Wednesday, February 17, 2016

First Egg of 2016 for Fort St. Vrain Eagles

Congratulations to the Fort St. Vrain bald eagles on their first egg of 2016! The egg was laid last night around 9:22pm Mountain Time. This marks the 31st egg laid since we began keeping track in 2003!

What does the Fort St. Vrain site look like? The nest (FSV-N0) is located in a cottonwood on the banks of the St. Vrain River near Platteville, CO, on property owned by Xcel Energy.  We’re not sure how old it is, but Bob Anderson and Rob MacIntyre put the first cam system up in 2003, when the nest was already well established. FSV-N0 is built primarily of cottonwood branches (the dominant tree in many river systems out west) and lined with prairie grass.

As the eagles look out of their nest, they might view the foothills of the Rocky Mountains, roughly 15 miles west of the nest, or the junction of the St. Vrain and south Platte rivers roughly 2 miles north. The land can be broadly characterized as sweeping and open – beautiful, but very different from the folded hills and forests of Decorah and Eagle Valley. Primary food sources include the river systems (fish and turtles) and a nearby prairie dog colony that was just re-established after serious flooding two years ago.

While a two-egg clutch is more common among bald eagles, the Fort St. Vrain pair has (like Decorah) tended to lay three eggs. We can expect the eagles to begin incubating immediately to prevent their eggs from freezing. However, if the weather is relatively warm, we may see them spend a surprising amount of time off the eggs. Eggs need both an appropriate temperature (around 99 degrees) and appropriate humidity, so Mom and Dad will get up and down as necessary to control them. Adult eagles have body temperatures of 104 to 105 degrees, so they have heat to spare when it comes to incubation. Eagle eggs hatch roughly 35 to 37 days after they are laid – so we are hoping for eaglets around March 19th at Fort St. Vrain!

The Fort St. Vrain nest can be watched live at Xcel Energy’s site at or on our site at Both cams can be watched at the same time here:

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