Atlas Guide to Owling

Spring is here, and love is in the air for owls! These wonderful and elusive birds can be detected near sundown and early mornings when they are frequently calling, tending to their owlets, or performing courtship rituals such as duets, head bobbing, or feeding one another.  The Great Horned Owl, Eastern Screech Owl, and Barred Owl are a few species that can be found breeding in forests and wooded neighborhoods all throughout North Carolina. These owls will select previously used nests made from a variety of other animals in either hollowed cavities, nest boxes, or tree branches. Owls generally become most active right after sunset and once again seven to nine hours after sunset.

One of the NC Bird Atlas’ goals is for every priority block to have at least two nocturnal surveys completed on eBird and submitted through the NCBA portal in both the breeding and winter seasons.  But before you grab your headlamps, let’s review some guidelines for nocturnal surveying for the atlas. 

1. Safety For Volunteers: 
   • Always use your hazard lights when your vehicle is stopped and never stop in a blind section of the road where traffic cannot see you well in advance, most notably curves and hills.
   • Wear reflective and/or high-visibility clothing and avoid dark clothing.
   • Let someone know where you are going and when you will be returning, and, if possible, travel with a partner.
2. Safety For Owls: 
   • All owl species are sensitive to disturbance, be respectful of their habitats and watchful for signs of distress. Never harass an owl by getting too close, chasing it, or baiting it with prey.
   • Locations must be exact and ideally unhidden on eBird checklists for the purposes of the Atlas, but if concerned, consider temporarily hiding the checklist until the owlets have fledged the nest to reduce potential disturbance.
3. When Should I Go?
   • Surveys for owls are best done on clear nights without any strong winds. Calls are the most reliable way to identify an owl, and strong winds not only reduce owl activity, but also diminishes the surveyor’s ability to hear them.
   • eBird classifies a nocturnal checklist if it begins twenty minutes after sunset till forty minutes before sunrise.
4. Commonly Used Breeding Codes for Owls
   • An owl calling can be coded as (S) Singing Bird,
   • A duetting pair can be coded as (C) Courtship, Display, or Copulation, and
   • A nest full of owlets can be coded as (NY) Nest with Young.
5. No owls? No Problem!
   • Always submit a nocturnal checklist to eBird even if no species were detected.  This effort provides valuable information about detectability, and we can still learn a lot from the absence of owls in certain habitats or times of the year.

Surveying with call playback 

The Atlas encourages use of call playback when nocturnal surveying for owls. Owls are territorial and if they hear a potential intruding owl call they often will call back in response or even fly in close to investigate. Call playback can be done by playing audio of an owl’s call through any device with a small to medium sized speaker. When utilizing call playback to detect owls, always play calls in the sequence of smallest species to largest species with five-minute intervals between species. For example, play eastern screech owl, then barred owl, then Great Horned Owl. Since larger owls will prey on smaller owls, this method increases detection rates of smaller owls. If a smaller owl responds, move to another location to avoid attracting larger owls. 

Finally, remember that playback can be disruptive to a bird’s behavior. Avoid prolonged bouts—no more than two minutes of playback per species at each stop. Once an owl has been detected, stop the recording as soon as possible. Avoid attracting owls to hazardous areas such as busy roads. Always use your best judgment when it comes to the use of playback for nocturnal surveys.

Barn Owls, while not considered “true owls” because they belong to a different taxonomic family, are nevertheless keen nocturnal hunters and can be found throughout North Carolina, nesting in tree hollows, cliff ledges, caves, and all sorts of abandoned or infrequently visited human structures. These owls are mostly silent and not as responsive to audio playback. But you can wait around coastal marshes, or other extensive grassy areas around dusk in hopes of seeing them flying around. 

If you find yourself in the mountains you may be lucky enough to encounter a Northern Saw-whet Owl. These mysterious, cute little owls breed in high-elevation spruce-fir stands found in Appalachian areas such as the Blue Ridge Parkway and Great Smoky Mountains National Park. Northern Saw-whet Owls’ wintering range could possibly encompass more than the Appalachian region, but too little is known about their ecology to be certain of it due to how cryptic and under-studied the species is.

Don’t be fooled! Eastern Screech Owls exhibit polymorphism, having both a red morph and gray morph. Both morphs can occur throughout North Carolina and interbreed with one another. However, the red morph is the most common type to occur here and the southeastern US overall.  

Have these fuzzy feathered owlets moved into your neighborhood or local park? Barred Owls are arguably the most commonly encountered species of owl in our state. This is partly due to their ability to nest in urbanized landscapes, only requiring habitats with some mature trees. Interestingly, they were originally thought to be a mature forest obligate species.

Last but certainly not least, the Great Horned Owl is our state’s largest species of owl (the distinction of heaviest owl in North America belongs to the Snowy Owl, which is also tied for longest wingspan with the Great Grey Owl). Be sure to read the NC Bird Atlas’ species profile for these formidable hunters here. 

— Dan Watson is a skilled NC Bird Atlas technician working in the Piedmont of North Carolina.

Sources: 

Beckett, Sean R. , and Glenn A. Proudfoot. 2011. Large-Scale Movement and Migration of Northern Saw-Whet Owls in Eastern North America. The Wilson Journal of Ornithology 123(3): 521-535.

Clément, Marion & Kyle Barrett, and Robert Baldwin. 2019. Key habitat features facilitate the presence of Barred Owls in developed landscapes. Avian Conservation and Ecology 14(2):12.
https://doi.org/10.5751/ACE-01427-140212

Clément, Marion, Julia Shonfield, Erin M. Bayne, Robert Baldwin, and Kyle Barrett. 2021. Quantifying Vocal Activity and Detection Probability to Inform Survey Methods for Barred Owls (Strix varia). Journal of Raptor Research 55 (1): 45–55.  https://doi.org/10.3356/0892-1016-55.1.45

Cornell Lab of Ornithology. 2019. All About Birds. Cornell Lab of Ornithology, Ithaca, New York. https://www.allaboutbirds.org

NC Bird Atlas Volunteer Handbook 2021-2026: https://ebird.org/atlasnc/about/handbook

Project Owlnet: https://www.projectowlnet.org/