This past Saturday a few of my fellow Audubon Master Birder classmates and I took a trip to find the Short-eared Owl (Asio flammeus) that’s been reported around Denver International Airport (DIA). Success! But wait, was that really a Short-eared Owl? eBird seems to think it was a Long-eared Owl (Asio otus). Why the confusion?
Both Long and Short-eared Owls are medium-sized owls present throughout North America, including Colorado, particularly in the winter. They also share similar habitats, tending to forage in open grasslands for birds and rodents.
At rest, it’s fairly easy to tell the two species apart due primarily to the Long-eared Owl’s prominent ear tufts (feathers), but we only saw the owl flying and, in flight, those ear tufts tend to flatten back against the bird’s head. So what other clues can we use?
In general, the Long-eared Owl is more orangey than the Short-eared Owl, which tends to be paler. The Long-eared also tends to have more extensive barring on the underparts, whereas the Short-eared tends to have more diffuse streaking confined mainly to the breast. While both have heavily marked backs and upperwings, the Short-eared Owl’s wings are also more contrasty than the Long-eared Owl’s. The dark bars on the Short-eared Owl’s tail are also broader and more apparent than the ones on the tail of the Long-eared Owl.
So what do you think? Did we roust a Short-eared Owl? Or was it a Long-eared Owl instead?