Saturday, January 29, 2022

Snowy Owls

Environmental & Science Education, STEM, Behavior, Biodiversity, Nature, Wildlife

Ed Hessler

It is the time of the northern year that snowy owls are sometimes reported far south of their northern environment across the U.S. It used to be thought that these deep incursions south were caused by food shortages. Lemmings are a meal of choice although they eat a variety of prey., e.g., sea birds.

It turned out that this idea was backward for snowies; it is often true for other species (see irruptions link below, a behavior that is complex in a variety of birds).  For Snowy Owls, a good food year or two results in the production of many young. The younger birds must find their own space in which to live and this is when we see them in places that surprise as well as enchant us us. Scouting, exploring. Always looking for good places to feed. These birds are also great nomads and accumulate many kilometers during their lives.

Val Cunningham who writes about birds for the Minneapolis Star Tribune (January 19, 2022) took the occasion of a report of three "snowies" seen at the Minneapolis -St.Paul Airport (MSP) to write about these birds. (The article is behind a subscription wall. This newspaper has talented, knowledgeable, and gifted writers on birds. On Wednesdays the first section I read is the one that includes their reporting.) It is a lovely story and he rehearses the food hypothesis and evidence.
Cunningham notes that snowy owls are tall, measuring "about 24 inches (~61 cm) from their heavily feathered feet to the tops of their big round heads," which is mostly a feather ball. He reports on the program started at Logan International Airport, Boston, now 40 years old, capturing and relocating snowy owls at Logan. Norman Smith who started this work said "'In an average winter, I relocate 15 to 20 owls but the big year, 2013, I relocated 121 owls.'" Cunningham continues, They are released "either to coastal salt marshes or to areas north of the airport, both good hunting grounds." 
The Cunningham report includes three magnificent black-snd-white photos--what else this time of year, a black and white world at ground level.

Cunningham's story led me to the Cornell Laboratory of Ornithology for two maps. The first is the range map for snowy owls. The other is a sightings map from 2017 - 2022. In addition, is this video (3m 38s) on snowy owl invasions (known as population irruptions).
A few years ago on a cold winter night while walking home, I "felt" something directly overhead while taking a short-cut through a parking lot. I looked up and then stopped to look around. There perched atop an old wooden electricity pole was perched a snowy owl, the first one I'd ever seen. And I was alone with it, at night. I was delighted that this was a chance encounter, the bird's choice to fly so close and then to perch not far away to survey the landscape before launching and then flying, stealth-mode to the SE.

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