Rufous vs Gray
From the Peterson Field Guide.
The Eastern Screech Owl is a species that have two distinct morphs and live within the same population (polymorphism). It is generally known that gray-morphed Screech Owls are more frequently found in the North and the rufous-morphed birds are mostly found in the South. Many publications will discuss this relationship with the rufous-morphed birds not being able to handle the colder winters and I know there are some studies are trying to prove that. I did find an interesting publication by Mosher and Henny (1976) who explains how the rufous-morphed Screech Owls oxygen uptake is greater than the gray-morphed birds when exposed to lower temperatures. I have also heard about the relationship with the different morphs and tree species that are found in the areas !! (Note how gray background with the rufous bird makes the owl stick out more!)
Photo by Jim Toner
We regularly find the gray-morphed Eastern Screech Owls here in Allegany State Park and I have only once seen a rufous-morph bird within the area (was dead from a vehicle strike). Although, I am very sure that I am missing many of the rufous birds due to hearing more than I actually get to see. So you can believe how excited I was last week when a coworker showed me a photo of this rufous-morphed bird that he photographed in his front yard! He explained how he flushed the bird from the ground when he came home one evening. Then quickly ran into the house for his camera and found it to be very cooperative in allowing him to capture a few photos. I would like to thank Jim for allowing me to share this with everyone!!
If you are one who watches football . . . . happy Superbowl Sunday to you!!! I am not a big fan . . . so maybe I will go outside and try call some Screech Owls in! The odds are that if I do call a bird in it will be Gray-morphed owl (if anyone is placing bets on birdbowl pools)!
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