Snow, snow, go away! But as awful as the weather looks, our eagles are ready for it. At Decorah North, DNF incubates her eggs through a snowstorm. Her tightly-lapped feathers act like shingles, keeping her (and her eggs!) protected from ice, snow, and cold drizzle. Their oh-so-carefully constructed egg cup – think of all the materials that Mr. North and DNF brought in, and all the work they did to mold, conform, and tweak them! – traps heat from their brood patches and keeps their eggs warm, well-cushioned, and alive. In Decorah, Mom and DM2 get their groove on! Will they lay eggs at N2B after all? Please join us on the Confusion Couch for another episode of ‘As the Nest Turns’ and remember: whatever happens, we’re all good in the oaks and cottonwoods.
Thank you so much to our camera operators for capturing such great moments, to our video makers for sharing them, and to you for watching, learning, and especially for caring!
Decorah Eagles North
February 21, 2021: DNF protects her eggs.
February 21, 2021: DNF blanketed in snow – https://youtu.be/ImlVtP5_1Ng. DNF keeps her eggs warm and dry through a snow storm. At 6:36, she stands up and and shakes the snow blanket off, rolling her eggs and impressing us with her dedication and ability. The snow is at least three inches deep, but her eggs are warm and dry! At 8:03, we get an impressive PS before she settles back over her eggs.
February 21, 201: Decorah North Eggs closeups – https://youtu.be/2oXhmfp210Y. DNF and Mr. North have been keeping a tight lid on the eggs, but we get a few nice looks at them in this video, along with some lovely close-ups of DNF and Mr. North.
What’s in those eagle eggs? DNF laid her first egg on February 16, and her second on February 19. Here’s a peek inside a bald eagle’s egg at four days old. The tiny embryo somewhat resembles a tadpole! Egg one has a heartbeat: egg two does not yet have a heart. https://www.raptorresource.org/2020/03/05/peek-inside-a-bald-eagle-egg-4-days/
February 21, 2021: Northern Harrier – https://youtu.be/LXCv_9DnuzY. Northern Harriers are tall grass hunters. Like owls, but unusual for diurnal birds of prey, harriers have facial discs! A harrier’s body shape is also super-cool: it combines the long tail of an accipiter with wings somewhere in between a buteo and an accipter, and it can fly dihedrally like a turkey vulture as it quarters over a field. You can learn more about northern harriers here: https://www.allaboutbirds.org/guide/Northern_Harrier/id and compare BOP body plans here: https://www.raptorresource.org/2019/06/28/identifying-birds-of-prey-in-flight/.
February 21, 2021: Mom gets serious about eggs
February 21, 2021: Mom Shows Dominance Over DM2 – https://youtu.be/3NdusuS_RoE. The video opens with DM2 on N2B. Mom flies in at 28 seconds, DM2 starts lumberjacking a large stick around the nest, and the two have a quick beak-off. DM2 keeps trying to work, but Mom has other things on her mind! At 2:35, she makes her intentions very clear: footing DM2, vocalizing, and twisting her tail to let DM2 know she is feeling frisky!
Eagles have sexual preferences. At Decorah North, Mr. North usually gets on top. But in Decorah and SW Florida, the female frequently gets on top. Many eagle couples are monogamous till death do them part, but researchers have documented polygyny, polyandry, and eagle divorce. Some thoughts on that here: https://www.raptorresource.org/2020/03/27/musings-place-stories-and-eagle-intelligence/.
February 18, 2021: Copulation on the Y branch – https://youtu.be/t-mzNsAZC4U. The video opens with Mom exploring the old N1 site (note the small clump of nesting materials that somebirdy brought into the fork of the tree). She flies over to the Y, giving us a postcard pretty look at her perched against a snowy background. But Mom and DM2 have more than the view on their minds. DM2 flies in at 4:22 and the two enjoy a little afternoon delight!
Odds and Ends
Male eagles, like most male birds, lack an external phallus. Eagle mating goes something like this. An eagle (usually but not always the male) approaches its partner, vocalizing, swishing its tail, and leaning into or looming over its object of desire. An uninterested female (not now, dear!) might respond by standing up and starting what looks like a breast-bumping competition. An amorous female tilts forward, allowing her mate to land with his curled feet lodged on her back. She twists and moves her tail feathers to one side so he can press and twist his cloacal opening around her cloaca, passing sperm from his cloaca to hers. Intense, rapid vocalizations often precede and accompany mating, which takes seven to twelve seconds. You can learn more about it here: https://www.raptorresource.org/2020/02/06/courtship-copulation-and-other-things-romantic/.
Bird-friendly glass to cover new Essential Buildings in Duluth: https://www.duluthnewstribune.com/news/science-and-nature/6894925-Bird-friendly-glass-to-cover-new-Essentia-buildings-in-Duluth. This is super cool and congrats to Laura Erickson for another success in her awesome advocacy for birds!
Mars photo-booth: https://mars.nasa.gov/mars2020/participate/photo-booth/
Good old-fashioned fun! Upload a photo of your favorite eagles (or falcons, or dogs, or whatever) and enjoy!