Sunday, September 17, 2023

How Common Are Boreal Owls in Utah's Uinta Mountains?

Boreal Owl in Utah's Uinta Mountains

After surprising success with finding three Boreal Owls during my first attempt to locate them in Utah's Uinta Mountains in October of 2020, I began to wonder how common they might be in the high-elevation forests of Utah. I had read and studied numerous articles about Boreal Owls and noticed that Colorado and Idaho populations were often discussed. Utah was noticeably missing from many of the articles I read. The Uinta Mountains of Utah seemed like a natural bridge between the Colorado and Idaho populations, but I was having a hard time finding studies that had been done on Boreal Owls in Utah.  I wanted to know more, so I began to consider how to go about a personal endeavor to learn more.

The preferred Boreal Owl habitat in Utah seems to be above 9000' and is often inaccessible to vehicular traffic due to heavy snowfall between November and late spring. Male Boreal Owls are most vocal when establishing their breeding territories and courting their mates, so I decided that I'd try finding them again as soon as the roads opened the following spring/summer. Unfortunately, I failed to locate Boreal Owls when I drove up to proper habitat the following June. I didn't hear a single sound from any species of owl that night despite playing some recordings of several types of vocalizations. A second summer trip proved unsuccessful in terms of locating birds, but it taught me a few things about conditions that may be unappealing to Boreal Owls. After doing a little more research, especially making use of my subscription to The Cornell Lab of Ornithology's Birds of the World, I learned that males generally stop singing on their territories once they have a female using a cavity for nesting. Except for minimal contact calls and some vocalizations when the male is delivering prey to an incubating or brooding female, the birds are quiet. That makes them very difficult to locate in sprawling dense coniferous forests in the Uinta Mountains.

A third trip made during September of 2021 proved successful. It seemed to confirm that birds are  more prone to vocalizing in response to calls during the fall. As was the case the previous fall, I found multiple birds in close proximity to one another. That is when I began to wonder if I was finding family groups that were dispersing and if most of the vocal birds might be hatch-year birds and parents communicating with one another. The plumage always appeared adult-like, but I suspect that hatch-year birds are coming into their adult plumage by that time of the year if they hatched five or six months earlier.

After locating birds two falls in a row (2020 and 2021) and reporting them on eBird, the location where I originally found the first three was becoming more widely known and visited more frequently by local and out-of-state birders.  That's when I decided to develop a plan to plot four new locations that looked promising based on elevation, tree mix, and barriers to human traffic. I then shared the plan with a couple of friends and invited them to join me in an effort to prove to ourselves that the lack of Boreal Owl observations in Utah stemmed from more of an access challenge than a lack of their presence. The three of us wanted to prove that Boreal Owls were more common in Utah than birders and others realized. Perhaps our results and documentation would lead to having the species removed from the list of rare birds that get reviewed and validated by the Utah Bird Records Committee.

One of the friends I teamed up with was an eager driver with no fear of putting a fair amount of wear and tear on his tires and suspension as we traversed very rugged terrain.  The "Rocky Mountain pinstripes", courtesy of the many tree branches extending over the unmanaged rough roads, seemed to be part of the price to make exciting discoveries. The other friend is the one who inspired me to begin my Boreal Owl endeavors when he located and photographed a Boreal Owl a few months before I found my first three in the Uinta Mountains. We became the three Boreal Owl amigos and logged hundreds of miles, many hours, and late nights to create bonding conversations and experiences. It turned out that we found Boreal Owls in each of the four new locations that I had mapped. We found them on the north slope, two locations west of Mirror Lake Highway (one on the northern end and the other on the southern end), and a spot above Soapstone Campground. We found them along Murdock Basin again the same fall.

We observed over twenty different Boreal Owls in the fall of 2022. While we aren't biologists, we did our best to document location, time, weather conditions, moon phases, and counts of individual birds. We photographed nearly every bird we found and in most cases we found two or more birds in each location. Whenever we located birds, we would drive at least a half mile or more before attempting to check for the presences of additional individuals.

We realize that populations can be cyclical and that we were primarily in the western portion of the Uinta Mountains, so we have plans to investigate other locations in 2023. I'll be sure to report on our findings.

Below are some images of a handful of the more-than-twenty individuals we observed during the fall of 2022. All of our encounters and details are recorded in eBird checklists.

More to come.

Boreal Owl in Utah's Uinta Mountains

Boreal Owl in Utah's Uinta Mountains

Boreal Owl in Utah's Uinta Mountains

Boreal Owl in Utah's Uinta Mountains

Boreal Owl in Utah's Uinta Mountains

Boreal Owl in Utah's Uinta Mountains

Friday, February 17, 2023

That is Not a Flicker! Owl Box Success Story


The motivation to install a screech-owl box sprang to life late one night in September of 2020. I had just finished a late-night call with one of my sons when a faint but familiar sound from the backyard caught my attention. I wasted no time in securing a flashlight and making my way to the backyard to hunt for a Western Screech-owl. To my delight, I discovered a pair of them calling from separate trees and joyfully stood below one a moment later.

