Back in early May I had headed to the Biggest Week in American Birding (BWIAB) Festival with Jack and Janet Volker. The Volkers are impressive world birders and had been quite active with the development of the Ottawa National Wildlife Refuge (through the Friends of Ottawa NWF) for many years, donating their time and resources helping to build and improve habitat at the refuge. In the early 2000's Jack had a Barn Owl nesting box built, and installed it in a barn at the refuge after Rebecca Lewis, Refuge Biologist, had reported that a Barn Owl (roadkill) was found near the refuge. Over the years the box was used by Eastern Screech Owls and European Starlings, but largely forgotten since no Barn Owls had been seen in the region for many years.
That all changed earlier this year when a visitor to the refuge asked Rebecca to identify an owl he had photographed atop the barn. It was a Barn Owl! After inspecting the barn and the nest box Rebecca notified Jack that a pair of Barn Owls were using his box and had laid 6 eggs! With the BWIAB Festival going on next door at Magee Marsh word of nesting Barn Owls at Ottawa NWR could be detrimental to their success so everyone agreed to keep the news quiet. As he gave me a tour of the refuge he mentioned that he might have an opportunity to photograph some Barn Owls "nearby" and would I be interested in tagging along. I promised to keep the offer quiet and soon forgot about it after he and Janet took off for their trip to Malaysia. By the time they'd return any Barn Owls would be long fledged...
Fast forward to this past Sunday when Rebecca notified Jack that six nestlings had indeed hatched and that they were still in the box and now banded. Report was that the birds were ready to fledge and that one bird had already left the box. Jack requested permission for him (and me) to go down to the refuge after dark to attempt to photograph any fledging Barn Owl chicks we might see leaving the box. We agreed to try for this evening.
As we drove to Ottawa NWR we all expressed some concern that the owls could have left the nest box last evening (Monday) so we kept our fingers crossed that some of the chicks may still be around. Parking at the entrance to the refuge we unpacked our cameras and tripods and walked past the entrance gate toward the barn. So as not to disturb any potential Barn Owls in the area we set up our gear in the low vegetation across the road from the barn. I would be shooting a Sony a1 + Sony 600mm f/4 GM OSS lens + 1.4 TC for an effective focal length of 840 mm. With the additional APS-C mode I could add a 1.5X crop to my images for an EFL ~ 1260mm. Because we'd be shooting in low light I used a Sony RMT-P1BT Wireless Remote Commander that would allow me to adjust focus, capture images and/or videos without touching the tripod setup; it would prove invaluable...
Arriving just minutes before 8 pm we were set up and now waiting for the Sun to set. Our views were similar; Jack had his Nikon Z9 and 600mm f/4 lens and tripod (sans remote). My camera was set to Auto ISO with a minimum shutter speed of 1/2000 sec. with a maximum ISO of 12,800. At 8 pm my viewfinder would be showing 1/2000 sec. at f/6.3 and ISO 3200. In full-frame mode my view of the barn appeared as below: we could see the hole, a vertical beam inside, and spilled mulch on the roof below the hole. We could not see any activity in the hole.
9 pm came and the Sun was now below the horizon. Still no activity. Staring at the camera viewfinder in low light produced nothing. Any perception of movement was attributed to probable eye-floaters.
However, at 9:01 pm, while we sprayed ourselves down with DEET while being swarmed by mosquitos, I caught movement in the hole! It initially looked like a white feather poking into view from the right side, but it turned out to be an owl face. Barn Owl face! The camera was now showing 1/640 sec at ISO 12,800. Despite the disappearing light we could focus and photograph.
At 9:15 pm the camera was now reading 1/125 sec at ISO 12,800 but was able to detect a second face tucked in the rear of the hole. If you look closely you can see a faint owl face behind the owl on the right.
At 9:20 pm the second Barn Owl appeared; this bird appeared to be younger than its sibling. The camera was now reading 1/60 sec at ISO 12,800. Both birds were quite active bobbing their heads in order to gauge depth of field of their outside world. They put on quite a show!
Finally, at 9:30 pm, it was completely dark. Only the camera's electronic viewfinder was sufficient to show the hole and a young Barn Owl that had finally stuck its head out to view the outside world. I was now shooting at 1/6 second. Thankfully, the Sony RMT-P1BT Remote was allowing me to capture images of the owl when it paused its motion long enough for a sharp image.
At 9:31 pm the second fledgling tussled with its sibling for control of the hole. It temporarily lost the battle. I was now shooting at 1/5 second at ISO 12,800.
With the camera now reading ¼ sec. at ISO 12,800 one of the fledglings finally stuck its head out of the hole and began to peer around. We were now looking at more than just a facial disk. It was 9:33 pm.
