From RRP's Facebook page....
Raptor Resource ProjectIt was a rough weekend and start to this week for the Trempealeau eaglets. Yesterday, our camera operators documented Mr. T bringing fish to another nest. This morning, TE4 and TE5 died after Mrs. T left her nest to hunt in a cold, slashing rain. Bald Eagles usually take excellent care of their young and Mrs. T certainly did her best. What happened?
2024: First-Time Father?
We’ve had a lot of questions about Mr. T’s behavior. In 2024, he gave all the indicators of being a new eagle father: he seemed reluctant to feed his offspring and was less present for brooding, especially early in nest life. We were surprised and concerned when he disappeared on March 28, and relieved when he finally reappeared and began participating in nest life on April 6. In our April 8 NestFlix, we noted that: “A male eagle has returned to the Trempealeau nest. He’s (kind of) delivering food and taking a very occasional turn on the nest, although he hasn’t fed the eaglets as of this posting. Could he be a first-time father?”
We went on to talk about other nests with first-time fathers, including the 2024 Hanover nest, the 2021 Fort St. Vrain nest, the 2019 Decorah nest, the 2016 Decorah North nest, and the 2012 Fulton nest. The Hanover and Fulton nests failed when neither male helped care for eggs and young. First-time fathers Pa, Mr. North, and DM2 all brought in food and brooded, but it took a while for them to begin feeding and Pa regularly fed himself instead of his eaglets or Ma. So, case closed: Mr. T, a first-time father, would improve his parenting and relationship skills in 2025. Or so we thought.
2025: Two Nests?
At first, 2025 looked promising. Mr. T was attentive, Mrs. T laid three eggs, and both eagles took turns caring for their eggs and replenishing nest materials. But on March 19, Mr. T began spending noticeably less time on the nest. While it’s normal for female eagles to take on more incubation duties, the drop in his participation was significant enough that we took note. And on March 27, he stopped participating in nest life altogether, although our camera operators continued to see and hear him in the vicinity of the nest. He didn’t come back until April 5, when he flew in and began incubating the eggs:
https://youtu.be/hYILGV8Hh-o?si=6XXpamCZSaAlAQOuWhat happened? At first, we speculated that nearby construction might have spooked him. But we also couldn’t help wondering if he was involved with another nest, specifically one located on an island roughly 1700 feet west of the Trempealeau site. His nesting timeline and behavior only deepened the mystery, suggesting the possibility of yet another new male for the second year in a row. New male or another nest? We discussed our thoughts in a play-by-play with explore.org:
https://www.youtube.com/live/Uv091DbCZcE?si=9fSTSzQa1HkbpaEZ and blogged on the possibility of yet another new male here:
https://www.raptorresource.org/.../does-mrs-t-have-a-new.../Meanwhile, Mr. T showed up sporadically, vacillated between bringing food to and stealing food from the Trempealeau nest, and brooded TE3, TE4, and TE5 only occasionally. Camera operators in particular began speculating about another nest because, as one noted, 'he sure is an odd eagle'.
In the spring of 2024, we were restricted to one lower resolution camera, which made it hard to gather biometric data or follow the eagles when they left the nest. But we added a much better camera last fall. On Sunday morning, one of our camera operators captured Mr. T taking fish from the Trempealeau nest and flying over to what we’re calling the MN Island nest to join a female there. I was shocked, especially since the eagle thruples I’m familiar with involved multiple eagles in the same nest, not one male eagle provisioning two families.
In short, Mr. T had two nests and two eagle ‘wives’, or at least two female eagles he was interested in:
https://youtu.be/8bp-_oilfqc?si=82m8rMKzDuJS-lCdHere’s what we know
- There is a second female bald eagle on a nest located roughly 1700 feet west of the Trempealeau nest. Mr. T is visiting her with food gifts taken from the Trempealeau nest.
- The adult female eagle’s behavior suggests brooding. But distance and wind make it very hard to tell. We hope to get down there before the trees leaf out and make remote viewing impossible.
- Mrs. T nested here in 2024 and 2025.
- Mr. T helped Mrs. T respond to a threat after dark on April 19 and brought in nesting material and fish on April 18. But he took more fish than he brought in and didn’t share brooding duties. Mrs. T was left to handle the storm by herself. She did an excellent job, but it just wasn’t enough.
- Eaglets TE4 and TE5 died on the morning of April 21 following a day of soaking rain and cold wind. As of this blog, larger, older TE3 is still alive. The deaths happened very quickly: all three eaglets were alive and squirming at 5:25 AM and TE5 was dead by 8:00 AM.
Here’s what we don’t know
- Did Mr. T have another nest last year? We don’t have the detailed notes we took this year and were not able to see into the MN Island nest with the camera we had. However, the behavior recorded in our forum, blogs, and by video makers seems quite similar. We didn’t get a soaking multi-day rainstorm last year, which might be why both eaglets survived 2024 with very little help from Mr. T, other nest or no.
- Was Mr. T new last year? Is Mr. T new this year? I believed he was new last year and could have been replaced again this year. But the magic eight-ball has gotten very murky: his behavior was very similar both years and could be explained by a second nest, the nest chronology still points towards a new mate, and what biometrics we have are unhelpful. We don’t know whether or not he was new either year. We've included some captures for comparison. Feel welcome to give us your opinion.
We are not taking TE3 from the Trempealeau nest. Mrs. T is doing an excellent job caring for it, the eaglet turned ten days old today, and its thermal down is starting to grow in. It will have no competition for food and the area is rich in natural resources, including plenty of fish. The eaglet has a good chance and we don’t want to take that away from it, Mrs. T, or even Mr. T, should he return. We’ll cross our talons and add more to what we know about eagles as we watch.
Thank you so much for watching, sharing, learning, and especially for caring. Eagle life isn’t always easy, but we love them.
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Topic: Trempealeau Eagles 2025! (Read 7000 times)