Decorah Eagles and Blogs

April 12, 2025: Decorah Day Trip

April 12, 2025: Mom flying to the nest

An update on Mom and DM2. Story and photos by Robin Brumm It’s been a really long time since I’ve gone to Decorah to check on Mom and DM2! Since the weather was finally cooperating for the weekend, I decided to go on Saturday morning, so I packed up my camera and off I went. To see Mom and DM2’s nest, you have to walk down the trail quite a ways. I always bring my foldable wagon and pack my

Peek inside a bald eagle egg: 17 days!

This chicken embryo is roughly equivalent to an eaglet at about 13 days. We can see the bony plate around its eyes, long folded limbs, rudimentary feet and 'hands', feather germs, and oversized head. Next up: feathers and scales!

As of this blog post, DNF’s two eggs are 22 and 19 days old. We have a three-day-old egg in Trempealeau and four eggs ranging from 11 days old to two days old at Xcel Energy’s Fort St. Vrain nest. What do embyronic eagles look like as they develop and grow inside their eggs? Dr. Peter Sharpe from the Institute for Wildlife Studies developed a table of bald eagle embryonic development based on work done by Hamburger and Hamilton (1951). While

March 3, 2025: What are we looking forward to? News and NestFlix from all around our nests!

Mrs. and Mr. T. She's at left, he's at right.

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

Peek inside a bald eagle egg: 11 days!

Seven day old chicken embryo. It's roughly equivalent to a 12-day old embryonic eagle.

What do embryonic eagles look they look like as they develop and grow inside their eggs? Dr. Peter Sharpe from the Institute for Wildlife Studies developed a table of bald eagle embryonic development based on work done by Hamburger and Hamilton (1951). While not all bald eagle eggs hatch in 35 days, the stages of development look something like this… When we last peeked inside the egg, our embryonic eagle had inner and outer layers, a developing circulatory system, a

Bald Eagles, Eggs and Cold Weather

The eggs are warmed and protected by their parents’ bodies and the insulation beneath and around them.

Cold weather often raises concerns among Bald Eagle watchers. Will their favorite eagles keep their eggs warm and dry in sub-zero temperatures and snow? Eagles don’t have central heating or electric blankets, but they have everything they need to incubate their eggs through the worst a Midwestern winter can throw at them: meticulously built nests that aid incubation and withstand winter’s chill, highly vascularized brood patches that transfer body heat directly to their eggs, and remarkably robust eggs.  In short:

What is a brood patch?

March 30, 2018: Mrs. North's brood patch

Daylight length, or photoperiod, strongly influences hormone production in birds. In the northern hemisphere, our story begins shortly after the winter solstice in December. As daylight length increases, a cascade of hormones causes birds’ gonads to swell in preparation for reproduction, egg-laying, and incubation. In this blog, we’ll discuss the role the brood patch plays in incubation and determining clutch size. How do bald eagles keep their eggs warm in subzero temperatures? They apply heat via a special area of

January 22, 2025: Welcome back, DNF and Mr. North and Mr. and Mrs. T!

January 22, 2025: Mr. North prepares the North nest for eggs. IN: Rustic cornhusk bedding. OUT: Squirrel-fur lined silk sheets!

It’s (practically) a tropical heatwave! While eagles are well-suited to snow and cold, they tend to respond to sub-zero temps by reducing their activity, which is exactly what we saw through this week’s polar plunge! After bringing sticks in on Saturday, the Norths ceased nestorations until about 11:00AM this morning, when DNF flew into the North nest with a talonful of grass. Mr. North quickly joined her and the two spread nesting material, dug and scraped, checked out the nest

How do Bald Eagles stay warm in cold weather?

January 23, 2023: HD sports eye-cicles on a frosty morning in Decorah. An icy fog left everything coated with frost

Each species experiences the world differently and eagles have capacities that are far different from ours. How do Bald Eagles survive an Iowa winter without adaptive clothing and central heat? After a very warm week, temperatures plummeted on Saturday! When I jumped into my car to begin our Golden Eagle Survey, it was 25 degrees. By the time I got home late Saturday night, it was 5 degrees and the temperature was dropping fast! I checked our camera operators’ logs,

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