Sunday, July 10, 2011

The Barred Owl - Spotted Owl cousin and competitor

Although my first great wildlife job was with the lovely, peaceful Spotted Owl (see last post), I also have quite a fondness for the Barred Owl (Strix varia), and why not, they are both interesting and beautiful large owls. I'm sure you will agree as you look at these pictures (this one taken by owl researcher and friend Jamie Acker who lives in Washington)

But here is the thing with the Barred Owl. They have expanded their range from east of the Rockies to the mountain ranges where the Spotted Owl lives - the Cascades and Sierra Nevada.
Being a habitat generalist (as opposed to a specialist like the Spotted Owl), and having much greater prey variety, they have bull-dozed their way through Spotted Owl habitat, first breeding with them (the offspring are called SPARRED Owls), and then displacing them.

When I lived on Bainbridge Island, WA, I met Jamie who was monitoring all the owl species on the island. I introduced color-banding and radio telemetry to his Barred Owl monitoring, and from that we became to know individuals, their habitat preferences and habits, and their offspring's dispersal. Their populations on the island continue to increase and they are very fecund, each pair having 2-3 young per year. This picture of a juvenile Barred Owl was taken this year by owl researcher Dale Herter, who I worked with in WA, conducting Spotted Owl surveys. We had only a handful of Barred Owl detections then, from 2000-2004.

In the Northwest, the Barred Owl populations have increased so greatly that in some forests- they will be managed for (killed) to help the federally threatened Northern Spotted Owl populations recover. I don't think this is a sustainable plan, because Barred Owls are savvy generalists, sort of like crows and coyotes, they are tough survivalists. But the other components of the plan (USFWS 2011) are more sustainable, and include better protection and restoration of Spotted Owl habitat (mature and old growth forests) and introducing fuel reduction and fire management, which opens the understory (important for Spotted Owl prey and hunting).


As with the Spotted Owl, Barred Owl's are quite personable. This is a pair of wild Barred Owls that Jamie is currently observing in his backyard on the island. The female, the larger owl is on the left and the male is on the right. In this picture they have molted all of their tail feathers so they look smaller than they really are. Their tail feathers will grow back in the course of 3 weeks to 1 month. Jamie and I published a paper, exciting for us, about Barred Owl rectrices characteristics and molt.

Jamie has also found that the Barred Owl preys on Western Screech Owls and is likely responsible for their demise on the island. Despite their competitive and invasive nature, it is hard not to have a fondness for the Barred Owls, once you get to them. Go here To see Barred Owls in action!

3 comments:

  1. Hard not to love these beautiful owls, in spite of their out-competing the spotties.

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  2. The barred owls are pressured to invade spotteds’ areas because of habitat loss. Why not address habitat loss and enlarge your forests? Why you have to kill the barred in order to protect spotted? I don’t understand why you Americans are so insane.

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  3. Beautiful Site, Dawn.
    What are "Barred Owl rectricies"
    Mike Ashlock

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