo. It's an eaglet milestone! Hatchlings don't have the capacity to expel non-digestible materials like scales, fur, and hair, so their parents feed them little bites of pure meat made slippery by saliva. But after DN15 gulped down a fish tail on April 7, we knew we'd be seeing a pellet soon!

April 9, 2022: Foot closeup comparison, clown feet developing - https://youtu.be/2FnIk5AVsJc. DN15 and DN16 are slumbering in the warm sunlight under the watchful eye of DNF. At 30 seconds, we get a great closeup of DN15's long carrot toes and taupe talons. At 54 seconds, we see DN16's smaller toes and clear talons. And at 1:12 we get a wonderful look at the two of them side by side. DN16 is just 34 hours younger than DN15, but its toes are pinker and its talons are smaller, shorter, and clearer. Enjoy DN16's tiny little toes now: our littlest eaglet will be sprouting clown clompers in a matter of days!

April 9, 2022: DN15 & DN16 a pile of cuteness - https://youtu.be/DX86Jsx-wL0. April 9 was a fabulous day for video! I loved this look at DN15 and DN16 in the afternoon sunshine - the thermal down tracts, DN15's growing clown clompers, and their little white heads bobbing over flannel grey pajamas! But I also loved DN15's tiny little crop drop at 4:37. Look closely and you'll see DN15's crop drop as it shifts food down into its stomach. Having a meal on tap keeps eaglets supplied with the nutrients and calories they need to sustain their growth.

04/13/2022

Photos from Raptor Resource Project's post

04/13/2022

4-9-22 Day Trip to Decorah
Story and photos by Robin Brumm

I decided to make a trip to Decorah on Saturday, since the weather was going to be nice. I don’t have to get up at dark o’clock since they are incubating and there is usually someone there all the time. So I left at light o’clock and headed across the river. You know when you see 18-20 eagles while driving over the Mississippi River, that it will be a good day!
When I got to Decorah, I decided to drive through the hatchery area. I looked around for the new eagle pair that has been hanging around N1, but I didn’t see them anywhere. I guess if I want to see them, I will have to get up in the middle of the night, at dark dark o’clock! lol
I went over toward N2B to see if I could see Mother Goose. I Walked down the bike trail that goes past N2B. When you stand on the trail in front of the nest, you look up at the nest, and you can’t really see anything that is in the middle of the nest. I walked back to my car and was able to see Mother Goose’s head peeking up above the nest rails from the shoulder of the road. I was also able to see her through some branches from the bridge, but I’m pretty sure if people don’t watch the cam, they don’t even know she is there!
I got in my car and headed over to N3. I parked, grabbed my lawn chair, camera and binoculars and headed down the trail. When I got to the spot where I could see the nest, I noticed a white head in the nest. I couldn’t tell who it was so I got out my binoculars and looked at the nest. I still couldn't tell who it was, so I took a photo and zoomed in on my camera and saw that it was DM2 incubating. So I set up my lawn chair and sat down to watch. I was watching for quite a while when I saw DM2 stand up and fly off. Hmm.. where did he go?? About 2 min. Later he came back. I guess he needed to stretch his wings a little bit. About a half an hour later, he flew off again, but this time Mom flew in! I didn’t really have to look through my binoculars or zoom in to a photo to tell that it was her. She takes up more room in the nest that DM2 does! I did take a photo and zoom in on it to make sure it was her though! While I was watching, I did ask her how many eggs she had laid, but her beak was sealed, and she wouldn’t share any info! I watched quite a while longer, and then decided I should leave. I did want to mention that watching incubation is sometimes like watching paint dry, lol
I decided to go home via the Bobway eagles nest. The last time I stopped there it looked like the parent was either incubating or brooding on the nest, so I wanted to go check again to see if any bobbleheads were visible. I got there and looked through my binoculars and saw 1 bobblehead! I quickly took a bunch of pictures and hoped that I got a picture of it before it laid back down.
As I continued on my way home, I wondered how many eggs Mom and DM2 are incubating. It is assumed that Mom laid her egg on or around March 20, so that means that hatch watch will start the week of April 25th, I’m guessing mid week sometime. I’m sure I won’t be able to see little bobbleheads for a couple of weeks after that. I guess I need to get out my calendar and do some planning!

RRP appreciates Robin's generosity in sharing her photos and reminds you they are copyrighted and may not be downloaded without her express written consent.

