Wednesday, April 26, 2017

My family first moved to Exeter in 2002.  Our first home was right on the edge of the Swasey-Henderson Town Forest with direct access just outside our door.  We jumped at the opportunity to explore the forest as often as possible.  It was a playground for instilling a sense of discovery and adventure into our then elementary-aged daughter.  Our efforts were well rewarded with sightings of beaver, birds, fisher cats and all sorts of rodents.  One memorable highlight was wing-patterns in the snow, ending in a divot covered in bits of fur.  This was evidence, we think, of an owl’s successful hunt the night before.  
My friends John and Andrea were both born and raised in Exeter.  They’ve deepened their roots by raising their own family here.  For the past decade Sean and I have walked the Swasey-Henderson Town Forest hundreds of times with John and Andrea and many other friends.  We occasionally spy a Barred Owl on these walks, with more regular sightings in 2016.  There is no saying for sure it’s the same individual we see or if there is more than one but the owl makes itself surprisingly visible at times.  There has also been a Great Horned Owl in the vicinity, possibly more than one.
There are approximately twenty species of owls breeding in North America.  Of these, there have been twelve recorded in New England.  So far, I have seen or heard three species in and around Exeter.  With over 2300 acres of open space around town there is plenty of habitat types to support a few more owl species.  If you zoom out beyond Exeter’s boundaries, there are far more forested, field and wetland habitats that many avian species, including owls, can easily access.
Barred Owls are territorial and non-migratory.  Their territory can be anywhere from 200-900 acres!  That is 0.75-1.5 square miles they will defend especially aggressively during nesting season, which is wraps up pretty soon.  They are monogamous, forming permanent pair bonds.  Courting begins in winter, usually February but can be earlier, near the nest site using much of the same awkward-looking techniques that us humans will use.  There is hooting, screeching, chasing, swaying, sidling and raising-of-wings involved.  An established pair will engage in mutual feeding and preening, too.  Sound familiar?  Maybe our Barred Owl is raising a few chicks this season, although I have not seen sign of it since last November.
A known predator of the Barred Owl is the Great Horned Owl.  This might explain why both species have been seen in the same woods.  The Great Horned Owl requires anywhere from 0.1 – 1 square mile of territory, the actual size depending on nesting density and food supply.  Hmm, let’s think about this.  The smaller Barred Owl requires a larger territory than his bigger cousin, the Great Horned Owl?  That seems kind of backwards.  I certainly have more to learn about this territory stuff.
While the Barred Owl’s preferred habitat is deep, swampy mixed-woods forests near waterways, the Great Horned Owl is opportunistic in habitat choices.  It has been as successful in a New England forest as it has been in the desert.
I remember the first time I ever saw an owl in flight.  It was magical!  At dusk over an open field on Plum Island in Massachusetts a Great Horned Owl glided against a backdrop of grayish-pink sky and silhouetted trees.  I knew immediately it was an owl and not any other large bird of prey because of the flat face.  You can’t miss that identifying feature.  The size of the bird and the surrounding habitat gave away its identity.  The glide was beautiful.  Low to the ground, nearly at eye level, it was most likely hunting.  So effortless yet very purposeful.  An owl’s wings are designed for silent flight.  The broad shape provides a large surface area that allows them to float rather than flap.  The leading edges of the primary feathers have a combed or serrated surface that shifts the flow of air, lowering the decibel level to near silence.  Amazing evolutionary advantage!
Great Horned and Barred owls share a similar diet: anything from small rodents and insects to amphibians and reptiles.  Both will take down small birds but the larger Great Horned Owl is known to take down animals larger than itself, such as Red-tailed hawks and young foxes.  It has even been known to wade into water for a meal!  Of course, as was already mentioned, the Great Horned will readily make a meal of the Barred Owl, too.  Definitely an opportunistic feeder.
A third species, the Screech Owl, is also part of the Exeter community.  I live within a mile of downtown and on two occasions (but as many as six years apart), a Screech Owl perched itself in a fir tree across the street from my house and whinnied the evening away.  Among the smallest of owl species, I was not able to see it on either occasion, unfortunately, but its unmistakable call was clear.  Soft, distinctive and even a little eerie, it can be quite unsettling if you don’t know the source from where it comes.  I heard it again just two nights ago in the middle of the night!
One clue to finding an owl is a behavior called "mobbing".  When a predatory bird is in the area prey birds will become agitated and collectively harass the predator as a means of driving it away.  This behavior is quite loud and very visible.  The mobbing might take place in flight, but sometimes the predator will try to outlast his agitators by staying put on a branch.  Either way, the agitated prey birds will easily lead your eyes to the predator.  Any prey bird will use this tactic to protect their eggs or chicks but, typically, crows will mob hawks and owls; in turn, Blue jays and smaller birds will mob crows, as crows are notorious egg and chick stealers.  Surprisingly, even the smallest of birds will go after a large bird of prey to protect its young.
Next time you head out for a walk in the woods or a walk around your neighborhood, pay attention to the sounds.  Look up and scan the tree-tops now and again.  Slow to a crawl, stand and listen….turn around in the spot where you stand.  You just might see a pair of large, round eyes staring right back at you!
If you have had any owl sightings near your home I would love to hear about it.  Please feel free to leave a comment below.

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