Fort St. Vrain Eagles and Blogs

2023 Xcel Energy Fort St. Vrain Recap

August 14, 2023: FSV47 getting ready to fledge!

– By Lisa Levesque. Thanks so much to Lisa and the Fort St. Vrain fans for their detailed observations and support! In December of 2022, Ma and Pa returned to the nest area. January brought some nestorations and quite a few migrating visitors. February really ramped up with the plans for eggs. Rails were built up high and lots of grasses brought in. The first egg was laid on March 2, 2023 at 6:14pm, the 2nd on March 5 at

From bobble heads to eaglets: Natal down, thermal down, and flight feathers!

April 25, 2023: DH2 sprawls comfortably in the nest.

As DH2 starts to sprout pinfeathers, we’re getting questions about natal down, thermal down, and juvenile feathers. Unless otherwise stated, the information in this blog applies to altricial birds, although most research in this area has been done on precocial and semi-precocial birds like ducks, geese, and cranes. Altricial and precocial birds have some marked differences in pre-hatch follicular development and post-hatch molts.   Natal down, thermal down, and juvenile feathers Does thermal down sprout from natal down pores? Do flight

Sweet Eagle Dreams!

April 14, 2023: Sweet Eaglet Dreams, DH2!

This blog on eagle sleep was first published in 2017. We’ve recorded adult eagles dreaming, but this is the first time we’ve captured it in an eaglet. In addition to what appears to be dreaming, look for preening, earholes (the dark holes behind and below DH2’s eyes) and the remnants of DH2’s egg tooth, which is already rubbing away.  Do Bald Eagles Dream? Do bald eagles dream? Some footage of DH2, the seven-day-old hatchling in Decorah, got us discussing this

Bald eagle tongues and beaks!

March 25, 2024: DN17 and 18 eat.

We know that bird beaks are specialized for feeding and daily tasks. Birds of prey have strong, curved beaks with sharp edges to help them tear meat. Falcons specialize even further, adding a tomial tooth to help them kill prey. Dabbling ducks have tiny, comb-like structures on their beaks to strain small animals, insects, and plants from water and mud, while piscivorous ducks have saw-like structures to help them hold on to struggling fish. But what about bird tongues or,

Peek inside a bald eagle egg: 24 days!

Development of an avian embryo

There are two eagle eggs in Decorah trout hatchery nest N1. DH1 is about 27 days old and DH2 is about 25 days old. What do they look like? Let’s take a peek!  What do embyronic 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 this animation uses a chicken

Monday. March 13: NestFlix and News

March 8, 2023: Mr. North at the North Nest. He is an awesome, dedicated father and is doing his best to care for the egg.

Ma FSV laid her third egg at Xcel Energy’s Fort St. Vrain nest on Thursday, March 8, which brings the total number of eggs in our nests to six: three at FSV, two in Decorah, and one at Decorah North. DNF and Mr. North’s lone egg is 21 days old, HM and HD’s two eggs are 16 and 13 days old, and Ma and Pa Jrs eggs are eleven, eight, and four days old! Here’s a peek at what’s going

March 6, 2023: What are we looking forward to this week?

March 6, 2023: A Canada Goose at N2B

Another Egg for Ma FSV? As of this post, we have one egg at Decorah North (hatch estimated on or around March 28), two eggs in Decorah (hatch estimated on or around April 4), and two eggs at Fort St. Vrain (hatch estimated on or around April 10). Ma usually lays three eggs, so it’s possible she could lay again on March 9th. Are the geese going to lay eggs again? We’ve seen them checking out N2B, but HD doesn’t

First Egg for Xcel Energy’s Fort St. Vrain Eagles!

March 3, 2023: Pa FSV with his egg at Xcel Energy's Fort St. Vrain nest.

Congratulations to Ma FSV and her mate Pa Junior! Ma laid her first egg of 2023 at Xcel Energy’s Fort St. Vrain nest in Platteville, Colorado yesterday at 6:18 PM. Ma usually lays her second egg three days after her first, so we’re looking forward to another egg on March 5! The first hatchling will be FSV47: the 47th eaglet produced in this nest since we started counting in 2006. To watch the Xcel Energy Fort St. Vrain eagles, follow

How long does it take a bald eagle to lay an egg?

An egg in cross section, modified from Romanoff and Romanoff, 1949

How long does it take a bald eagle to lay an egg? We think that female bald eagles begin laying eggs five to ten days after productive mating begins. In 2018 and 2019, Mom laid her first egg about eleven days after copulation went from casual to frequent…and very determined on Mom’s part.  We’ve often seen female eagles take the lead – beak-biting and footing their mates, loudly vocalizing their intentions, and mounting them! You don’t need to be a

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