Finally, at 9:39 pm, with the camera giving me ½ sec. exposures at ISO 12,800 the first fledgling left the hole and fluttered to the roof immediately below. Despite the horribly slow shutter speeds I managed to get a few pics when it paused motion long enough for a sharp exposure.
As fledgling number one scanned its new surroundings and evaluated its home from the outside fledgling number two appeared in the hole.
After a few moments fledgling number one fluttered to the left side of the barn under the large sign while fledgling number two prepared to leave the hole.
Barn Owl on a Barn evaluating a Barn Quilt Trail
At 9:41 pm fledgling number two left the hole and fluttered to the roof below. It was now 9:41 pm. With the skies now as dark as they were going to be the camera settled at 0.5 sec. exposures at ISO 12,800.
Almost immediately the hole opening was occupied with two more faces!
Fledglings three and four would remain in the hole peering out as the other Barn Owl fledglings moved to the left edge of the roof and began to scale the main roof toward the peak. At this point our cameras were failing their autofocus so we decided to start packing up.
As we stepped onto the road we could now see the two fledgling Barn Owls on the side of the roof silhouetted against a slightly lighter sky. I decided to try for a quick video when the silence of the evening was interrupted by an ear-splitting "SCREAM" of an adult Barn Owl calling from the trees on the west side of the barn. We couldn't see it but decided that it was time to head back to the car. It was now 9:58 pm!
We could happily report that at least 4 of the Barn Owl hatchlings were still in the box at the beginning of the evening, and that at least two had left the box. They, and at least 1 adult Barn Owl was testament to a successful return of Barn Owls to the Ottawa NWR and NW Ohio.
According to the Cornell Lab of Ornithology (birdsoftheworld.org) Barn Owls (Tyto alba) are perhaps the most widespread owl in the world. Here in the US their distribution is limiting the farther north they are found. "Populations very low in most northern peripheral areas within the mapped range (Figure 1); e.g., number of known breeding pairs per state was <20 (often well below) in Ohio, Indiana, and Illinois during the 1980s, even though specific searches were made for this species (B. Peterjohn, pers. comm.)." - Birds of the World, Cornell
Birds of the World, Cornell Lab of Ornithology
The question of their breeding habits came up, as we were surprised to learn of Barn Owl eggs in the nest box since May? However, according to Cornell, "Eggs laid at 2–3 day intervals; mean interval 2.3 ± 0.2 days, range 1–7, n = 18 (Smith et al. 1974a)", so six eggs is a good clutch and evidence of a good food source in the region.
Onset Of Broodiness And Incubation In Relation To Laying
Incubation by female only; begins with the first egg.
Altricial (naked, eyes closed) and nidicolous (stay in nest). Hatching mass for T. a. pratincola, 12.3-–21.2 g (mean = 16.4 ± 1.5 g, n = 45, Rich and Carr 1999). Hatching mass for T. a. alba and T. a. guttata, 13 and 14 g, respectively (Taylor 1994a); T. a. affinis, 13.5 ± 2.0 g, n = 100 (Wilson et al. 1987) and 18.5 ± 1.1 for T. a. javanica (Lenton 1984b). Young utter faint food call and discomfort twitter, unable to rise; first down (protoptile) sparse grayish white on the upperparts, front of tarsus and toes, pink bare areas on sides of neck, central belly, and back, bill ivory colored (Cramp 1985a).
Growth And Development
Growth pattern similar for five races (alba, pratincola, affinis, javanica, and stertans). See Figure 3. Crawls feebly by 1st day, holds head up strongly by 12th day, walks well by 14th day, can swallow whole mice by 16th day, stretch and flaps wings by 30th day, first flight at about day 55, independent of adults by 76-86th day. Stands upright by 15th day when female is absent but still sleeps lying down until about 45th day; rolls onto back in defense and gradually begins to strike defensively with claws as age increases. See Bunn et al. (Bunn et al. 1982) for detailed discussion. Members of brood sleep huddled together; little strife among nestlings—--some squabbling over food. Older nestlings may feed younger nest mates (Epple 1979, Bunn et al. 1982, Marti 1989). See the Cornell Lab of Ornithology's Nest Box Cams for details.
Fratricide
Little if any evidence. Entire broods dying of starvation in Utah showed no evidence of fratricide (Marti, pers. obs.). Cannibalism occurs frequently (Baudvin 1978, Bühler 1981, Lee 1998) but no evidence that siblings are killed - probably eaten after dying of starvation or exposure.
Brooding
All brooding by the female; begins immediately after hatching and lasts variably until oldest young is about 25 days old. In large broods, youngest nestlings may be only about 11–13 days old when female stops brooding but apparently are kept warm by their nest mates.
