The northern saw-whet owl (Aegolius acadicus) is a small owl found in North America. It gets its name from the distinctive call it makes, which resembles the sound of whetting or sharpening a saw. The northern saw-whet’s call is a series of short, whistling toots that rise and fall in pitch and frequency. This call has been described as sounding like “toot, toot, toot, toot” or “poop, poop, poop.” While the saw-whet’s call may not be as iconic as the hooting of a great horned owl or the screeches of a barn owl, it is still a unique and fascinating vocalization. In this article, we will explore the characteristics of the northern saw-whet owl’s vocalizations and the contexts in which they vocalize. We will also discuss how their calls can be used for identification, research, and conservation.
Description of the Saw-Whet Call
As mentioned, the northern saw-whet owl’s advertising call consists of a short series of whistling notes that rise and fall in pitch. The call lasts for about 2-3 seconds and typically includes 6-7 individual notes. The notes have been described as sounding like “poop” or “toot” and occur at a rate of around 2 notes per second. The first few notes tend to be higher pitched and then the pitch falls on the last couple of notes. There can be some variation in the speed, pitch, and number of notes between individual owls. The calls are often repeated every few seconds, sounding like “toot, toot, toot, toot” over and over again.
In some cases, the saw-whet may omit the last couple of lower pitched notes and just give the first few higher “toots.” They also sometimes add an extra note or two to the end of the call. The pitch of the call is often compared to the sound of a bouncing ping pong ball slowly coming to rest. Overall the vocalization has a repetitive, whistling quality unlike the hoots and screeches of many other owl species.
Comparison to the Calls of Similar Species
The northern saw-whet’s call could potentially be confused with the calls of other small owl species. However, there are some key differences that can help distinguish it:
– Boreal owl: Has a similar tooting call but it is faster paced, more hurried sounding, and more variable in pitch.
– Eastern screech owl: Call is a whinny, trembling trill rather than a whistling toot.
– Northern pygmy owl: Makes a low, hollow double hoot (hoo-hoot) rather than a whistled toot.
– Elf owl: Call is a rapid series of single note whistles rather than a call made up of multiple notes.
Once you are familiar with the northern saw-whet’s distinctive tooting vocalization, it can be easily picked out from other species. Listening to audio recordings and learning the calls is the best way to identify the species by ear.
Contexts and Meanings of Vocalizations
Northern saw-whet owls have a few different calls that they use in specific contexts:
Advertising Call
The advertising call described above is by far the most common vocalization given by northern saw-whets. As the name suggests, they use this call to advertise their presence on a territory and attract potential mates during the breeding season. The call carries well and can be heard up to a half mile away on still nights. Males begin hooting on their breeding territories in late winter and continue through spring. The repeated advertising calls are given most frequently just before dawn, when males are trying to attract females to potential nest sites. However, they may call sporadically throughout the night as well.
Calls Between Mates
In addition to the advertising call, northern saw-whets also have some softer vocalizations that are used for communicating with their mate or young. One is a shorter, harsher “chuck” note. They may also make soft whistles or warbles when interacting with their mate or offspring at the nest. These calls are not carried over long distances.
Alarm Calls
When alarmed or agitated, saw-whet owls produce a rapid series of loud, harsh notes described as “keah, keah, keah.” They often make this call when defending the nest from potential predators. The alarm call serves to startle and drive away potential threats.
Fledgling Begging Calls
Young northern saw-whet owls (known as fledglings) produce loud, raspy begging calls when waiting for the parents to return with food. These sounds are similar to the hissing noises made by young screech owls. The noisy begging calls help guide the parents back to the fledglings when delivering prey items.
Non-vocal Sounds
In addition to vocalizations, northern saw-whet owls also produce some non-vocal sounds through actions like clapping their bills or fluttering their wings. These mechanical sounds can also communicate different behaviors or reactions during interactions with mates or predators. Understanding both the vocal and non-vocal auditory signals is an important part of interpreting saw-whet behaviors.