The encounter brought to mind that I had found one roosting in one of our redbud trees above some bird feeders a few years earlier. I began to think that might be able to install a box and get one to roost in my yard for the winter...and I knew just the right spot. I got way ahead of myself in that moment and envisioned a male finding the box, attracting a female to it in the spring, and keeping watch over his mate and littles ones from inside a nearby spruce tree. I had nothing to lose by planning and executing so I collaborated with another Utah birder who'd already experienced success with screech-owl boxes, and the plan was hatched!

Speaking of plans, I found some online for how to build a nest box, but my sense of urgency outweighed the experience of building a box. I received a box within days of placing an online order. I knew that hatch-year owls, hatched earlier in the spring, would be dispersing from their family groups during the fall, so it was clear that sooner would be better than later for increasing the odds of a bird finding and using a box for the approaching winter months. 

I purchased supplies from our local Home Depot. Shortly after giving myself a minor flesh wound inside the store and getting some first aid supplies from one of the store clerks, I was bandaged up and commencing my project on our patio. Apparently, the metal brackets that I picked up for securing the box to the top of a pressure-treated 4x4 post had some pretty sharp edges or burrs on them. Whoever machined those things in the shop didn't seem to have consumer safety in the front nor center of their minds when they created their master pieces. I had to make a joke of the mishap when I realized that simply applying pressure wasn't going to stop the bleeding. I was wondering if I might have to request the proverbial "wet clean up and aisle 10", but the clerks were pleasantly entertained by my predicament and retrieved a first aid kit. I digress.

Here are some images of the process from receiving the box to digging the hole and setting the post in quikrete to affixing the box at the top of the post in a quiet and inviting location in the yard.  I can share tips should you ever decide to put up a box in your yard.





Fourteen months and who-knows-how-many glances in that general direction after installing the box, I saw my very first desired resident. I was so relieved when I looked back in that corner and proclaimed, "That is not a flicker!"  The nearby conifers turned out to be a day roost at times for an owl and the preferred preening location after an owl left the box to begin its evening activities.

Sleepy Western Screech-Owl Soaking up Some Sun

I was pretty excited to have what I believe to be the same owl return to the box again the following November (2022) through mid-February of 2023. Despite putting up a second box the previous fall and having a male and a female use the boxes at the same time for a few weeks this winter, they seem to have disappeared in favor of an alternative nesting site in recent weeks.

This story will continue should one or both choose to return. Until then, enjoy the birds and wildlife that grace you with their presence.

Tuesday, October 13, 2020

What's Wrapped Up in a Boreal Owl Pellet?


Boreal Owl Pellet
Wasatch County, Utah

(View on a large screen and click each image for a higher resolution view)

Why Pellets?

Well, here's a close up of the Boreal Owl pellet I retrieved after one of the owls in my last post hacked it up, briefly clutched, and then dropped it to the ground. This one-inch (2.54 cm) pellet came from an owl that is between nine and ten inches tall (22-26 cm), depending on whether it was a male (smaller) or a female (larger). 

You may already understand the process, but I want to share with those who may not know how a pellet is formed and why it is expelled. Owls, and many other birds, have two stomachs or chambers that aid in the process of digestion. They swallow prey whole or in chunks, but they cannot digest the fur, feathers, teeth, nails, or bones of the prey. The first chamber essentially liquifies the digestible parts with enzymes and sends the partially digested meal to the second stomach, or gizzard, which breaks down the hard pieces, sends the digestible contents to the intestines, and compresses all the useless stuff into an oval shaped pellet. The owl has to regurgitate the pellet from the gizzard before the next meal so this process of creating and casting pellets typically cycles once each day. Many owls cast their pellets from their daytime roosts so locating pellets below trees, particularly conifers, or cliffs and manmade structures such as barns and silos is one way to discover their roosts. 

When I realized that one of the Boreal Owls I was observing October 3rd was about to hack up a pellet I began capturing a series of images as quickly as I could. The image below shows the owl manipulating the pellet before dropping it to the ground.

This Boreal Owl expelled the pellet, grasped it, held it to its bill before dropping it to the ground.
Uinta Mountains, Wasatch County, Utah

Finding this species of owl, considered rare in Utah, was special. Watching one actually cast a pellet was extra special so I considered the pellet a parting gift to memorialize our time together. Drying it out and inspecting its contents struck me as a great way to learn more about the the diet of the owl. Boreal Owls are perch hunters so they wait for prey to appear and then swoop or drop down to take prey with their talons. Small mammals such as voles, mice, and shrews along with small birds and some insects make up the bulk of their diet.

