Tracking Down This Great Horned Owl

I’ve gone back to the spot I first found the great horned owl now several times, at the same time of the evening, and birded around there in the evening many more times to no avail. I did talk to someone down at the Loon’s Foot Landing ore dock who claims an owl comes around “once a year” and hunts from the ore dock. He said it hunts pigeons, and will sit on the dock to eat its kill. This is right across the street from where I saw the owl, so let’s assume it’s the same one. I’ve since looked around the area extensively for nests, and now have my ears out for fledglings, but no luck so far.

Let’s assume the great horned owl I found was an unsuccessful male. I don’t have much to go on for that assumption, and it very well could be wrong: I’ve never heard any calling in my block, and you’d think an unpaired male would be more vocal later in the season. I made a possible home range map based on the measured spring home range for unsuccessful males in Wisconsin: 279 ha (Petersen & Nehls 1979). I did the “full spring” range because I’m not sure when the ore dock sightings occurred. I also put the known locations at the western periphery, because several repeat visits didn’t yield a sighting of the owl (though this could be wrong because often the full home range isn’t utilized, especially in spring), so perhaps it’s found in those places infrequently because those locations are more toward the edge of where it hangs out.

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With hopes it hangs out somewhere in the bounds of my block, and based on previous years’ sightings, this could roughly be its home range.

I put the sightings at the western periphery so that the home range was more in the block.

Literature Cited

Petersen, LeRoy R.; Nehls, Susan, Editor. Ecology of great horned owls and red-tailed hawks in southeastern Wisconsin. (Technical bulletin. (Wisconsin Dept. of Natural Resources), No. 111) Madison, Wisconsin: Wisconsin Department of Natural Resources, 1979. 63 pgs.

Looking for Nocturnal Species for the WI BBA

Today, I went back to where I found the great horned owl. I didn’t find any new nocturnal species, but I did find white-breasted nuthatches carrying nest material in the late morning! I also found what could be a large nest, but it’s high in a pine tree and thus difficult to fully see. I’m unable to get a good look into what might be a nest, and returning to visit in the evening yielded no activity around the site. I want to trek back to where I think the owl landed earlier in the week, but I’ll likely need sturdier field clothing to make it through the vegetation.

I’m curious about the drainage stream that run parallel to 24th street. Is there anything interesting that hangs out in that small, man-made (or at least enhanced) water feature? It looks like it was a ditch created for the sake of the railroad tracks. I also still don’t know what the seeming natural area is that is between Enbridge property and the Nemadji River.

Nocturnal Surveying for the WI BBA

Tonight, I found a great horned owl that flew in from over a treeline from some northwesterly direction, perched atop a tree near where I was parked, and then flew off to hunt. It was descending as it flew off, so that’s why I guessed it had heard something and was going after prey. Since it was descending, I made a guess as to where it landed, though it flew out of sight. I was so excited because I’ve been looking for this species in my block, but it gave no clue as to if it was actively breeding.

Finding Nocturnal Species for the WI BBA

I did finally get on the board with some nocturnal birding, in the form of displaying American woodcocks at dusk!

Meanwhile, some of my friends relocated the American three-toed woodpecker(s) today at the spot down the road from where I was looking (i.e. the traditional spot). The original finder had them back there a few days before, and another friend joined them to see them.

Why I Love Being a Primary Atlaser

One cool thing about coordinating a Breeding Bird Atlas (BBA) block, like several other citizen science initiatives, is you develop a sense of “place.” I’ve visited Superior, WI and Duluth, MN (and beyond) as part of the same trip several times before I moved up here, so I inevitably associate the Twin Ports in my experience. I moved to Duluth, MN last fall, and picking up the nearest available BBA block has given me occasion to do what I like to do best: walk around and look for birds, most commonly, around sidewalks. I’m responsible for the Superior CE block, which means the burden falls on me to make sure it’s completed. I used to participate in the WI Big Green Birding Year; I found quite a bit of joy just getting to know my neighborhood better, especially since I moved almost annually in Madison. Picking up this local block here up north has given me the same opportunity to get to know my new home (well, in this case, the twin port) better.

Coordinating a block doesn’t mean I have to complete it single-handed, and since I picked it up late (it’s year 3 and still needed a coordinator by the time I moved here) there have been plenty of contributors. In fact, by the time I got here, there had been 13 of the requisite 20 hours already logged. I’ve done more than the 2 required night visits, and all I need to do is finish out the time birding (which is easy, and technically needs only to be completed sometime within the next 2 years), or ensure that others do.

Yet, it’s inevitable that you develop a sense of pride about “your” block, and I think it’s an incentive to bird there. Like many other coordinators, I’m thus far aiming “above and beyond” the requirements to find as many breeding species as possible. My personal interest is to even find some in as many spots as possible, such as American woodcock. In the process, you learn more about habitat associations, which brings out the always-learning component of birding that keeps you coming back. Initiatives like these have a way of rekindling your curiosity, and by nature, require you to pay closer attention to behavioral details. It gets you back to the “roots” of birding and nature observation.

It has led me to more detailed birding of an area that in general is little birded, and highlights spatial bias in e-Bird. For instance, I have a famous hot spot in my block, and by-and-large most observations are from there (or on the way). So, I have the satisfaction of reporting species in places they’ve never been reported before, because people don’t often go to those areas to bird. It thereby produces more detailed data at a finer spatial resolution for e-Bird, and fills in “gaps” of areas that haven’t been (or at least have infrequently been) surveyed. To that end, I think the BBA is succeeding in its sampling design aims, to gather more data across a particular area.

Owl e-Bird Records for my Block

I’m grateful to the hard work of the coordinators for entering the data from the previous iteration of the Breeding Bird Atlas! I can see that a great horned owl nest, the species I’m looking for, was found in the block last time around. All of the other owl records in the block are on Wisconsin Point, unsurprisingly. It’s easy to see the spatio-temporal bias in the data here: most bird reports in general for the block are on the point, during jaegerfest! Looking at the data at this particular spatial resolution really highlights an issue like this, and is a nice “effect” of this kind of randomized sampling.

My WI Breeding Bird Atlas Block: Superior CE

To aid in planning to survey my block, particularly for nocturnal visits, aerial photos are a big help. Great horned owls are quite generalist when it comes to habitat. I’ve seen them in urban areas, perched on buildings in spaces that had nearby big trees, and on light posts on the edge of a parking lot. They also nest in nest boxes on tall buildings, and in urban green spaces. The only nest I’ve personally seen was in an oak on a small savanna on campus, which is fitting with the Birds of North America account that they prefer oak and elm in Wisconsin.

Because of their readiness to colonize human-dominated habitats, they have expanded their range and have gotten into areas where they weren’t before, sometimes at the expense of other species. A friend in the birding community actually told me that they’ve been removed in areas within my block to protect a tern colony, so it will be interesting to try to find out what their current distribution is in the area. It also brings up a bit of an ethical dilemma for me: it’s unpleasant to think about “predator control” for native birds, but I also see how we have allowed great horned owls to take hold in areas they may otherwise not exist in such density. How would I feel if I reported a great horned owl, and it was killed because of it?

Wisconsin Breeding Bird Atlas Block

I had a great horned owl calling outside my apartment in the early morning hours (12:39 AM), which prompted me to make my 1st visit to my atlas block tonight. It was mostly getting familiar with my block, and making the labeled points on the featured photo. Right now, my main target is indeed great horned owl, since it should be about the peak of their breeding activity.