Use of Calls for Identification and Research
The distinctive tooting call of the northern saw-whet owl makes it possible for ornithologists and bird enthusiasts to identify and detect this secretive species. Since saw-whets are small and strictly nocturnal, they can be very difficult to spot visually. However, their vocalizations allow observers to confirm their presence even without seeing the birds. This has enabled a greater understanding of the saw-whet’s distribution, habitat use, and behavior through auditory surveys.
There are a few different ways that the northern saw-whet’s calls have been utilized for research and monitoring purposes:
Broadcasting Recordings to Elicit Responses
One survey technique involves playing recordings of northern saw-whet calls to elicit responses from any individuals that may be present in the area. The saw-whets are likely to call back in response, betraying their presence. This technique, known as playback or call broadcasting, can detect owls that otherwise may have remained silent. Comparing the responses at different locations and times of night also provides insights into habitat use and activity patterns.
Banding and Tracking Studies
Banding studies aim to capture, mark, and release saw-whet owls in order to track their movements and survival over time. Again, drawing the owls in with playback calls is an effective technique for attracting and capturing individuals for banding. The unique ID numbers on the bands then allow the movements of specific owls to be traced if they are encountered again.
Acoustic Monitoring
Remote monitoring devices equipped with microphones can also be deployed to record the vocalizations of saw-whets over an extended period. The audio recordings from these automated detectors can indicate how frequently the owls are vocalizing in a certain area over time. Changes in calling levels may reflect shifts in breeding activity and habitat use. Comparing detections at different locations helps clarify patterns of habitat preference and range distributions.
Assessing Abundance and Population Trends
Careful surveying of saw-whet owls using the techniques above provides valuable data on owl numbers, breeding status, and trends over time in different regions. Repeated standardized surveys can detect population increases or declines. The availability of good baseline population data is vital for effective conservation planning and management. Analyzing call characteristics can also provide information on the age, sex, and health of individuals.
In summary, the recognizable vocalizations of the northern saw-whet have become an invaluable research tool for scientists studying these nocturnal raptors. The owl’s dependable responses to call-playback have facilitated many studies that would not otherwise have been possible for such a difficult to observe species. Continued acoustic surveying and monitoring will be important for detecting any population changes and maintaining protections for saw-whets into the future.
How to Attract Saw-Whets by Broadcasting Recordings
For those interested in observing northern saw-whet owls in the wild, broadcasting recordings of saw-whet calls can be an effective method to attract them and elicit vocal responses. Here are some tips for using call-playback to detect northern saw-whets:
– Use a speaker with good sound quality and volume control. Speaker placement is also important for projecting sound effectively.
– Know the standard calling times – Saw-whets are most vocally active in the couple hours before dawn. Wait for still, non-windy conditions.
– Begin with a one minute recording of the advertising call played on repeat. Listen silently for several minutes for any response calls.
– Increase volume gradually if needed to project the sound further. Take care not to overamplify.
– If there’s no response after 15 minutes, try moving to a new suitable habitat area and repeating the playback.
– Pay attention to the direction and pattern of any responses to pinpoint the owl’s location. Move towards responsive individuals.
– Using a light can sometimes help spot the owl if you determine its general location by ear. But minimize disturbance of the owl and avoid overuse of lights.
– Never approach or harass roosting owls once located – observe them from a respectful distance.
– Carefully document any observations to contribute to knowledge of distribution and abundance.
With persistence, practicing call-playback in appropriate saw-whet habitat can result in thrilling experiences observing these vocal nocturnal raptors up-close in the wild. But follow ethical birding and research guidelines to ensure the welfare of the owls. Proper use of call recordings provides a unique window into their fascinating behavior and ecology.
Conclusion
The northern saw-whet owl’s repetitious, whistling toot call is a distinctive sound of the nights in the forests of North America. Their intriguing voices reveal a hidden world of mysterious nocturnal rituals. Learning the nuanced meanings of the saw-whet’s vocalizations provides insights into their cryptic behaviors and survival strategies. As research continues to unveil their elaborate modes of acoustic communication, our appreciation for the northern saw-whet deepens along with our commitment to conserving these captivating creatures. Whenever we hear the mesmerizing toots of this petite owl in the darkness, we are reminded of nature’s wondrous creativity. With careful listening and respectful study, we can ensure that the saw-whet’s alluring song remains part of our woodland’s night music for generations to come.
