Timeline of events
- 4/18/18: A serious snowstorm follows right on the heels of a three-day weekend storm. Mom and Dad spend the day caring for the eaglets, at times feeding and brooding them together in the nest. Dad is last seen on the nest around 7:30 PM. Mom broods overnight. We have been reviewing the footage to look and listen for anything unusual, but the process is time-consuming. We will let everyone know if we do.
- 4/19/18: A bright, sunny day follows the storm. We are a little concerned when Dad doesn't replace Mom for his morning shift, but think that he might be resting up from the intense flurry of activity following two large storms. As the day wears on without Dad, we become more concerned and begin making plans to go look for him. We see another eagle. Is that Dad? We send an on-the-ground observer, who tells us that Dad is there. However, Dad doesn't show up to feed the eaglets or give Mom a break.
- 4/20/18: We enter a second day without Dad. We are increasingly worried that something has gone wrong. Mom continues to care for the eaglets, who are stuffed to the point of bursting with nestovers and fresh-caught fish. However, she clearly knows that Dad is gone and at times seems very wary about activity near the nest. She peal calls throughout the day with no response. Our camera operators catch several glimpses of another eagle in the area. We determine it is a male eagle and designate him UME, or unidentified male eagle. Could that be Dad? If it isn't, why is Mom tolerating him so close to the nest? He spends part of the day perched above it and Mom at one point perches near him. If it is, why isn't he giving Mom a break, bringing in prey, responding to her peal calls, and harassing an osprey that has perched by the pond? Why does she seem so wary of his presence? Unfortunately, UME never comes close enough for a look at his iris, molt pattern, or foot scales. John launches a search of the hatchery and nearby areas with some friends, but doesn't find anything. Despite yesterday's observation, we become increasingly convinced (based on behavior and photographs) that Dad isn't here. After a consultation with our eagle experts, we announce that UME is not Dad.
- 4/21/18: John coordinates a search from the hatchery. 20 volunteers and a drone team from the Decorah Fire Department look for Dad. They search roadways around the hatchery, the bike trail, the stream, the area around N1, the hatchery grounds, hatchery buildings, and power poles and lines to the east. We don't find any sign of Dad. Meanwhile, Mom continues to feed the eaglets and we see UME fly on to the Skywalk and stay for about five minutes. Mom is agitated by the intrusion and remains wary of UME, although her peal calling has largely stopped.
- 4/22/18: Dad is still absent, another search doesn't turn up anything, and Mom is still wary of UME (who is still hanging around and does a fly through at one point). She feeds the eaglets throughout the day. While we worry, they have bulging crops and are developing on track: eating, sleeping, pooping, bonking, playing house, wingercizing, exploring their clown-clomping feet, and starting to grow pinfeathers.
Your questions
- QQ: Could UME have driven Dad away? Or did Dad leave because he was tired of caring or could no longer care for the eaglets after two big storms?
We talked with our eagle experts about the likelihood of both questions. It isn't unknown for new eagles to drive away territorial eagles, although we haven't seen displacement during the nesting season at any of our nests. We don't have any documentation of an adult eagle, male or female, simply deserting young, and Dad was caring for the eaglets up until the time he disappeared. Put simply, we don't believe that Dad voluntarily deserted the nest but we don't know where he is or whether UME had anything to do with his disappearance. After several days of terrible migration weather, birds finally got a break and were busy heading north. UME could have displaced Dad, or he may have been migrating through the area when Dad disappeared. Since there was no response to his tentative exploration of the area around the nest, he might have decided to stay and get a little closer. - QQ: What could have happened to Dad?
Our search was structured along the following possibilities: UME injured Dad in a fight (we searched around the nest with binoculars and checked the trail, stream, fields, and area around N1). Dad was hit by a car while eating or getting roadkill (we searched roadways and ditches). Dad was electrocuted on or collided with a powerline (we searched the base of poles and along powerlines). Dad got caught in a building (we searched hatchery buildings). We covered a lot of area with 20 volunteers and a Decorah Fire Department drone, but didn't find Dad. We still don't know what happened to him. - QQ: Is UME a threat to the eaglets?
This is a tough question. Anecdotes and scientific literature both contain examples of new adults killing eaglets and caring for eaglets. We are hopeful that he won't, given that he hasn't behaved in an aggressive way towards the eaglets or Mom. We're waiting to see if he brings Mom any food or courts her. - QQ: Are you going to pull the eaglets from the nest?
We are not. From a human perspective, we would be caring for the eaglets by keeping them safe from hunger and predators. But from Mom's perspective, we would be invading and killing her eaglets. Mom is far more capable of caring for her eaglets than we are, and we have no plans to take her young from her. - QQ: So Mom can feed the eaglets by herself?
Mom has fed the eaglets to bursting multiple times every day since Dad disappeared. Between the hatchery and the stream, she is more than capable of keeping them fed. - QQ: I saw that Mom was attacked by a bird. Was that an eagle?
Mom was being swooped by crows earlier today. We've also seen starlings and nuthatches steal nesting material and search for food. All of this is completely normal behavior and has nothing to do with Dad being gone. - QQ: Mom seems really wary and watchful. Why?
Mom is probably responding to UME, who as of this post on April 23rd was still in the area. While he hasn't treated her aggressively, he still isn't her mate and she is usually very wary when he comes near the nest. We've only seen one exception, which happened on Friday, April 20, when she perched near him. - QQ: Could this be Mom and Dad's offspring from another year?
While it could be, we have no way of knowing one way or another. - QQ: How old was Dad?
We don't know, but believe him to be at least 21 years old based on his plumage and when we first started watching him.. Is it possible that he could have been less cold-tolerant because of age? We're asking our team on that, but we don't know at this point.
Thank you for all of your care and kind comments. We know this is hard on everyone. We promise to keep you all posted.
