Remember That Day in ’91?
Sometime in the next 10 days, there will be a migration event.
I grew up anticipating migrations—and not just because I’m a waterfowl hunter. Fall and early winter feature spectacular migrations. They begin with shorebirds in late July. Pelicans, monarchs, broad-winged hawks and blue-winged teal migrate from August through September, while gadwalls, canvasbacks and geese begin to head south in October. By November, mallards, scaup and green-winged teal are arriving in Missouri. The season ends when bald eagles, goldeneyes and common mergansers migrate into Missouri in December. Just wait ’til March; it starts all over again … in reverse order.
Seasonal clockwork—driven in the long run by day length and in the near term by weather and habitat conditions—yields the annual certainty of migrations. Our own seasonal clock must operate in the same way. A certain restlessness and awareness that seem to be missing much of the year take hold with the cooler days and high skies of fall.
The annual predictability of migration has been punctuated by benchmarks that have become for me, and others I’m sure, natural reference points. Many conversations this time of year begin with, “Remember that day in November 19__?”
Those who witnessed them will recall the dramatic migrations associated with the Armistice Day storm of November 11, 1940, and the mass migration that occurred during the first 3 days of November 1955. The “grand passages” of waterfowl during these early events were surprises, as was the severe weather that accompanied these movements.
With today’s technology, such as Doppler radar and Internet weather reports, armchair meteorologists can come closer to predicting weather and migration events. Check out falling temperatures in Bismark, North Dakota, and closely-spaced isobars on the weather map. But the technology itself can be affected by migration, as evidenced by the mass movements of snow geese and other migrating birds during early November 1995 that disrupted aviation radar in Kansas City, Omaha and Des Moines.
I’ve kept hunting journals since 1965. A look back through them reveals how much weather and migration go hand-in-hand. The “Halloween Storm” of 1991 preceded a week of near zero temperatures in Missouri. The Midwest “hurricane” of 1998, was defined by record low barometric pressures and 70 mph winds. The most dramatic blue-winged teal migration I ever saw was during a day-long thunderstorm that dumped 5 inches of rain on September 19, 1983.
Professionally, the why and how of migration always have been fascinating to me. There is considerable science to explain the events; yet, quite a bit of uncertainty still surrounds the complexities of navigation and impetus for migration. As compelling as the science is, the spectacle of migration continues to be a personal attraction for me.
Sometime in the next 10 days, take the opportunity to stop and reflect on the natural events that serve as reminders of our own seasonal calendar. In the next 10 days, take note of the mare’s tail cirrus clouds aloft, an approaching cloud bank in the west, a night of falling temperatures and rain, the cold, bright blue days that follow, and the pencil-thin lines of migrating flocks responding to the weather.
I do remember that day in ’91; it was unbelievable!
Dale D. Humburg, Resource Science Division Administrator