Boney Island eagle nest comparison

Local wildlife photographer Kurt Van Galder who spends quite a lot of time watching and photographing the Boney Island eagle nest has concerns about the tree the eagle nest is in. It is built in a dead cottonwood tree and you’ll see in the photos that it lost one of the big supporting branches in the past months, but thankfully the break occurred where the branch can still support the heavy nest. It looks solid enough to last through this year, but a strong storm could possibly damage the tree more. In July of 2012 winds blew down the nest with 2 eaglets that were almost ready to fledge (leave the nest). The blow down was captured by Patsy, a local resident – see the dramatic video below. A rescue mission was launched by Northern Illinois Raptor Rehab & Education volunteers on the same day. They were able to locate one female and rescue her. She was kept at their rescue for 3 weeks, then release in the same area. The other eaglet was spotted by the public, and because it was ready to fly, it survived with the help of the parents. After the release of the female, the whole family was seen together.  The adult couple rebuilt the nest in a different tree on the island the next season and have continued to add on to it. This is the cottonwood tree they have been using for the past 8 breeding seasons. 

Boney Island Eagle Nest | Photo by Kurt Van Galder

Bald Eagle Nest Facts

A bald eagle nest is the largest nest of any North American bird, and can be up to 13 feet deep, 8.2 feet wide, and up to 1 ton in weight. While not that large, the Boney Island nest on the east edge of Boney Island in the middle of the Rock River is a classic example of an eagle nest and here is why:

  • Bald eagles like to have a clear view in all directions around their nests.
  • The nest needs to be higher than the surrounding vegetation to provide both easy access and a clear view of possible threats to the nest.
  • Nest sites typically include at least one perch with a clear view of the water, where they forage.
  • The trees that are tall and strong enough to satisfy eagle nesting needs tend to be old and sometimes may be nearing the end of their life.
  • Occasionally, the nest tree dies but stays strong for a time and the eagles will continue to use their nest, despite the death of the nest tree, often until the tree or nest falls down.
  • When an eagle nest blows down, the eagle pair will usually build another nest nearby. Bald eagles are very territorial birds, and most breeding pairs return to the same nest site year after year. They may use the same nest annually for as many as 35 years.

Nest Construction Facts

  • First year nests are usually smaller, and the nest size will increase each year as eagles re-use the nest and add sticks to it.
  • Both sexes bring materials to the nest, but the female does most of the placement.
  • They weave together sticks and fill in the cracks with softer material such as grass, moss, or cornstalks.
  • They will pick up broken sticks from the ground, and sometimes break branches off trees.
  • They take as many sticks as they can find close to the nest, but may lug some branches as far as a mile, carrying them in their talons.

Bald Eagle Nest Facts source:
Read more about the Boney Island eagles

The video below was captured in July 2012 of the Boney Island eagles when the nest blew down with two eaglets in it.