This photo shows two views of the perches. In general, avian electrocution happens when a bird makes a connection between ground and a live wire. Energy flows through the bird's body to ground. The perches built by Mr. Condon's class in Decorah are located above the power lines and Alliant added an insulative sleeve where the live wire passes under the perch. The sleeve is long enough that even a stretching eagle should not be able to connect with the wire.
We'd like to thank everyone involved for their work protecting the Decorah eagles, especially the D12 Memorial Group, Raptor Nation, Mr. Condon and his class, Decorah Building Supply, Alliant Energy, and Puget Sound Energy.
A few links:
Students building perches: http://youtu.be/7VPqY9LM3EE
(this video also does a good job of explaining electrocution and perch safety)
The D12 Memorial Group's story: http://raptorresource.blogspot.com/2012/11/bird-safe-power-poles.html
Perch blueprint: http://www.flickr.com/photos/68092929@N03/8203641600/
