Who Was That Interloper At Decorah North Nest?

Written by Sherri Elliott

We were just as puzzled as everyone else at the Stranger Danger Drama that was playing at the Decorah North Nest on Thursday night. The “intruder” landed first at 6:31pm CT and got an earful from Mrs. North who was alarmed and agitated, with piercing alerts and warning vocals. The visitor nonchalantly paid her no mind and proceeded to wander around the nest like it was the rightful owner … picking at sticks, peering into the egg cup and nosing around the egg, and inspecting the joint before taking a brief flight to the side Bouncy Branch, and then up to the Ladder Branch. All the while, Mrs. North continued to express her agitation vocally, and at times with mantle feathers on end, even going so far as to nip at the intruder a few times while she covered and protected her egg. She wasn’t the only one who was vocal! All of us let out a gasp, had few choice words for the interloper, and were sitting on the edge of our seats wondering ‘where is Mr. North’ and why isn’t he helping? It stayed for almost an hour and a half before finally taking flight from the upper Ladder Branch out of our view.

It was a relief to see Mr. North arrive at 9:33pm CT, although his entrance was met with more vocals from Mrs. North as he nibbled at her tail and then walked on it to get around her. He picked at grasses and a stick before sidling up to the missus who gave enough leeway for him to check out the egg and then he wandered down to the lower and side left rails before taking a hop-flap to the Bouncy Branch for a lookout perch. Wait, wasn’t that the same path the intruder had traveled?

Yep, it was, and after inspecting all the footage from the evening multiple times, and minute by minute we were able to confidently conclude that the 1st and 2nd visitor was indeed Mr. North. He stayed with her until about 6:07am CT on Friday morning when he took up a perch spot on the Yonder Branch. He dutifully doted on her while she dozed off between the many up’s and down’s of repositioning herself while incubating, did a little nestorating himself, rolled the egg a couple of times and perched at both the Babysitting Branch and the Ladder Branch for sentry duty.

So why was everyone so puzzled? It took time to unravel the mystery and the clues presented. Really large? Check. Smooth head? Check. Shallow brow? Check. Small head and long skinny neck? Well, eagles can morph their appearance easily, (especially when triangulating and head bobbing), and not all images viewed showed the head and neck so disproportionate to the body. While the IR light can be deceiving, we also didn’t note the few white leg feathers that Mr. North sports, but there were other identifying features observed in feathers consistent in the eagle during both visits … like a wonky right tail feather, a lighter swash on the left wing, and a pattern on the upper back. Behaviors were also consistent with the familiarity seen on multiple walkabouts that Mr. North does own the joint.

But what about Mrs. North and her reactions? Those responses are a little harder to unravel and reason. While we don’t know why she responded both times the way she did, we’re allowing for the fact that there is an increase in hormones for egg production; she was probably startled since Mr. doesn’t generally come in at night; and there were outside influences as well with a full moon, a chorus of geese, owl hoots and coyote yip yips and howls. Plus, there have been intruders in the territory for some time now, and one could have been perched nearby causing additional distress. There was an intruder on Friday about 7:10am CT, just an hour after Mr. North had left his all night sentry duty. We heard Mrs alert with vocals and Mr dashed in from the backside of the nest and both were tracking something overhead while alerting and warning. Mr. North flew up to the Ladder Branch to defend while Mrs was incubating in the nest. The intruder made two passes at lightning speed with the second one striking into Mr. North, who took a hit, but flew off unscathed and away from the nest in a chase. We never got a good enough visual on that morning intruder, but it seemed like someone could have been nest shopping as it had a stick in its talons. Perhaps it got the warning that the enormous white oak treehouse is off limits.

We don’t have all the answers, but we’ll do our best if you have questions. There are some things we’re just not certain about, including whether Mrs. North will lay another egg. That’s up to her. While it may seem unlikely, just about the time you say probably not, something does. That said, we’re happy for the one egg laid and hoping for less drama as the season unfolds.

We’d like to thank our wonderful camera crews for their dedication and especially the overtime duty the past few days making sure we don’t miss a minute, and to the video makers who preserve the history with their films. And RRP greatly appreciates all of our volunteers who contributed their thoughts to this assessment.

Note: Robin Brumm put these caps together showing just how different an eagle can look depending on camera angle and the eagle itself. This is Dad Decorah on N2B. Robin took the caps seconds apart.

Two views of Dad Decorah