The Eagles Have Landed

Even though I’ve lived in Northern Wisconsin for 5 years and have seen many, many eagles, I’ve never come across a nest. Until now.

Not having paddled the Rainbow Flowage before, I decided to give it a go and soon I heard the distinctive rusty-gate call of a juvenile bald eagle. It didn’t take long to find it –

Right there on the very edge of the water a few dozen feet up. Wow. I was gobsmacked as they say. I’ve never seen wild eagles on a nest before and it was mesmerizing. I was with my friend and she was overjoyed as well. We talked a lot on approach, but then drifted apart and grew silent, just watching and feeling the special joy this species brings. Not long ago they were on the brink of extinction, and while not out of the woods yet (lead poisoning is a huge problem with these and other fishing raptors), they are more numerous and prospering in almost every part of their range. After a while we left them in peace and paddled on. But on the way back, we stopped again. This time mom was in a tree a few hundred yards away. We spooked her out of another tree and watched her fly to this one.

She is facing the nest and she and junior didn’t take their eyes of each other. Well, except to look at us once in a while. Again, we separated taking in the sight. I found that drifting quietly to the trees they sit in works to get close without scaring them. Noisy paddling or loud talking usually makes them fly off. We spent about 30 minutes with mom and she didn’t move or become alarmed. Since it was getting late we decided to head for the take out. As we did, we heard another eagle calling. Turns out it was dad –

We didn’t see the three together, unfortunately, but having seen mom so recently made us realize what a size difference there is between males and females. Males are smaller. This one let us get close using the same quiet method, but eventually flew off. Even though I don’t think he could see his mate since she was behind some trees, he flew straight to her. In retrospect we should have paddled over, or at least I should have to see if I could get a shot of them together. But I didn’t and we left, feeling joyous that we’d got to meet them and they let us hang around.

That was really something, but I doubted I’d see them again often since the lake is over an hour from the house. Too bad I didn’t know of a nest closer to home. Preferably somewhere remote and relatively quiet.

Like say…the Spirit river.

OMG. This is crazy. Check this out –

This is on my beloved Spirit just about 8 minutes from where I launch the boat.

Seriously.

I’ve passed by it many times without even noticing. Doh!

This time I’d gone downriver to explore backchannels and while I was coming back up, I heard that rusty-gate screeching. This time a lot of it. Constantly. And since I’d seen an adult not long before, I knew there had to be a nest with young ones. Keeping one ear on the noise, I paddled towards it and came to a big open area through some trees. Ahead and high up, there they were. Two of them this time. Healthy and vigorous. Almost ready to fledge.

These are the only two images I have that are worth a damn. The light changed drastically in the 90 minutes I sat in the boat, caught in some smartweed to hold me in the stiff wind. Alas, the parents didn’t come. Maybe I was making them nervous. The kids quit their racket and were quiet. At first the one stretching was in the nest with only the top of its head visible. Eventually it came out and they climbed around the nearby branches. I managed to catch this stretch, but it’s not tack sharp. The number of losers in my session made me upgrade my lens. That and the ease of reaching and watching this nest again. Now I know where it is, and that it’s at my favorite paddling place, will make me visit again and again, watching future generations of eagles grow and prosper. What better thing in the world?

What better thing? That the kids have fledged and when I went back in September they were high up in a tree, still together, yelling their heads off. I was with my friend again and earlier we chased one of the adults down river a bit and then found them right near the nest!

Both of those shots were taken with my new Leica-Panasonic 100-400 mm zoom lens. Much higher quality and a bit more reach. I’d been practicing with it before running into these guys again and I’m glad. I have more keepers with this lens, but these are the best images. Check out how dad has his head turned all the way around to look at us in our kayaks. Too funny. With them side by side you can see the difference in size – that’s mom on the left in the shot above, and on the right in the first one.

Oh and I found a third nest! My friend and I went to another flowage on another river and the nest was on a side channel. Judging by the rest of my time there (and a subsequent visit), it’s going to be a favorite. This time all the eagles were out of it including any of this year’s babies. A juvenile was circling overhead and so I have to conclude that it came from that nest. Eagles don’t tolerate others in their territories. But they are remarkably ok with humans, so I’ll definitely be back!

Why they’re eagle eyes

Stare at one particular word in a paragraph on this screen or on a page in a book or magazine you have to hand. Now try to read the words around it without moving your eyes from your target word. No cheating! Hard to do isn’t it? The pinpoint focus area is possible because of a structure in the back of the eye called the fovea. It’s a little divot that has more light sensing cells than the rest of the retina. Humans have one in each eye pointing directly ahead, and a visual field of about 110 degrees, most of which is visible with both eyes at the same time. This overlap is called binocular vision. Our eye placement means we have a generous field of binocular vision.

Eagles have nearly 360 degrees of visual field, but only have an overlap of about 20 degrees with both eyes. So most of it is peripheral vision not binocular. So how do they see so well? Because they have evolved two fovea per eye. They point in different directions. One set of fovea points straight ahead and the other about 45 degrees out to the side. It’s the second that has the highest acuity – it has the most detail. As the bird moves its head, it locks onto a new visual target, but still can see clearly with that second fovea. No wonder they never miss a thing!

Thus endeth the lesson!