Let the Inspection Begin

The pellet was set aside for a few days before I got around to unveiling the contents and capturing images with a macro lens. Mounting the camera on a tripod would have yielded crisper images, but handholding seemed to meet the need well enough when I added a flash and diffuser to the mix. I probably should have used a solution to remove all the fur from the bones, but I didn't. I kind of sound lazy with those explanations, but I was just really curious about the contents and my casual approach satisfied that curiosity well enough.

Pellet Quiz Time

The anatomical parts seem to belong to at least two mammals (voles?), because I can see jaws and hard pallets for two mouths.  What rodent do you think is represented in the images? I forgot to use a ruler in this image to show scale, but all of it fit into that one-inch pellet shown at the top of this post. The jaw bones were probably 3/4 inches (1.9 cm) long. What parts can you identify before looking at the illustration I've created in the very last image? Please tell me in the comments if you see more identifiable parts and I'll try to add them to my labeled illustration.

Click on each image for a higher resolution view.

Drum roll! And the answer is (with a little help from my veterinary friend):

Saturday, October 10, 2020

A Series of Boreal Owl Encounters

Boreal Owl in the Uinta Mountains in Wasatch County, Utah
October 3, 2020

Let the Utah Boreal Hunt Begin

Hello, friends and nature lovers! A little over two years ago I presented myself with a "lifer" choice that would either have me driving two-plus hours to the Uinta Mountains in northeastern Utah or three-plus hours to parts of the Colorado Plateau near Moab, Utah.  "Lifer" is how birders and herpers (reptile and amphibian seekers) refer to a species observed for the first time. In the Uintas I would look for my first-ever Utah Boreal Owl, a rare species for our state. In the Moab area I would go looking for Eastern Collared Lizards. It was mid-summer so it was kind of a choice between the cooler temps of our mountains or the warmer temps of the desert. Reptiles had captured my attention at that time so I chose the desert. I went and had a wonderful time sleeping under the stars and finding and photographing the lizard the following day. I've shared that experience in a previous post found at this link.

Two weeks ago my wife and I did a trip to Yellowstone National Park. Prior to that trip the two-year-old Boreal Owl itch returned so I decided to scratch it by adding an hour or two of owling to the trip.  I would have loved spending more time owling during our evenings, but it was a trip for "us" so my birding interests were barely on the radar for by non-birding spouse. Limited time required me to be efficient so I studied Google Maps before the trip and paid close attention to habitat and location as we drove into the area.

After some downtime at the hotel on our last night of the trip I received the "okay" to venture into the dark for owls. I drove to a dense pine forest with sporadic meadows outside of West Yellowstone. As an FYI, I drove to that location because I had planned to play calls to locate a bird and national parks prohibit the use of recorded calls to attracts birds. The Proper Use of Playback in Birding by David Sibley provides guidelines for using calls to attract birds.

It was quiet that evening on the road I chose, not a single vehicle drove in my direction. I played a Boreal Owl song for about twenty seconds and then listened and waited for a few minutes. With no evidence of an owl being present I tried the process a couple more times. I did this at several stops without getting any indication of an owl's presence. I used my light to scan the trees around me with no success. I drove to what would be my final stop and was again met with utter silence. I gave the surrounding trees one last look before getting back into the car and that's when this little creature appeared in my view. It was perched in a tree about forty feet away.

Boreal Owl near West Yellowstone, Montana
September 29, 2020

That little owl, standing about 9-10" tall, depending on whether it was male or female (males being smaller), had come to see who was calling without ever making a sound. It was one of the "silent observers" as I call them. 

It was an amazing experience, for which I was incredibly grateful. I gave a verbal thank-you to the owl before departing. It was my second Boreal Owl ever and the first one that I was able to find on my own.

Boreal Owl Near West Yellowstone, Montana
September 29, 2020

Time to Find a Utah Boreal Owl

The success of my first Boreal hunt propelled me to develop a plan for finding my first Boreal Owl in Utah.  Prior to leaving for Yellowstone I talked with a friend who had encountered a Boreal Owl in a remote location of the Uinta Mountains at the end of August. I wanted to get a description of habitat without knowing the specific location. I don't ask other birders or photographers for specific locations of the rare species they discover for two reasons. First and foremost, it avoids putting them in an awkward position when they are uncomfortable with having to say no. Secondly, I actually enjoy the process of learning and discovering things on my own as much as possible. I find great satisfaction and joy in the process of learning, exploring, and discovering for myself what nature has to offer. Capturing images as a result of that process often provides nice memorials for those experiences so I do try to get quality images when possible.


