I realize the first week of March is probably just the “Spring of Deception” and certainly no better than “Fool’s Spring,” but I still enjoyed the recent, however fleeting, turn in the weather.
The first days warm enough for sandals-with-socks are always cause for celebration.
With spring, whatever its deceit, come flocks of waterfowl migrating north over the continent. Some will find suitable breeding grounds in the Northern Plains or Rocky Mountains, but for others, their ambitions lie beyond the Arctic Circle.
Destinations in the far north are more likely the case for these Fool’s Spring birds. Early migrators are intent on the tundra’s best nesting sites.
The immense flocks seem like a smoke plume rising above a prairie fire, though there was a time for baby boomers like me when waterfowl seemed doomed. It was rare to see Canada geese when I was young, but years of conservation work paid off. Recently, in downtown Denver, I had to shoo away a gaggle of “wild” Canada geese that had been grazing a patch of grass in a filling station parking lot.
On the plains east of the Rocky Mountain Front, the cousins of those urban dwelling birds are gathering for the trip north.
The most dramatic are snow geese, the species most likely to be mistaken for atmospheric phenomena. When a cloud of snow geese rises up off the prairie it doesn’t require a degree in biology to understand their recovery is so complete the birds are now overgrazing their summer range.
There’s now a spring hunting season for snow geese. It’s basically a market hunting revival: unplugged shotguns, electronic calls and no bag limits are the norm. You just can’t bring your snow geese to town to sell to restaurateurs as did the market hunters of the 19th century. Overkill is now for conservation, not commerce.
I was out walking the dogs the other day when we were overtaken by a mass of migrating snows so vast it was nearly 10 minutes before they passed. The birds flew in the familiar V pattern, and there were so many formations they appeared like the overlapping scales of a fish.
These are ambitious birds, heading for nesting grounds in the Canadian Arctic, Alaska and even Siberia.
The V is an energy conservation strategy — like the drafting you see in NASCAR, only without the fiery wrecks and 20-car pileups. Folks always figured there was a reason for the formation, but it took miniature electronics to confirm the birds at the end didn’t have to work as hard as the birds at the point.
The birds in front are doing more than just creating a slipstream, like those soon-to-be-smashed race cars. With each wingbeat, one migrating bird creates a pillow of updraft, and the trailing bird, by placing its wingtip in just the right spot — behind and slightly above — gets to ride that updraft all the way to Siberia.
At first the folks who study avian flight mechanics concluded that the precision needed to place that wingtip perfectly atop that pillow was too great for geese. Further study proved the birds knew exactly what they were doing.
Which shouldn’t come as a surprise. Migrating birds are living, breathing flying machines. Putting their wingtips just where they need to be, at the beat of the formation’s silent metronome, likely comes as easy to geese as drinking beer until one falls from their bar stool comes to some of my close acquaintances.
This technique is learned. A researcher using an ultralight to teach orphaned ibises their ancestral migration flight path was surprised the birds didn’t V-up behind the ultralight, at least not at first. By the time they arrived, however, the ibises had arranged themselves in a tidy V.
It’s spring, man! Birds have places to be.
Rob Breeding writes and blogs at www.mthookandbullet.com.