Wednesday, September 09, 2015

Update from Decorah

Answers to your four most commonly asked questions, plus a bonus photo at the bottom of the page!

When will Mom and Dad start working on a new nest?
Did someone mention Eagle Time? In general, Mom and Dad start working on their nest sometime in October. Robin spotted Mom near N2B at one point, but I doubt we'll know whether or not they will adopt it for a month or so. For a time-lapse of the nest, check out this video, pieced together from October 2014 through January 2015: While nest work started in late October, it didn't really kick into gear until maybe mid-November.

Note added on October 10: Mom and Dad have started working on the nest. Visit our youtube channel for more:

What triggers Mom and Dad to start working on the nest? 
I've got a blog on this subject here: The short version? Two ideas: Daylight length is quite similar in mid-February and mid-October, which might encourage bonding activities in the photorefractory period that echo those in the photosensitive period, especially between territorial mates.

The eagles might be impacted by Zugunruhe (migratory restlessness, which is also influenced by daylight length). Mom and Dad don't migrate, but many eagles do. Perhaps the suite of behaviors and hormones that direct migration in some birds influences our eagles to return to nest-building.

Where are the Tree Amigos?
Given that no one has seen them, D21, D22, and D23 have most likely dispersed. D1 dispersed on August 13, 2011. D14 left twice, once on September 5th and for good on September 22, 2012. Four was a bit of an outlier. She took two longer exploratory flights in October 2014 before leaving for good on October 25. You can look at the flight maps of all three here: or explore Four's last month in Decorah here:

What's this about HD cameras?
It's true - we are moving to high definition! Cameras will be installed or replaced at N2B and N1 later this fall. Watch for announcements in early October!

Four at the Carlson Pond on 9/9/2014
Who is the eagle in this photo?
On this date in 2014, Bob took this photo of Four at the Carlson pond about a mile from the hatchery. This was one of her first 'long' flights and raised our hopes that she might disperse - which she eventually did, although she waited until late October to do so. Look for more 'on this date' photos as we wait to see what the eagles decide to do!

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