Feeding
Male brings food to the nest but only female feeds the young. Initially prey is torn into small pieces and given to the young bill to bill. In first few days young are fed at about hourly intervals throughout 24 h (Bunn et al. 1982). Young able to swallow prey whole by about two weeks, then adults merely deliver prey to the nest and depart. Female begins to hunt at about this time. Young fed same diet as adults (Smith et al. 1974a). Rate of feeding varies with number in brood. Nightly rate highest shortly after activity begins and again before dawn (Marti 1989, Pikula et al. 1984). As many as six prey delivered in 35 minutes (Bunn et al. 1982). One food item is brought per trip. Adults arrive with the prey in one foot, land outside the nest site, transfer the prey to the beak and enter the nest (Marti, pers. obs.). Food apportioned to the nestlings when they are too young to feed themselves; later no attempt made to apportion. See http://www.birds.cornell.edu/birdhouse2/nestboxcam/ for live views of adults feeding young.
Nest Sanitation
Female eats feces until youngest nestling is about ten days old. Older nestlings defecate over edges of nest, nest cavity permitting (Bunn et al. 1982). Nestlings scratch trampled and shredded pellets and other nest debris backward out of cavity entrance—presence of shredded pellets mixed with excreta below a nest site is a good indication that the site was used for nesting (Marti, pers. obs.).
Departure From The Nest
In England, first flight at 50–55 days of age (Bunn et al. 1982). Mean fledging time in Utah, 64.3 d ± 0.5 (SD) (Smith et al. 1974a). Departure from nest is extended; fledglings return to nest cavity to roost for several weeks and may roost in the vicinity of the nest for 7–8 weeks after flying (Smith et al. 1974a, Baudvin 1975, Lenton 1984b, Marti, pers. obs.). Departure from the nest occurs at night.
Association With Parents Or Other Young
Fledglings normally remain dependent upon the adults for 3–5 weeks after flying (Courtney and Debus 2006, König and Weick 2008). Adults roost away from the nest site and interact with the young only to bring food. Siblings commonly roost together for many weeks after first flight.
Ability To Get Around, Feed, And Care For Self
First flights clumsy with awkward landings. Rapidly gain strength and agility in flight and practice prey capture by pouncing on inanimate objects; first successful capture observed in England at 72 days of age (Bunn et al. 1982). Last fed by parents in 12th–13th week (Bunn et al. 1982).
I am most grateful to both Jack and Janet Volker for allowing me to tag along with them on this little adventure. My first Barn Owls in the wild!
Congratulations and thanks also go to Rebecca Lewis and the rest of the Ottawa NWR staff for allowing us to discretely witness the fledging of the Barn Owl chicks. Please, Mom and Dad owls, teach your kids to stay away from the road until they are old enough to find homes for themselves!
Notes regarding image processing: All images were imported into Lightroom Classic, temperature-corrected to remove the blue cast present from shooting in total darkness. Exposure compensation added (as much as +2.50). Highlights reduced, Shadows increased to show dark areas within hole and brighten owl faces, White-Balance increased before applying AI Denoise (50% at ISO 12,800 and below, 75% at ISO 25,600). Exported to Photoshop where Levels adjusted to maximize brightness w/o loss of highlights, Saved as Tiff, downsized to 2048 px and saved as JPG. AI Denoise did an incredible job of eliminating noise and recovering image detail / color as shown in images above.
Epilogue 1: Chiggers! I woke up Wednesday morning "COVERED" in dozens of small red bites around my ankles, backs of my knees, waist and groin area. Inflammation and itchiness was intense. Jack and Janet reported the same; they even went out Wednesday evening and got bitten even more, so there was misery to go around. Benadryl, topical cortisones and anti-histamines were needed for the next 3 days before the inflammation subsided. As of 7/23/23 the inflammation and itchiness is gone, but the red bites and welts remain. As long as I don't start scratching I'm ok to resume field work.
Epilogue 2: Jack and Janet went out Wednesday night and reported the last 2 Barn Owls fledged and left the nest. He was able to get pics and reported no new faces in the hole.
Barn Owl (Tyto alba) 5 1 adult and 4 fledgelings left the box at 9:15 - 9:45 pm. See blog post for photos/details: https://birdingthroughglass.blogspot.com/2024/06/fledging-barn-owls-18-jul-2023.html Gray Catbird (Dumetella carolinensis) 2 Veery (Catharus fuscescens) 1 Wood Thrush (Hylocichla mustelina) 1 Song Sparrow (Melospiza melodia) 2 Common Yellowthroat (Geothlypis trichas) 2