04/12/2022

As The Nest Turns: Decorah

If you've been watching the Decorah Eaglecam, you know that a new eagle pair appears to be settling into the starter nest we built at N1. I'll be honest: a lot of us have mixed feelings about that! We hoped the nest would lure Mom and DM2 back to the hatchery, but they chose to nest in N3 again this spring. Still, their behavior this fall gave us a little bit hope that they might make a different decision in 2023. That won't happen if this new pair makes N1 or N2B their home.

Could they lay eggs yet this spring? They are clearly a bonded couple and we've seen them copulating, but they don't currently appear to be getting a nursery ready at N1 or anywhere else that we know about. We don't think it can be ruled out, but we don't think it is especially likely given the current level of nesting activity. We'll see if that changes.

A lot of you are wondering where these eagles came from. While they could have come from an established territory with a failed or collapsed nest, they might also be a new pair that established a bond on their wintering grounds! Bald eagle winter pair formation has been documented by a few researchers, although we don't think it is especially common. There are a handful of places in the Decorah area where bald eagles congregate and large congregations on the Mississippi River are just 30 or 40 miles away: no distance at all to a pair of newly bonded bald eagles looking for a peaceful place to nest. We're really excited to be watching what might be an uncommon behavior play out right in front of us!

What will Mom and DM2 think? The Decorah territory is rich in food and eagles have been documented nesting relatively close together in landscapes that will support it. Perhaps this is one of the ways that nesting pairs increase on a landscape that will support it. These eagles also might not be bonded to the territory given that they haven't been here long and haven't started working on N1, N2B, or a new nest. We'll see what they do this fall!

What do the geese think about all this? For the most part, the eagles and geese seem to be ignoring one another. But we've seen and heard a few interactions, and Mother Goose tends to wait for breaks if the eagles are nearby or active. We haven't seen any eagles land in N2B or harass Mother Goose directly.

* I was able to find references to winter pair bond formation in Harmata, A. R. (1984). Bald Eagles of the San Luis valley, Colorado: their winter ecology and spring migration, a bulletin from the Nebraska Game and Parks Commission, and Dynamics of a year-round communal roost of Bald Eagles in the Wilson Bulletin, 104(3), 1992, pp. 536-540. In the Wilson Bulletin, the author writes: "Palmer (1988) suggested that pair formation among Bald Eagles can occur before definitive feathering and may come about through the extended association of pre-breeding individuals. At least one potential breeding pair (an adult male and Basic IV female) was formed at the ENP roost during this study. The high degree of interaction I observed between subadults, e.g., pursuit flights and
talon grasping, as well as the increased level of aggression by eagles during the nesting season may facilitate mate selection." We'll be reading a lot more about this - it certainly casts an interesting light on some of the behaviors we see on our Flyway cam!

04/11/2022

Oh, poop shoot!

Oh poop shoot! As the eaglets get stronger and more coordinated, they begin to paint the nest and crib rails white with slices, splashes, and stripes of poop. But sometimes parents - DNF in this case - get in the way! DN16 does its very best to shoot poop out of the nest, but hits DNF instead.

Wonderful moments like this inevitably lead to questions like "What is bird poop?" and "What do eagle Moms and Dads think about this?". If you'd like to learn more about bird poop, follow this link: https://www.raptorresource.org/2022/04/11/oh-poop-shoot/. And while I don't speak Eaglish, DNF's response looks familiar to me - and I'm guessing to a lot of you as well! Where did I put those wet wipes?

Original video here: https://youtu.be/zE0oWSX7hWg.

04/10/2022

We have your Saturday Night North movie marathon! The Decorah North eaglets turned 14 and 13 days old today. While the wet, chilly weather put a damper on nestploration in their second week, we thrilled to several milestones, including a first fish tail (DN15), a first pellet cast (after the fish tail), emerging thermal down, and huge cropzillas on both eaglets!

Why is pellet casting a big deal? Eagle parents feed their hatchlings 'baby food' - tiny morsels of pure meat that can be easily swallowed and are completely digestible. But as eaglets get stronger, more coordinated, and more demanding, meals start to include non-digestible bits: the scales and fins on a hastily-gulped fish tail, for example. Once DN15 swallowed a fish tail, we knew that pellet casting would follow close behind!

April 9, 2022: DN15 casts its first pellet - https://youtu.be/TIfccfrSddo
April 7, 2022: DN15 swallows a fish tail - https://youtu.be/K_3UiZjj0go.

If you've followed the Decorah North Eagles for more than a year, you know that this spring has been late and cold! Fortunately, both eaglets are growing nice 'coats' of dense, wooly thermal down. Natal down feathers - the adorable fluffy feathers that eaglets hatch with - are terrible at locking in heat. But their new grey flannel pajamas trap heat and are better at repelling water, which means that we should see a lot more eaglet exploration next week!

April 8, 2022: Eaglet cuteness closeup, lots more thermal down on 15 - https://youtu.be/Sg-fQp5jtNI

Want to learn more about natal down, thermal down, and flight feathers? We have a blog for that! https://www.raptorresource.org/2019/05/01/from-bobble-heads-to-eaglets-natal-down-thermal-down-and-flight-feathers/.

Watchers sometimes worry whether eaglets are getting enough to eat, especially when older siblings bonk down younger siblings. Bald eagles have one of the fastest growth rates of North American birds, which means that a hatch difference of as little as 34 hours can mean a huge difference in size and ability. We cross our talons and trust the eagles, but we also look at their crops. Whatever we see (or don't see) for feeding, swollen crops let us know that the eaglets are getting plenty of food! Check out these cropzillas!

April 5, 2022: DN15 & DN16 climb out of the bowl to eat fish - huge crops! https://youtu.be/nu_riiYonD0

Mr. North and DNF are also changing. As their gonads begin shrinking, they decrease courtship and pair bonding behaviors. As prolactin ebbs, their metabolisms speed up, they become more physically active, and they probably become hungrier. But they still take time for a little afternoon delight!

April 5, 2022: Mr. and DNF - afternoon delight! https://youtu.be/ZZ9ms_8lq64.

Bald eagles are so fascinating! An interesting thing to me: they go through what I think of as a human reproductive lifecycle every year. We watch gonadal recrudescence, new love, babies, children, empty nesting, and gonadal senescence. For us, that's a lifetime. For them, that's a year. What's up with our eagle Moms? Their hormonal regime is changing: https://www.raptorresource.org/2019/05/09/what-is-up-with-our-eagle-moms/.

If you made it this far, thank you so much for watching, sharing, learning, and especially for caring. Let's keep working to make a difference for all of the wildlife we love.

04/07/2022

Satellite tracking: D27 and D36

Thanks for the airmail, eagles! We received two postcards this week - one from D27 in Harmony, Minnesota and another from D36 near Cedar Falls, Iowa.

Where is D27?

D27 hatched in 2017 and is turning five this year - old enough to start her own family if she decides to settle down right away. She wasn't far from N2B on March 15 and 16, which means we peeled our eyes when new eagles showed up on N1. Could one of them be her, or D24, or even D1? While either or both of these eagles could be Mom and Dad's offspring, they don't have bands or transmitters, which means they aren't any of the eagles we're tracking.

Back to D27! She spent part of March loop-de-looping between Decorah and Harmony, a distance of about 22 miles as the eagle flies. As of April 4, she was exploring the folded hills, deep valleys, bluffs, and rivers that surround Harmony. We know she's spent time here before. Will she settle down or fly back to Decorah? We're crossing our fingers, toes, and talons that we get to find out!

How about D36?

Two-year old D36 is spending time near Cedar Falls, Iowa. If you look at his interactive map, you'll see he is sticking pretty tightly to river and public land. This area is much more developed than the Driftless, which means that animals tend to travel through and live in what natural corridors are left to them. D36's map illustrates why public land - wildlife management areas, scenic and natural areas, county parks, and other set-asides - are so important to our wild neighbors. Last year, he visited southwest Minnesota in mid-March. We'll see if he starts traveling more widely now that lakes are (finally) losing their ice cover.

Even though D27 and D36 stuck pretty tightly to their winter ranges, they put quite a few miles beneath their wings! Since January 1, 2022, D36 has traveled 983 miles and D27 has traveled 690 miles. Most of their flights were pretty short, perhaps reflecting January and February's extreme cold: about 60% of D27's 315 flights were under a mile, as were about 55% of D36's 363 flights. We're looking forward to seeing what both of them do now that spring is (finally) here! Fly high, enjoy the spring weather, and don't forget to write!

A thousand thanks to Brett Mandernack and the staff of Eagle Valley for sharing their maps, data, and expertise. Visit https://www.raptorresource.org/learning-tools/eagle-map/ to explore the travels of all of the eagles we've tracked.es we've tracked.