To prepare for my Utah search I reviewed the handful of eBird reports of Boreal Owl sightings in the Uinta Mountains, spoke with a biologist who has some experience with the species and studied range maps, habitat, and recordings of their vocalizations online. Some range maps showed a thin slice of the range passing through the Uinta Mountains and others showed the Boreal Owl range skirting around Utah from the Rocky Mountains in Colorado up to Wyoming, Montana, and Idaho. The Uinta Mountains are considered to be on the fringe of the normal range so it began to feel like I might be searching for a needle in a haystack, but that just made the adventure all the more enticing. For additional intelligence I spoke with a couple of local birders who had recently returned from unsuccessful searches in the Uinta Mountains. They generously provided information regarding the terrain that I would need to traverse in the search I was planning. High clearance, durable all-terrain tires, solid suspension, and 4WD would be required. I heard in my mind, "Don't try this at home, kids!" Neither a sedan nor even a small SUV with highway tires would be well suited for such an endeavor.  The location would not be a good place for a breakdown, nor to simply get stuck in a rut, because much of the area is outside of phone service. With all that information I was ready to begin my search and try to answer my question about how common or rare the species really is in the Uinta Mountains.

Success in the Uinta Mountains!

I set out on my first Utah Boreal Owl hunt October 3rd, 2020. I made it to my starting point during daylight to explore some of the more remote and risky routes in the area. That was a good thing because I lost Verizon service on my phone and was unable to continue viewing the targeted spots I had marked on a personal Google Map. It didn't take long to realize that the roads were rougher than all previous routes I'd taken for owls in other remote mountain locations. I saw lots of great spots to check, however, as I drove deeper into the area. I decided to turn around at one point because I felt like I was in a small boat being tossed to and fro on a roaring sea as I was bounced and tilted side to side from boulder to rut while advancing at a snail's pace. I had already passed through good habitat and it seemed unnecessary to risk the additional wear and tear on my Tacoma.

I stopped as the sun was setting to enjoy the scenery.  It was deathly silent until a Northern Pygmy Owl called from a distant perch and some Mountain Chickadees came in to check me out as I mimicked the call of the Pygmy-owl.

Darkness increased and signaled the time to begin the real hunt for my first Utah Boreal Owl.  I don't know if I got super lucky or if there are more Boreal Owls than we think, but I was able to find my first one after two stops and within seconds of attempting to call for one.  My heart pumped with excitement as I quickly fired off a few fames to document the encounter. I could not believe that the moment had arrived so early in my search because I had prepared myself to return home without seeing one. To my delight, the bird was accommodating and allowed me to capture better images and a brief recording of one of its vocalizations.

Boreal Owl in the Uinta Mountains in Wasatch County, Utah
October 3, 2020

Boreal Owl in the Uinta Mountains in Wasatch County, Utah
October 3, 2020

Once again, I expressed gratitude to the owl before parting. I could have called it a night early and headed home with a great feeling of achievement, but I was then more curious than ever to see how easy or challenging it would be to find another owl. Little did I know that I would choose to stop in a subsequent location that produced two Boreal Owls. They appeared to be a pair, a smaller one presumed to be the male and a larger one appearing to be the female.

Boreal Owl in the Uinta Mountains in Wasatch County, Utah
October 3, 2020

Boreal Owl in the Uinta Mountains in Wasatch County, Utah
October 3, 2020

These two birds vocalized what struck me as contact calls intended to communicate each other's location. The male issued a soft but high-pitched squeak or hiss and the female responded with a slightly louder "wert" call.  Here is a link to the recording of the  Boreal Owl Pair Calling.  The audio file is stored on my Google Drive so if you have the Google Drive app it will probably play well for you. It may help to turn up your volume when you listen to the recording. And, depending on your device, you be required to download the file to hear the soft calls. 

As I was photographing one of the owls it leaned forward and rotated its head side to side a couple of times before expelling a pellet, which it then grasped and held in a talon.

Boreal Owl Casting a Pellet
Uinta Mountains in Wasatch County, Utah
October 3, 2020

Boreal Owl With a Pellet in the Uinta Mountains in Wasatch County, Utah
October 3, 2020

The owl eventually let the pellet fall to the ground and then I retrieved it before leaving the scene because I wanted to take it home, dry it out, and inspect its contents. I saw it as a way to learn a little bit more about the owl I had observed. I'll publish the results of that inspection in a future post.

Needless to say, I was beyond elated with the surprising results of my first Utah Boreal Owl hunt. It was a Boreal Owl bonanza beyond any expectation. I am incredibly grateful for seeing three owls, recording a calling pair, and watching one of them cast a pellet, which became a parting gift of sorts. 

Thank you for visiting my blog and sticking with me through this long post. I hope you enjoyed it and learned something new. May you have safe and excellent encounters as you venture into nature.

Additional resources to learn more about Boreal Owls: