The 2023 season was a tough one for the North Nest. While Mr. North and DNF started well, we documented at least five adult and subadult intruders between February 20th and March 20th. They followed Mr. North to the nest, perched in nearby trees, flew by the nest, attempted to steal food, and generally disturbed nesting activities. On February 23 – the day that DNF would normally have laid her second egg – she spent much of the day chasing intruders away. Prior to that, her incubatory behavior was relatively normal. After that, she stopped incubating her lone egg.
Nest guarding and intraspecific intrusions: https://www.raptorresource.org/2023/03/16/nest-guarding-and-intraspecific-intrusions/
Thanks to camera operators and a boots-on-the-ground visit by Dave Kester, we know that there were multiple intruders, we know that there were simultaneous intrusions, we know that some of the intruders were adults, and we believe that at a few of them were adult females. Had the intruders moved on quickly, been a less threatening combination of age and sex, or stayed away from the nest, things might have gone differently. But we believe that her response to the constant presence of adult female intruders interfered with her ability to lay eggs and produce prolactin, aka the incubation hormone. While Mr. North underwent incubation-related hormonal change, DNF guarded her nest, mate, and egg. Instead of producing prolactin, her body was producing hormones linked to aggression, territoriality, and stress.
If a single bald eagle could incubate eggs to hatch, Mr. North would have done it. He faithfully sat over the couple’s lone egg, incubating day and night while she kept invaders away. Unfortunately, a snowstorm drove him from the nest on the night of March 16th and the egg sat for hours in the snow. It broke on March 21, most likely because of freezing, and the Norths did not reclutch.
Will the Norths attempt to nest again in 2024?
DNF and Mr. North were seen on or near the nest several times since the beginning of August, which gives us hope that they will. In the meantime, our camera operators are counting crows (and many other birds and animals!). This year, GABear has documented 62 species of birds in 32 families, 17 species of mammals (including cows!), and two turtles. There is almost always something to see at the North nest even when Mr. North and DNF are out of sight!
Videos
The North nest camera will be shutting down on August 16th, but swing by our website: https://www.raptorresource.org/birdcams/decorah-north-nest/ or Explore’s North snapshot page: https://explore.org/snapshots/decorah-eagles-north-nest/ to see the North eagles and their many neighbors. To scroll through videos of the North nest, visit our 2023 North Nest playlist at https://www.youtube.com/playlist?list=PLeNR2ocnlCOckyZbmPR4EkqaexiNxyTmw.
The North Nest and Decorah Eagles cams will return on October 14th.
The Raptor Resource Project