LOOK Closely. How many owls do you see?
It's been an incredible roost-watching season and this cam is one of our favorites; after all, 32-years ago Denver’s study of Long-eared Owls began with the research question “are communal roosts comprised of family groups, other related individuals, or non-related individuals?” This cam is the perfect compliment to our on-going research and provides unprecedented views of this unique roosting behavior.
Long-eared Owls are one of the few owl species in the world who roost communally. Clustering in groups of 2 to 20 individuals, these roosts occur during the non-breeding season - the fall and winter. Communal roosts of up to 100 individuals have been reported, although we have never seen numbers like this in our study areas. Last year’s cam filmed as many as 13 birds in this roost. We have learned that these groups are made-up of different sexes and ages, although rarely comprise members of the same family.
So why do Long-eared Owls form these communal roosts? There are several potential reasons. One, grouping together may have thermal advantages during the frigid winter months. Two, it may be a defense against predators – the more eyes on the lookout, the better. And, three, it seems to have social implications for mating: birds from winter roosts turn into the local breeding population. Long-eared Owls are seasonally monogamous but life-long polygamous.
The individuals in this roost may be birds who will overwinter in their local breeding area; birds who have migrated from other areas (presumably more northern climates); or birds who are just stopping over for a bit before moving on. Other individuals - those who may have spent the breeding season here - have migrated to other areas. Birds often continue to move around throughout the winter, both within and outside of the study area, depending on food availability and local conditions.
Overall we know very littl