Barred owls (Strix varia) are year-round residents across much of the eastern United States and southeastern Canada. These medium-sized owls with distinctive striped plumage and haunting calls are most vocal and easiest to detect during their breeding season from late fall through winter.
When does the Barred Owl breeding season occur?
The breeding season for Barred Owls extends from late fall through winter, typically November through February. During this time, Barred Owls are very vocal as they establish territories, attract mates, and defend nest sites.
Here is a more detailed breakdown of the Barred Owl breeding timeline:
- Late October to November: Increased calling by male Barred Owls to establish territories and attract potential mates.
- December to January: Height of breeding season with frequent duet calls between established pairs.
- February: Nest building and egg laying reaches its peak.
- March to mid-April: Brooding and rearing of young occurs.
So while Barred Owls may call sporadically throughout the year, they are by far the most vocal and responsive from November through February during pairing, courtship, and the early nesting period.
What types of vocalizations are most common during breeding season?
Barred Owls have an extensive vocal repertoire with over 13 distinct vocalizations described. The breeding season brings a marked increase in several signature vocalizations:
- Territorial hooting: Loud, rhythmic series of 5-8 notes (“hoo, hoo, too, HOO, hoo, hoo, too”) given by males to establish territories.
- Duets: Male and female alternating hoots to strengthen pair bond.
- Contact calls: Short, low hoots and gurgling notes used by mates and family groups to stay in touch.
- begging calls: Harsh, rasping notes by females soliciting food from males.
The most recognizable Barred Owl calls – the 8-note hooting sequences – are generally given only by males during territory establishment and defense in fall and winter. Listening for these rhythmic hoots is the most reliable way to detect Barred Owls during breeding season.
Why are Barred Owls so vocal during breeding season?
Barred Owls experience a surge in vocal activity in fall and winter for several important reasons related to breeding:
- Attracting mates: Frequent calling by unmated males helps attract females to potential nesting sites.
- Defending territory: Male hoots ward off rival males from nesting areas.
- Pair bonding: Duetting helps strengthen pair bonds between mates.
- Staying in contact: Family groups keep in touch with contact calls.
In addition, the cold weather and leafless trees in fall and winter allow sound to carry further, making this the ideal season for long-distance vocal communication. The functions of territory defense and mate attraction are especially reliant on vocalizations traveling long distances through the forest.
How does calling frequency change through the breeding season?
Barred Owl vocal activity is dynamic throughout the breeding season, with some distinct trends:
- Male hooting activity peaks in late fall and early winter during territory establishment.
- Duetting between established pairs is most frequent in December and January.
- Short contact calls predominate later in winter as pairs bond and prepare to nest.
- Vocal activity declines after eggs are laid in late winter.
In general, the most vigorous hooting and duetting occurs in the early breeding season from November to January. Later stages like brooding and rearing young require less vocal communication between mates. Tracking seasonal shifts in vocal types can reveal Barred Owl breeding phenology.
How does time of day affect vocal activity?
Barred Owls exhibit definite peaks in daily vocal activity:
- Early morning: Intense calling occurs in the two hours before dawn, especially by males on territory.
- Late afternoon/early evening: Another peak calling period late in the day.
- Throughout the night: Sporadic calling and duetting continues all night long.
- Mid-day: Least vocal period during daylight hours.
Pre-dawn hours are generally the best time to elicit responses when surveying for Barred Owls. Cool temperatures, low wind, and heightened territorial motivation just before dawn create ideal conditions for long-distance hooting. Late afternoon into early evening is another productive calling period.
How does weather affect vocal activity?
Weather conditions have notable effects on Barred Owl calling patterns:
- Cold, calm nights: Ideal conditions that allow calls to carry farthest, resulting in more vocal activity.
- Rainy or stormy weather: Suppresses calling and duetting activity.
- Wind: Impedes the broadcast of calls, reducing vocal activity in windy conditions.
- Following storms: Flush of intense calling often occurs for 1-2 days after storms.
In general, cold temperatures just below freezing with low wind provide the best conditions for detecting Barred Owl voices. Stormy weather inhibits their ability to effectively communicate vocally.
How to optimize chances of hearing Barred Owls
The following tips will maximize your opportunities to detect vocal Barred Owls during breeding season:
- Survey November to February when pairs are establishing territories and most vocal.
- Target cold nights with temperatures below freezing and minimal wind.
- Listen during peak activity periods in pre-dawn hours or early evening.
- Use broadcast of male calls to elicit responses from territorial birds.
- Follow storms when vocal activity surges.
- Focus efforts near forest openings and riparian areas as territory centers.
Any forested areas known to support Barred Owls are worth surveying during the breeding season if you listen during optimal times and conditions. With patience, you’re likely to be rewarded with the haunting hoots of this vocal owl species.
Conclusion
In summary, Barred Owls experience a major surge in vocal activity every fall and winter during their breeding season from November through February. Signature territorial hoots by males, duets between mated pairs, and contact calls within families punctuate the night at this time of year. Cool temperatures, pre-dawn hours, and post-storm conditions provide the best opportunities to detect these vocalizations. Tracking seasonal and daily peaks in Barred Owl calling behavior sheds light on their breeding ecology and improves monitoring and survey efforts. Appreciating the nuances of Barred Owl vocal patterns allows observers to reliably enjoy these birds at their most talkative time of year.