Monday, December 5, 2011

Snowy Owls cast a bewitching spell over most birders.  Here in the Midwest, where the species can be considered rare, the news of a Snowy being sighted tends to draw flocks of birders to the location.  And, that is the case with a Snowy Owl found on December 1, 2011 by Don Broadlick at Indianapolis Regional Airport (formerly Mount Comfort Airport).  Broadlick was visiting the airport in Mount Comfort in Hancock County to look for Short-eared Owls, which are seen in most winters in small numbers at the site.  He was quite surprised to find a Snowy Owl atop one of the buildings at the airport.  The owl was such a shock he was concerned that he was misidentifying the bird.  But, he obtained a photo and contacted me late on December 2.

The following morning, I arrived at the airport shortly after dawn and quickly located the owl atop one of the hangars.  Word of the bird's continued presence went out on IN-BIRD - an email forum where bird sightings for the state are posted - and on Facebook.  Birders started making their way to the airport to view this visitor from the tundra.  Most birders with previous Snowy Owl experience said the bird was a male because of its light barring and because it only had two rows of loose barring on the tail.  The bird was extremely cooperative for most of the day by perching atop a handful of different buildings, allowing people spectacular views.  Frequently, people need to use a scope while standing on a county road to view a Snowy out in the middle of a corn field.  Let me tell you, that is a less than satisfying experience.  This was quite the experience for the 60 or so birders and photographers that saw the bird on December 3.  Even I, the master of terrible photos, obtained a pretty good photo of the bird. 


A natural question is, "Why is this bird here in Indiana?"  Snowy Owls are well-known as an irruptive species meaning that every now and then large numbers fly south of the breeding range to winter.  It is thought by most that the irruption is caused by a population crash of lemmings, which is the primary prey for  the owl.  Lemmings are rodents and are related to mice and rats.  They go through boom and bust population cycles.  When populations are high, Snowy Owls are able to successfully raise larger broods.  When populations crash, Snowys may not even nest at all.  So, it make sense that when lemming populations plummet, Snowy Owls must fly south to find food.

However, it's also true that Snowy Owl irruptions may occur in years with very high lemming populations.  And, in fact, arctic researchers say that lemming populations were very high in 2011.  So, if there were so many lemmings available, why are so many birds flying south?  Well, with lemmings to gorge on in 2011, Snowy Owls had a productive breeding season.  The large number of young owls probably reduced the overall lemming population and created territorial disputes with adult birds.

Snowy Owls tend to be solitary birds with large territories.  Parents and other adults drive younger birds away from productive hunting grounds on the tundra.  The younger birds don't have much of a choice other than to fly south.  Most of the Snowy Owls that appear in the Midwest are indeed young birds.  The bird being seen at the Indianapolis Regional Airport appears to be either a hatch-year or second-year male.

If you get the chance, visit the airport to see this special visitor.  It is quite the experience.  Take the family.  Take the neighbors.  It will be a memory that you will treasure the rest of your life.